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SEN01968-02 HYDRAULIC EXCAVATOR PC138US PC138USLC PC138US- 20001 SERIAL NUMBERS and up PC138USLC- 20001...
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SEN01977-02 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 00 Index and foreword Index Composition of shop manual .......................... 2 Table of contents ............................. 4 PC138US, USLC-8...
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SEN01977-02 00 Index and foreword Composition of shop manual The contents of this shop manual are shown together with Form No. in a list. Note 1: Always keep the latest version of this manual in accordance with this list and utilize accordingly. The marks shown to the right of Form No.
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00 Index and foreword SEN01977-02 Troubleshooting of hydraulic and mechanical system (H-mode) SEN02468-01 Troubleshooting of engine (S-mode) SEN02469-01 50 Disassembly and assembly SEN01975-00 General information on disassembly and assembly SEN02709-00 Engine and cooling system SEN02710-00 Power train SEN02711-00 Undercarriage and frame SEN02712-00 Hydraulic system SEN02713-00...
SEN01977-02 00 Index and foreword Table of contents 00 Index and foreword Index SEN01977-02 Composition of shop manual....................... Table of contents ......................... Foreword and general information SEN01978-01 Safety notice..........................How to read the shop manual ..................... Explanation of terms for maintenance standard................Handling of electric equipment and hydraulic component............
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00 Index and foreword SEN01977-02 Swing motor ..........................19 Travel motor ..........................27 Center swivel joint ........................36 Solenoid valve..........................40 PPC accumulator ........................44 Holding valve..........................46 Multi-control valve ........................51 Work equipment SEN02551-00 Work equipment .......................... Dimensions of components ......................Hydraulic cylinder........................
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SEN01977-02 00 Index and foreword Checking cab tipping stopper ...................... 52 Adjusting mirrors ......................... 52 Testing and adjusting, Part 2 SEN02459-00 Special functions of machine monitor..................Testing and adjusting, Part 3 SEN02460-01 Handling voltage circuit of engine controller................Preparation work for troubleshooting of electrical system............Procedure for testing diodes .......................
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00 Index and foreword SEN01977-02 Failure code [CA352] Sensor sup. 1 volt. low error..............Failure code [CA386] Sensor sup. 1 volt. high error ..............Failure code [CA435] Abnormality in engine oil pressure switch ..........10 Failure code [CA441] Battery voltage low error ................Failure code [CA442] Battery voltage high error .................
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SEN01977-02 00 Index and foreword Failure code [DY2DKB] Wiper drive (for) short ................16 Failure code [DY2EKB] Wiper drive (rev) short................18 Troubleshooting of electrical system (E-mode) SEN02467-00 Before carrying out troubleshooting of electrical system............. Information in troubleshooting table .................... E-1 When starting switch turned ON, machine monitor displays nothing........
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00 Index and foreword SEN01977-02 H-24 When upper structure stops swinging, it makes large sound ..........24 H-25 Hydraulic drift of swing is large................... 25 H-26 Flow rate in attachment circuit cannot be adjusted ............26 Troubleshooting of engine (S-mode) SEN02469-01 Method of using troubleshooting chart ..................
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SEN01977-02 00 Index and foreword Removal and installation of hydraulic tank assembly ..............Removal and installation of hydraulic pump assembly..............Removal and installation of control valve assembly..............12 Disassembly and assembly of control valve assembly ............... 17 Disassembly and assembly of work equipment PPC valve assembly ........27 Disassembly and assembly of travel PPC valve assembly ............
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00 Index and foreword SEN01977-02 PC138US, USLC-8...
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SEN01978-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 00 Index and foreword Foreword and general information Safety notice ..............................2 How to read the shop manual ......................... 7 Explanation of terms for maintenance standard ..................... 9 Handling of electric equipment and hydraulic component ................11 Handling of connectors newly used for engines ...................
Proper service and repair are extremely important for safe machine operation. The service and repair techniques recommended by Komatsu and described in this manual are both effective and safe. Some of these techniques require the use of tools specially designed by Komatsu for the specific purpose.
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00 Index and foreword SEN01978-01 When disassembling or assembling, sup- When removing piping, stop the fuel or oil port the machine with blocks, jacks, or from spilling out. If any fuel or oil drips stands before starting work. onto the floor, wipe it up immediately. Fuel Remove all mud and oil from the steps or or oil on the floor can cause you to slip other places used to get on and off the...
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SEN01978-01 00 Index and foreword Precautions for sling work and making signs Only one appointed worker must make signs and co-workers must communicate with each other frequently. The appointed sign maker must make specified signs clearly at a place where he is seen well from the operator's seat and where he can see the working condition easily.
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00 Index and foreword SEN01978-01 If the load is unstable or the wire rope 13) If the hoist stops because of a power fail- or chains are twisted, lower the load ure, turn the power switch OFF. When and lift it up again. turning on a switch which was turned OFF Do not lift up the load slantingly.
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SEN01978-01 00 Index and foreword Precautions for disconnecting and con- necting hoses and tubes in air conditioner circuit Disconnection Collect the air conditioner refriger- ant (R134a) from the air condi- tioner circuit in advance. a Ask professional traders for collecting and filling operation of refrigerant (R134a).
This section explains the method of reproducing, repairing, and replacing parts. Revision and distribution Any additions, revisions, or other change of notices will be sent to KOMATSU distributors. Get the most up-to-date information before you start any work. PC138US, USLC-8...
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SEN01978-01 00 Index and foreword Filing method File by the brochures in the correct order of the form number printed in the shop manual composition table. Revised edition mark q q q q When a manual is revised, the ones and tens digits of the form number of each brochure is increased by 1.
00 Index and foreword SEN01978-01 Explanation of terms for maintenance standard The maintenance standard values necessary for judgment of products and parts are described by the follow- ing terms. Standard size and tolerance To be accurate, the finishing size of parts is a little different from one to another.
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SEN01978-01 00 Index and foreword Standard clearance and standard value Clearance limit The clearance made when new parts are Parts can be used until the clearance assembled is called the “standard clear- between them is increased to a certain ance“, which is indicated by the range limit.
00 Index and foreword SEN01978-01 Handling of electric equipment and hydraulic component To maintain the performance of the machine over a long period, and to prevent failures or other troubles before they occur, correct “operation“, “maintenance and inspection“, “troubleshooting“, and “repairs” must be carried out.
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SEN01978-01 00 Index and foreword Disconnections in wiring If the wiring is held and the connectors are pulled apart, or components are lifted with a crane with the wiring still connected, or a heavy object hits the wiring, the crimping of the connector may separate, or the sol- dering may be damaged, or the wiring may be broken.
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00 Index and foreword SEN01978-01 Removing, installing, and drying connec- tors and wiring harnesses Disconnecting connectors Hold the connectors when discon- necting. When disconnecting the connectors, hold the connectors. For connectors held by a screw, loosen the screw fully, then hold the male and female connectors in each hand and pull apart.
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SEN01978-01 00 Index and foreword Connecting connectors Check the connector visually. Check that there is no oil, dirt, or water stuck to the connector pins (mating portion). Check that there is no deformation, defective contact, corrosion, or dam- age to the connector pins. Check that there is no damage or breakage to the outside of the con- nector.
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00 Index and foreword SEN01978-01 Heavy duty wire connector (DT 8-pole, 12- Disconnection Connection (Example of pole) incomplete setting of (a)) Disconnection (Left of figure) While pressing both sides of locks (a) and (b), pull out female connector (2). Connection (Right of figure) Push in female connector (2) horizon- tally until the lock clicks.
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SEN01978-01 00 Index and foreword Drying wiring harness If there is any oil or dirt on the wiring har- ness, wipe it off with a dry cloth. Avoid washing it in water or using steam. If the connector must be washed in water, do not use high-pressure water or steam directly on the wiring harness.
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00 Index and foreword SEN01978-01 Handling controller The controller contains a microcomputer and electronic control circuits. These con- trol all of the electronic circuits on the machine, so be extremely careful when handling the controller. Do not place objects on top of the control- ler.
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SEN01978-01 00 Index and foreword Points to remember when handling hydraulic equipment With the increase in pressure and precision of hydraulic equipment, the most common cause of failure is dirt (foreign material) in the hydraulic circuit. When adding hydraulic oil, or when disassembling or assembling hydraulic equipment, it is necessary to be particularly careful.
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00 Index and foreword SEN01978-01 Change hydraulic oil when the temperature is high When hydraulic oil or other oil is warm, it flows easily. In addition, the sludge can also be drained out easily from the circuit together with the oil, so it is best to change the oil when it is still warm.
SEN01978-01 00 Index and foreword Handling of connectors newly used for engines a Mainly, following engines are object for follow- Pull lock type (PACKARD-2) ing connectors. 107 – 170, 12V140 engine 107E-1 Various temperature sensors 114E-3 Example) 125E-5 Intake air temperature sensor in 140E-5 intake manifold: TIM 170E-5...
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00 Index and foreword SEN01978-01 Push lock type 107, 114 engines Example) Fuel pressure sensor in common rail (BOSCH-03) Disconnect connector (3) according to the fol- lowing procedure. While pressing lock (C), pull out connector (3) in the direction of the arrow. 114 engine 107, 114 engine Example)
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SEN01978-01 00 Index and foreword 125 – 170, 12V140 engine Turn-housing type (Round green connector) While pressing lock (E) of the connector, 140 engine pullout connector (5) in the direction of the Example) arrow. Intake air pressure sensor in intake mani- fold (CANNON-04): PIM etc.
00 Index and foreword SEN01978-01 How to read electric wire code a The information about the wires unique to each machine model is described in Troubleshooting section, Relational information of troubleshooting. In the electric circuit diagram, the material, thickness, and color of each electric wire are indicated by sym- bols.
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SEN01978-01 00 Index and foreword Dimensions (Table 2) Nominal No. 0.5f (0.5) 0.75f (0.85) 1.25f (1.25) Number of strands/Diam- 20/0.18 7/0.32 30/0.18 11/0.32 50/0.18 16/0.32 37/0.26 26/0.32 58/0.26 41/0.32 65/0.32 eter of strand Conductor Sectional 0.51 0.56 0.76 0.88 1.27 1.29 1.96 2.09...
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00 Index and foreword SEN01978-01 Color codes table (Table 3) Color Code Color of wire Color Code Color of wire Black Light green & White Brown Light green & Yellow Brown & Black Blue & Red Brown & Red Blue & White Brown &...
SEN01978-01 00 Index and foreword Precautions when carrying out operation [When carrying out removal or installation (disassembly or assembly) of units, be sure to follow the general precautions given below when carrying out the operation.] Precautions when carrying out removal work If the coolant contains antifreeze, dispose of it correctly.
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00 Index and foreword SEN01978-01 Precautions when carrying out installation work Tighten all bolts and nuts (sleeve nuts) to the specified (KES) torque. Install the hoses without twisting or interference and fix them with intermediate clamps, if there are any. Replace all gaskets, O-rings, cotter pins, and lock plates with new parts.
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SEN01978-01 00 Index and foreword Checking muffler and exhaust pipe for damage and looseness Visually check the muffler, exhaust pipe and their mounting parts for a crack and damage. If any part is damaged, replace it. Check the mounting bolts and nuts of the muffler, exhaust pipe and their mounting parts for looseness.
00 Index and foreword SEN01978-01 Method of disassembling and connecting push-pull type coupler Before carrying out the following work, loosen the oil filler cap of the hydraulic tank gradually to release the residual pressure from the hydraulic tank. Even if the residual pressure is released from the hydraulic tank, some hydraulic oil flows out when the hose is disconnected.
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SEN01978-01 00 Index and foreword Type 2 Disconnection Hold the tightening portion and push body (7) straight until sliding prevention ring (6) contacts contact surface (a) of the hexag- onal portion at the male end. (Fig. 6) While holding the condition of Step 1), turn lever (8) to the right (clockwise).
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00 Index and foreword SEN01978-01 Type 3 Disconnection Hold the tightening portion and push body (9) straight until sliding prevention ring (8) contacts contact surface (b) of the hexag- onal portion at the male end. (Fig. 10) While holding the condition of Step 1), push cover (10) straight until it contacts contact surface (b) of the hexagonal por- tion at the male end.
SEN01978-01 00 Index and foreword Standard tightening torque table Table of tightening torques for bolts and nuts a Unless there are special instructions, tighten metric nuts and bolts to the torque below. (When using torque wrench) a The following table corresponds to the bolts in Fig. A. Thread diameter of bolt Width across flats Tightening torque...
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00 Index and foreword SEN01978-01 Table of tightening torques for split flange bolts a Unless there are special instructions, tighten split flange bolts to the torque below. Thread diameter of bolt Width across flats Tightening torque 59 – 74 6.0 – 7.5 98 –...
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SEN01978-01 00 Index and foreword Table of tightening torques for hoses (taper seal type and face seal type) a Unless there are special instructions, tighten the hoses (taper seal type and face seal type) to the torque below. a Apply the following torque when the threads are coated (wet) with engine oil. Tightening torque Nm {kgm} Taper seal Face seal...
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00 Index and foreword SEN01978-01 Table of tightening torques for 102, 107 and 114 engine series (Taper screws) a Unless there are special instructions, tighten the taper screws (unit: inch) of the 102, 107 and 114 engine series to the torque below. Thread size Tightening torque inch...
SEN01978-01 00 Index and foreword Conversion table Method of using the conversion table The conversion table in this section is provided to enable simple conversion of figures. For details of the method of using the conversion table, see the example given below. Example: Method of using the conversion table to convert from millimeters to inches Convert 55 mm into inches.
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00 Index and foreword SEN01978-01 Millimeters to inches 1 mm = 0.03937 in 0.039 0.079 0.118 0.157 0.197 0.236 0.276 0.315 0.354 0.394 0.433 0.472 0.512 0.551 0.591 0.630 0.669 0.709 0.748 0.787 0.827 0.866 0.906 0.945 0.984 1.024 1.063 1.102 1.142 1.181...
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SEN01978-01 00 Index and foreword Temperature Fahrenheit-Centigrade conversion: A simple way to convert a Fahrenheit temperature reading into a Centi- grade temperature reading or vice versa is to enter the accompanying table in the center (boldface column) of figures. These figures refer to the temperature in either Fahrenheit or Centigrade degrees. When convert from Fahrenheit to Centigrade degrees, consider the center column to be a table of Fahren- heit temperatures and read the corresponding Centigrade temperature in the column at the left.
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00 Index and foreword SEN01978-01 PC138US, USLC-8...
SEN01979-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 01 Specification Specification and technical data Specification dimension drawings ........................2 Working range diagram........................... 3 Specifications ..............................4 List of weights ............................... 10 Table of fuel, coolant and lubricants......................
01 Specification SEN01979-01 Working range diagram Working range (mm) PC138US-8 PC138USLC-8 Maximum digging reach 8,300 8,300 Maximum digging depth 5,480 5,480 Maximum digging height 9,340 9,340 Maximum vertical wall digging depth 4,900 4,900 Maximum dumping height 6,840 6,840 Minimum swing radius of work 1,980 1,980 equipment...
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SEN01979-01 01 Specification PC138US-8 Machine model Standard specification Reinforced blade specification Serial No. 20001 and up Model SAA4D95LE-5 4-cycle, water-cooled, in-line, vertical, direct injection, with Type turbocharger and air cooled aftercooler No. of cylinders-bore x stroke 95 x 115 l{cc} Piston displacement 3.260{3,260} Rated horsepower...
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01 Specification SEN01979-01 PC138USLC-8 Standard specification Reinforced blade specification 20001 and up SAA4D95LE-5 4-cycle, water-cooled, in-line, vertical, direct injection, with turbocharger and air cooled aftercooler 95 x 115 3.260{3,260} 68.4{91.7}/2,200 72.1{96.6}/2,200 350{35.7}/1,500 2,300 1,100 224{167} 24 V, 4.5 kW 24 V, 35 A 12 V, 64 Ah x 2 4-array aluminum mesh core Aluminum mesh core...
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SEN01979-01 01 Specification PC138US-8 Machine model Standard specification Reinforced blade specification Serial No. 20001 and up Type Reciprocating piston type Reciprocating piston type Cylinder inner diameter Piston rod diameter Stroke 1,055 1,055 Max. length between pins 2,555 2,555 Min. length between pins 1,500 1,500 Type...
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01 Specification SEN01979-01 PC138USLC-8 Standard specification Reinforced blade specification 20001 and up Reciprocating piston type Reciprocating piston type 1,055 1,055 2,555 2,555 1,500 1,500 Reciprocating piston type Reciprocating piston type 1,175 1,175 2,798 2,798 1,623 1,623 Reciprocating piston type Reciprocating piston type 2,263 2,263 1,378...
SEN01979-01 01 Specification List of weights This weight table is prepared for your reference when handling or transporting the components. Unit: kg PC138US-8 Machine model Standard specification Blade specification Serial No. 20001 and up Engine assembly (excl. coolant and oil) •...
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01 Specification SEN01979-01 Unit: kg PC138USLC-8 Standard specification Blade specification 20001 and up 18.1 18.1 (6 x 2) (6 x 2) 82.2 82.2 10.2 10.2 1,400 1,400 90.6 90.6 79.5 79.5 3,240 2,855 152.6 152.6 71.6 71.6 28.6 43.6 2,540 2,680 1,460 1,600...
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SEN01979-01 01 Specification Unit: kg PC138US-8 Machine model Standard specification Blade specification Serial No. 20001 and up Boom assembly Arm assembly Bucket link assembly 85.6 85.6 Bucket assembly — — • 955 mm width (incl. side cutter) • 980 mm width (incl. side cutter) Blade assembly —...
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01 Specification SEN01979-01 Unit: kg PC138USLC-8 Standard specification Blade specification 20001 and up 85.6 85.6 — — — — — — 101.3 x 2 101.3 x 2 125.3 125.3 77.8 77.8 — 59.5 x 2 PC138US, USLC-8...
SEN01979-01 01 Specification Table of fuel, coolant and lubricants a For details of the notes (Note. 1, Note. 2 …) in the table, see the Operation and Maintenance Manual. PC138US, USLC-8...
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01 Specification SEN01979-01 Unit: l Reservoir Specified capacity Refill capacity Engine oil pan 11.5 11.0 Swing machinery case Final drive case (each side) PTO case 0.75 0.75 Hydraulic system Fuel tank — Cooling system 12.4 — PC138US, USLC-8...
SEN02545-01 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Engine and cooling system Engine mount..............................2 PTO................................. 3 Cooling system ............................... 4 PC138US, USLC-8...
10 Structure, function and maintenance standard SEN02545-01 a PTO: Abbreviation for Power Take Off Flywheel Coupling Hydraulic pump shaft Drain plug Oil filler plug Oil level plug PC138US, USLC-8...
SEN02546-01 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Power train Power train..............................2 Swing circle..............................3 Swing machinery............................. 4 PC138US, USLC-8...
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SEN02546-01 10 Structure, function and maintenance standard Power train Idler Travel junction solenoid valve Control valve Travel motor 2a. Self pressure reducing valve Hydraulic pump 2b. Pump merge-divider valve 10. Engine 2c. Travel junction valve 11. Swing motor PPC lock solenoid valve 12.
10 Structure, function and maintenance standard SEN02546-01 Swing circle Unit: mm Item Criteria Remedy Basic clearance Clearance limit Bearing clearance Replace 0.5 – 1.6 Swing circle bearing lubrication Inner race soft zone position Swing circle pinion lubrication Outer race soft zone position Outer race Ball Specifications...
SEN02546-01 10 Structure, function and maintenance standard Swing machinery Level gauge Specifications Oil feed pipe Reduction ratio (14+61) / 14 × (17+61) / 17 = 24.58 Oil filler cap Swing reduction Swing pinion (Number of teeth: 11) 24.58 × 8.182 = 201.11 ratio Swing machinery case No.
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10 Structure, function and maintenance standard SEN02546-01 Unit: mm Item Criteria Remedy Standard clearance Clearance limit Backlash between swing motor shaft and No. 1 sun gear 0.07 – 0.18 Backlash between No. 1 sun 0.13 – 0.31 gear and No. 1 planetary gear Backlash between No.
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SEN02547-01 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Undercarriage and frame Track frame ..............................2 Idler cushion..............................4 Idler ................................. 6 Track roller ..............................7 Carrier roller ..............................
SEN02547-01 10 Structure, function and maintenance standard Track frame PC138US-8 Unit: mm Item Criteria Remedy Standard size Repair limit Rebuilding Track Length at idler guide frame Idler Rebuilding or support replace Track Rebuilding frame Width at idler guide Idler Rebuilding or support replace Idler...
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10 Structure, function and maintenance standard SEN02547-01 PC138USLC-8 Unit: mm Item Criteria Remedy Standard size Repair limit Rebuilding Track Length at idler guide frame Idler Rebuilding or support replace Track Rebuilding frame Width at idler guide Idler Rebuilding or support replace Idler Track frame...
SEN02547-01 10 Structure, function and maintenance standard Idler Unit: mm Item Criteria Remedy Standard size Repair limit Outside diameter of projection — Rebuilding or Outside diameter of tread replace Tread depth Width of projection Overall width — Rebuilding or Tread width 31.5 36.5 replace...
10 Structure, function and maintenance standard SEN02547-01 Track roller Unit: mm Item Criteria Remedy Standard size Repair limit Outside diameter of projection — Rebuilding or replace Outside diameter of tread Flange width 26.5 — Overall width — — Rebuilding or Tread width —...
SEN02547-01 10 Structure, function and maintenance standard Carrier roller Unit: mm Item Criteria Remedy Standard size Repair limit Rebuilding or Outside diameter of tread replace Tread width — — Tolerance Standard Standard Clearance size clearance limit Clearance between shaft and Shaft Hole bushing...
10 Structure, function and maintenance standard SEN02547-01 Sprocket Unit: mm Item Criteria Remedy Standard size Tolerance Repair limit Wear on tooth bottom diameter +1.0 542.8 -2.0 Wear on tooth tip diameter 607.5 — Rebuilding or replace Wear on tooth tip width —...
SEN02547-01 10 Structure, function and maintenance standard Track shoe Triple grouser shoe, road liner, city pad shoe *1. Triple grouser shoe, city pad shoe *2. Road liner a P portion shows the link of bushing press fitting end. PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02547-01 Unit: mm Item Criteria Remedy Standard size Repair limit Link pitch 175.3 178.3 Reverse or Standard size Reverse replace Bushing external diameter 50.6 46.6 Bushing thickness Standard size Repair limit Repair or Link height replace Link thickness (bushing press fit 23.9...
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SEN02547-01 10 Structure, function and maintenance standard Unit: mm Item Criteria Remedy Tightening torque (Nm {kgm}) Retightening angle (degree) • Triple grouser shoe 196 ± 20 a. Regu- 90 ± 10 • City pad shoe {20 ± 2} lar link •...
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10 Structure, function and maintenance standard SEN02547-01 Triple grouser shoe Unit: mm Item Criteria Remedy Standard size Repair limit Grouser overall height Shoe overall height 29.5 19.5 Plate thickness Rebuilding or replace Grouser bottom length Grouser tip length PC138US, USLC-8...
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SEN02547-01 10 Structure, function and maintenance standard Single shoe Unit: mm Item Criteria Remedy Standard size Repair limit Grouser overall height 20.5 Shoe overall height 32.5 Rebuilding or replace Plate thickness Grouser bottom length Grouser tip length PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02547-01 PC138US, USLC-8...
SEN02548-01 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Hydraulic system, Part 1 Hydraulic equipment layout drawing ....................... 2 Valve control ..............................4 Hydraulic tank and filter ..........................6 Hydraulic pump ...............................
SEN02548-01 10 Structure, function and maintenance standard Hydraulic equipment layout drawing Bucket cylinder Arm cylinder Control valve Solenoid valve Accumulator (for PPC circuit) Boom cylinder Hydraulic tank Swing motor Hydraulic pump 10. R.H. travel motor 11. Oil cooler 12. L.H. travel motor 13.
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10 Structure, function and maintenance standard SEN02548-01 PC138US, USLC-8...
SEN02548-01 10 Structure, function and maintenance standard Hydraulic tank and filter Hydraulic tank Specifications Suction strainer Hydraulic tank capacity (l) Filter element Bypass valve Oil level in hydraulic tank (l) Drain plug Bypass valve set pressure 0.15 ± 0.03 Sight gauge (MPa{kg/cm²}) {1.53 ±...
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10 Structure, function and maintenance standard SEN02548-01 Breather Filter element Bottom plate Gasket Seam valve Spring Prevention of negative pressure in tank The hydraulic tank is enclosed and pressur- ized. When the oil level in the hydraulic tank drops, negative pressure is generated in the tank.
SEN02548-01 10 Structure, function and maintenance standard Hydraulic pump Type: HPD56+56 PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02548-01 Outline This pump consists of a variable-displacement swash plate type piston pump, PC valve, LS valve and EPC valve. Features of double pump system The common single pump system makes much loss in the pressure compensation valve. Accordingly, the machine travel speed is reduced much when the machine is steered.
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SEN02548-01 10 Structure, function and maintenance standard Shaft Cylinder block Cradle Valve plate Case End cap Rocker cam 10. Servo piston Shoe 11. PC valve Piston PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02548-01 Function Rocker cam (4) conducts high pressure oil to the cylinder surface (B) with cradle (2), which The pump converts the engine rotation and is secured to the case, and forms a static pres- torque transmitted to its shaft to oil pressure sure bearing when it slides.
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SEN02548-01 10 Structure, function and maintenance standard Operation of pump Cylinder block (7) rotates together with shaft As center line (X) of rocker cam (4) matches (1), and shoe (5) slides on flat surface (A). the axial direction of cylinder block (7) (swash When this happens, rocker cam (4) moves plate angle (a) = 0), the difference between along cylindrical surface (B), so angle (a)
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10 Structure, function and maintenance standard SEN02548-01 Control of delivery If the swash plate angle (a) becomes larger, the difference between volumes (E) and (F) b ec o me s l ar g er a nd pu m p d el i v e r y ( Q ) increases.
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SEN02548-01 10 Structure, function and maintenance standard LS valve : Pump port Sleeve 7. Plug PDP : Drain port Piston 8. Locknut PLP : LS control pressure output port Spool PLS : LS pressure input port Spring : Pump port Sheet PPL : Control pressure input port Sleeve...
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10 Structure, function and maintenance standard SEN02548-01 Operation 1. When the control valve is situated at neutral The LS valve is a 3-way selector valve, with Pump pressure (PP) is conducted to the larger pressure (PLS) (LS pressure) from the outlet diameter end from the port (K).
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SEN02548-01 10 Structure, function and maintenance standard 2. Action for the direction of maximizing the pump delivery When the difference between the main pump pressure (PP) and LS pressure (PLS), in other words, LS differ ential press ure ( P LS) becomes smaller [for example, when the area of opening of the control valve becomes larger and pump pressure (PP) drops], spool (6) is...
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10 Structure, function and maintenance standard SEN02548-01 3. Action for the direction of minimizing the pump delivery When differential pressure ( PLS) becomes larger [for example, when the area of opening of the control valve becomes smaller and pump pressure (PP) rises] because of the leftward move (it reduces delivery) of servo piston (12), pump pressure (PP) pushes spool (6) to the left.
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SEN02548-01 10 Structure, function and maintenance standard 4. When servo piston is balanced Let us take the area receiving the pressure at Force of spring (4) is adjusted in such that the the large diameter end of the piston as (A1), position of the balanced stop of this spool (6) the area receiving the pressure at the small may be determined when (PP) —...
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10 Structure, function and maintenance standard SEN02548-01 PC valve : Pump port Plug PA2 : Pump pressure pilot port Servo piston assembly PDP : Drain port PM : Mode selector pressure pilot port Spool PPL : PC control pressure output port Retainer PPL2: LC control pressure output port Sheet...
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SEN02548-01 10 Structure, function and maintenance standard Operation 1. When pump controller is normal When the load on the actuator is small and pump discharge pressures (PP1) and (PP2) are low Action of PC-EPC valve solenoid (1) Command current (X) is being sent to PC-EPC The pressure [port (C) pressure] output from valve solenoid (1) from the pump controller.
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10 Structure, function and maintenance standard SEN02548-01 PC138US, USLC-8...
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SEN02548-01 10 Structure, function and maintenance standard Action of spring Load of springs (4) and (6) on the PC valve is Spring load of springs (4) and (6) is also determined by the swash plate position. affected by the command current (X) to PC- As servo piston (9) moves to left, spring (6) is EPC valve solenoid.
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10 Structure, function and maintenance standard SEN02548-01 If port (E) and port (G) of the LS valve are con- nected, the pressure entering the large diame- ter end of the piston from port (J) becomes drain pressure (PT), and servo piston (9) moves to the right side.
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SEN02548-01 10 Structure, function and maintenance standard When load on actuator is large and pump discharge pressure is high Outline Operation When the load is large and pump discharge When port (E) and port (G) of the LS valve are pressures (PP1) and (PP2) are high, the force connected, this pressure from port (J) enters pushing spool (3) to the left becomes larger...
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10 Structure, function and maintenance standard SEN02548-01 As a result, the pressure on port (C) (= J) is decreased and the rightward move of servo piston (9) is stopped. The position in which servo piston (9) stops at this time is further to the left than the position when pump pressures (PP1) and (PP2) are low.
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SEN02548-01 10 Structure, function and maintenance standard 2. As the emergency pump drive switch is turned on due to failure on the pump controller When the main pump is under light load If there is a failure in the pump controller, the If the main pump pressures (PP1) and (PP2) emergency pump drive switch is turned on to are low, the combined force of the pump pres-...
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10 Structure, function and maintenance standard SEN02548-01 When the main pump is under heavy load If the emergency pump drive switch is turned on in the same way as in above, the command current (X) sent to PC-EPC valve solenoid (1) becomes constant.
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SEN02548-01 10 Structure, function and maintenance standard When the emergency pump drive switch is turned on, too, the pump pressure (PP) and pump delivery (Q) have a relationship as shown with the curve in the figure correspond- ing to the current sent to the PC-EPC valve solenoid through the resistor.
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10 Structure, function and maintenance standard SEN02548-01 PC-EPC valve C : To PC valve P : From self pressure reducing valve T : To tank Connector Coil Body Spring Spool Plunger PC138US, USLC-8...
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SEN02548-01 10 Structure, function and maintenance standard Function Operation The EPC valve consists of the proportional 1. When signal current is 0 (coil is de- solenoid portion and the hydraulic valve por- energized) tion. When it receives signal current (i) from the When there is no signal current flowing from controller, it generates the EPC output pres- the controller to coil (2), coil (2) is de-ener-...
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10 Structure, function and maintenance standard SEN02548-01 2. When signal current is very small 3. When signal current is maximum (coil is energized) (coil is energized) When a very small signal current flows to coil As the signal current flows to coil (2), coil (2) is (2), coil (2) is energized, and a propulsion force energized.
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SEN02548-01 10 Structure, function and maintenance standard Check valve PA1: Discharge pressure of main pump Poppet valve PA2: Discharge pressure of main pump Poppet valve PP1: Output pressure of check valve Function Operation A set of 2 check valves is used to select and 1.
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10 Structure, function and maintenance standard SEN02548-01 Shuttle valve PA1: Discharge pressure of main pump PA2: Discharge pressure of main pump PP2: Output pressure of shuttle valve Poppet valve Poppet valve Function Operation The shuttle valve selects and outputs the lower The discharge pressures (PA1) and (PA2) of discharge pressure of the 2 main pumps.
SEN02549-02 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Hydraulic system, Part 2 Control valve ..............................2 CLSS................................14 Functions and operation by valve ......................... 18 PC138US, USLC-8...
SEN02549-02 10 Structure, function and maintenance standard Control valve Outline The control valves of the following types are set. 6-spool valve (Without service valve) 7-spool valve (6-spool valve + service valve) 7-spool valve (Blade) 8-spool valve (Blade + service valve) 8-spool valve (6-spool valve + 2 service valves) 9-spool valve (Blade + 2 service valves) The appearance and section of only the 8-spool valve (blade + service valve) are shown here.
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10 Structure, function and maintenance standard SEN02549-02 PC138US, USLC-8...
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SEN02549-02 10 Structure, function and maintenance standard PC138US, USLC-8...
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SEN02549-02 10 Structure, function and maintenance standard PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02549-02 LS selector valve Cooler bypass valve Pressure compensation valve R (Service) Pressure compensation valve R (Bucket) Pressure compensation valve R (Arm) Pressure compensation valve R (Boom) Pressure compensation valve R (Right travel) Pressure compensation valve R (Left travel) Pressure compensation valve R (Blade) 10.
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SEN02549-02 10 Structure, function and maintenance standard PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02549-02 LS selector valve Swing valve Pressure compensation valve F Spool Pressure compensation valve R Swing bleed valve Blade valve Suction safety valve Suction valve Spool Pressure compensation valve R 10. Pressure compensation valve F L.H.
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SEN02549-02 10 Structure, function and maintenance standard PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02549-02 R.H. Travel valve Pressure compensation valve F Suction valve Suction valve Spool Pressure compensation valve R Travel junction valve + LS check valve Unload valve LS bypass valve Merge-divider valve spool 10. Main relief valve 11.
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SEN02549-02 10 Structure, function and maintenance standard PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02549-02 Arm valve Pressure compensation valve F Suction valve Suction valve Spool Pressure compensation valve R Regeneration valve Bucket valve Pressure compensation valve F Suction valve Suction valve 10. Spool 11. Pressure compensation valve R Service valve 12.
SEN02549-02 10 Structure, function and maintenance standard CLSS Outline of CLSS Features Configuration CLSS stands for Closed center Load Sensing Sys- CLSS is configured with variable capacity tem, which has the following characteristics: piston pumps, control valves, and respective actuators. Fine control not influenced by load The hydraulic pump is configured with pump Controllability enabling digging even with fine...
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10 Structure, function and maintenance standard SEN02549-02 Basic principle 1. Pump swash plate angle control The pump swash plate angle (pump delivery) The pump swash plate angle shifts toward the is controlled so that LS differential pressure maximum position if LS differential pressure ( P L S ) ( t h e d i ff e r e n c e b e t w e e n p u m p ( PLS) is lower than the set pressure of the pressure PP and control valve outlet port LS...
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SEN02549-02 10 Structure, function and maintenance standard 2. Pressure compensation control A pressure compensation valve is installed to the outlet port side of the control valve to bal- ance the load. When actuators are operated together, the p r e s s u r e d i ff e r e n c e ( P ) b e t w e e n t h e upstream (inlet port) and downstream (outlet port) of the spool of each valve becomes the same regardless the size of the load (pres-...
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10 Structure, function and maintenance standard SEN02549-02 PC138US, USLC-8...
SEN02549-02 10 Structure, function and maintenance standard Functions and operation by valve Hydraulic circuit diagram and the name of valves PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02549-02 Swing valve Blade valve Left travel valve Right travel valve Boom valve Arm valve Bucket valve Service valve Swing spool 10. Blade spool 11. Left travel spool 12. Right travel spool 13. Boom spool 14.
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SEN02549-02 10 Structure, function and maintenance standard Unload valve 1. When control valve is at HOLD Function When the control valve is at HOLD, LS pres- sures (LS1) and (LS2) are not generated, so When the control valve is at HOLD, pump only pump discharge pressures (P1) and (P2) delivery (Q) discharged by the minimum swash act, and (P1) and (P2) are set by only the load...
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10 Structure, function and maintenance standard SEN02549-02 2. When work equipment valve is operated Function Operation When any work equipment valve is operated if When any work equipment valve is operated the demand flow for the actuator becomes for a long stroke, LS pressures (LS1) and greater than the pump discharge from the min- (LS2) are generated and act on the face (SB) imum swash plate angle, the oil flow to tank cir-...
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SEN02549-02 10 Structure, function and maintenance standard 3. During fine control of both travel valves Function Operation When the difference between pump discharge When fine control is carried out on both travel pressure (P1) and (P2) and LS pressure (LS1) valves, LS pressures (LS1) and (LS2) are gen- and (LS2) reaches the load of spring (2), erated and act on the face (SB) of spool (1)
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10 Structure, function and maintenance standard SEN02549-02 4. When both travel valves are operated Function Operation During operation of both travel valves, when When both travel valves are operated to the the demand flow becomes maximum, the oil stroke ends, LS pressures (LS1) and (LS2) are flow to tank circuit (T) is cut off, and all pump generated and act on the face (SB) of unload delivery (Q) flows to both travel circuits.
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SEN02549-02 10 Structure, function and maintenance standard 5. When either travel valve is operated Function The area of the openings of left travel valve spool is large, so LS pressures (LS1) is not so The demand flow decided by the valve stroke different from pump discharge pressures (P1).
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10 Structure, function and maintenance standard SEN02549-02 PC138US, USLC-8...
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SEN02549-02 10 Structure, function and maintenance standard Merge-divider valve 1. When oil is merged: (PS) = 0 kg/cm Function Pump discharge pressures (P1) and (P2) are merged in pump merge-divider spool (3). (LS1), (LS2), and (LS3) are also merged. At this time, (P1) = (P2) and (LS1) = (LS2) = (LS3) and the pump swash plate is controlled by the difference between (P) and (LS).
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10 Structure, function and maintenance standard SEN02549-02 2. When oil is divided: (PS) = 30 kg/cm Function Pump discharge pressures (P1) and (P2) are divided in pump merge-divider spool (3). (LS1), (LS2), and (LS3) are also divided. At this time, higher one of (P1) and (P2) is applied through pump merge-divider spool (3) to the output port of the LS pressure.
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SEN02549-02 10 Structure, function and maintenance standard Introduction of LS pressure 1. Work equipment valve Function When this happens, LS circuit (PLS) is con- nected to tank circuit (T) from LS bypass valve The LS pressure is the actuator load pressure (4) (See the section on the LS bypass valve).
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10 Structure, function and maintenance standard SEN02549-02 2. Travel valve Operation When spool (1) is operated, pump discharge pressure (PP) flows from flow control valve (2) through notch (a) in the spool and bridge pas- sage (b) to actuator circuit (A). Actuator circuit pressure (PA) (= A) is intro- duced through the check valve (5) into LS cir- cuit (PLS).
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SEN02549-02 10 Structure, function and maintenance standard LS bypass valve 1. When work equipment valve is operated (including compound operation of work equipment + travel) Function Operation The LS bypass valve releases the remaining Since pump merge-divider spool (1) is at the pressure of LS pressure (PLS).
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10 Structure, function and maintenance standard SEN02549-02 2. When either or both travel valves are operated (Including operation of only one travel valve) Operation The hydraulic oil (PLS2) flows from tip filter (c) of LS bypass valve (3) through orifice (d) to Since pump merge-divider spool (1) is at the tank circuit (T).
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SEN02549-02 10 Structure, function and maintenance standard Pressure compensation valve PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02549-02 Function When the load pressure becomes lower than another actuator and the flow is going to increase during a compound operation, this valve compensates the load pressure. [At the time, the load pressure of another actuator under compound operation (the upper side) is higher than that of the actuator on this side (the lower side)].
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SEN02549-02 10 Structure, function and maintenance standard Area ratio of pressure compensation valve Function Area ratio (S1) : (S2) and compensation charac- teristics The pressure compensation valve slightly When the ratio is 1.00 : adjusts the ratio (S2) and (S1) of the area (S1) The expression [Pump (discharge) pres- on the left side of the flow control valve (2) and sure (PP) –...
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10 Structure, function and maintenance standard SEN02549-02 Boom regeneration circuit 1. At boom lower and own weight fall Function At the time, part of the return flow on the bot- tom side passes through the regeneration pas- When the boom is lowered and falls due to its sage (a) of the boom spool (2), pushes the own weight because the bottom pressure (A) check valve (3) to open it and flows to the head...
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SEN02549-02 10 Structure, function and maintenance standard 2. At boom lower load process Function At the time, the head side pressure (B) and the spring (4) close the check valve (3), and the When the head pressure (B) of the cylinder (1) circuits on the head side and the bottom side is higher than the bottom pressure (A) while are interrupted.
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10 Structure, function and maintenance standard SEN02549-02 Arm regeneration circuit 1. At arm in and own weight fall : Head circuit Arm cylinder : Bottom circuit Arm spool PP : Pump circuit Check valve Function At the time, part of the return flow on the head side passes through the regeneration passage When the arm falls due to its own weight (a) of the arm spool (2), pushes the check...
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SEN02549-02 10 Structure, function and maintenance standard 2. At arm in process : Head circuit Arm cylinder : Bottom circuit Arm spool PP : Pump circuit Check valve Function When the bottom pressure (B) of the cylinder (1) rises above the head pressure (A) and the arm enters the digging process, the check valve (3) will be closed and the circuits on the head side and the bottom side will be inter-...
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10 Structure, function and maintenance standard SEN02549-02 Hydraulic drift prevention valve 1. When boom is raised Function Operation While the boom lever is not operated, the If the boom is raised out, the main pressure hydraulic drift prevention valve prevents pres- from the control valve pushes up poppet (5).
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SEN02549-02 10 Structure, function and maintenance standard 2. When boom and arm are set in neutral Operation If the control lever is returned to the neutral position while the boom is raised out, the hold- ing pressure in the boom cylinder bottom and arm cylinder head is blocked by poppet (5) and the pressurized oil flowing in through orifice (a) is blocked by pilot spool (3).
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10 Structure, function and maintenance standard SEN02549-02 3. When boom is lowered Operation If the boom is lowered, pilot pressure (P1) from the PPC valve pushes pilot spool (3) and the pressurized oil in chamber (b) in the poppet is drained.
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SEN02549-02 10 Structure, function and maintenance standard Swing bleeding valve Function Accordingly, the intermediate pressure is set lower than pump discharge pressure (PP) and When the machine swings, the bleeding valve raised as bleeding spool (3) moves. As a installed to the pressure reducing valve works result, LS pressure (PLS) rises gradually.
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10 Structure, function and maintenance standard SEN02549-02 LS select valve 1. During normal operation Function At the time of simultaneous operation of swing + boom RAISE, this valve prevents high swing LS pressure from entering the LS circuit (PLS) and also prevents the boom RAISE speed from reducing by securing the pump flow at the time of swing drive.
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SEN02549-02 10 Structure, function and maintenance standard 2. At simultaneous operation of swing + boom RAISE Operation At the simultaneous operation of swing + boom RAISE, the signal pressure of the PPC circuit is led to the pilot port (BP). When this pilot pressure (BP) is applied to the piston (2) and reaches a pressure that is stron- ger than the spring (3), the piston (2) will be...
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10 Structure, function and maintenance standard SEN02549-02 Travel junction valve Function Operation This valve connects both travel circuits to each When pilot pressure is turned ON other so that hydraulic oil will be supplied If the pilot pressure from the travel junction evenly to both travel motors and the machine solenoid valve becomes higher than the force will travel straight.
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SEN02549-02 10 Structure, function and maintenance standard Self pressure reducing valve Function When abnormally high pressure is generated The self pressure reducing valve lowers the If the (PR) pressure of the self pressure reduc- discharge pressure of the main pump and sup- ing valve is raised abnormally, ball (6) sepa- plies it as the control pressure for the solenoid rates from the seat against the force of spring...
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10 Structure, function and maintenance standard SEN02549-02 Lift check valve and cooler bypass valve Lift check valve Cooler bypass valve Function Function The lift check valve generates back pressure in The cooler bypass valve protects oil cooler (4) the drain circuit to prevent negative pressure from breakage when the return flow rate from on each actuator (motor, cylinder, etc.) the control valve increases and oil cooler inlet...
SEN02550-01 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Hydraulic system, Part 3 PPC valve ............................... 2 Swing motor ..............................19 Travel motor ..............................27 Center swivel joint............................36 Solenoid valve...............................
SEN02550-01 10 Structure, function and maintenance standard PPC valve Work equipment and swing PPC valve : From self pressure reducing valve P1 : L.H. PPC valve: Arm OUT port/R.H. PPC valve: Boom LOWER port P2 : L.H. PPC valve: Arm IN port/R.H. PPC valve: Boom RAISE port P3 : L.H.
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10 Structure, function and maintenance standard SEN02550-01 PC138US, USLC-8...
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SEN02550-01 10 Structure, function and maintenance standard Spool Piston Disc Nut (for lever connection) Joint Plate Retainer Body Filter Unit: mm Check item Criteria Remedy Standard size Repair limit Free length Installation Installation Installation Centering spring × Outside Free length length load load...
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10 Structure, function and maintenance standard SEN02550-01 Operation The relationship of the position of spool (1) and body (10) [fine control hole (f) is in the middle 1. When in neutral between drain chamber (D) and pump pres- sure chamber (PP)] does not change until Ports (A) and (B) of the control valve and ports retainer (9) contacts spool (1).
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SEN02550-01 10 Structure, function and maintenance standard 3. During fine control 4. At full stroke (When control lever is returned) Disc (5) pushes down piston (4), and retainer (9) pushes down spool (1). When disc (5) starts to be returned, spool (1) is Fine control hole (f) is shut off from drain pushed up by the force of centering spring (3) chamber (D), and is interconnected to pump...
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10 Structure, function and maintenance standard SEN02550-01 Travel PPC valve : From self pressure reducing valve P1 : L.H. reverse P2 : L.H. forward P3 : R.H. reverse P4 : R.H. forward : To tank PC138US, USLC-8...
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SEN02550-01 10 Structure, function and maintenance standard PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02550-01 Plate Body Piston Seal Valve Damper Unit: mm Check item Criteria Remedy Standard size Repair limit Free length Installation Installation Installation × Outside Free length Centering spring length load load If damaged or diameter deformed, 48.57 ×...
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SEN02550-01 10 Structure, function and maintenance standard Operation The relationship of the position of spool (1) and body (10) [fine control hole (f) is in the middle 1. When in neutral between drain chamber (D) and pump pres- sure chamber (PP)] does not change until Ports (A) and (B) of the control valve and ports retainer (9) contacts spool (1).
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10 Structure, function and maintenance standard SEN02550-01 3. During fine control 4. At full stroke (When control lever is returned) Lever (5) pushes down piston (4), and retainer (9) pushes down spool (1). When lever (5) starts to be returned, spool (1) Fine control hole (f) is shut off from drain is pushed up by the force of centering spring chamber (D), and is interconnected to pump...
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SEN02550-01 10 Structure, function and maintenance standard Blade PPC valve a For the details of operation, see the paragraph of "Work equipment and swing PPC valve". PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02550-01 : From self pressure reducing valve P1 : To blade valve P2 : To blade valve : To tank Spool Piston Lever Plate Retainer Body Filter Unit: mm Check item Criteria Remedy Standard size Repair limit Free length Installation...
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SEN02550-01 10 Structure, function and maintenance standard Attachment PPC valve (with EPC valve) a For the details of operation, see the paragraph of "Work equipment and swing PPC valve". PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02550-01 : From self pressure reducing valve P1 : To service valve P2 : To service valve : To tank Spool Piston Lever Plate Retainer Block Body EPC valve Unit: mm Check item Criteria Remedy Standard size Repair limit...
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SEN02550-01 10 Structure, function and maintenance standard 1. EPC valve C: To control valve Spool From self pressure reducing valve Push pin To hydraulic tank Coil Plunger Body Connector Plug Unit: mm Check item Criteria Remedy Standard size Repair limit If damaged or Installation Installation...
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10 Structure, function and maintenance standard SEN02550-01 Function Operation The EPC valve consists of the proportional 1) When signal current is 0 solenoid portion and the hydraulic valve por- (coil is de-energized) tion. When it receives signal current (i) from the When there is no signal current flowing from pump controller, it generates the EPC output the controller to coil (14), coil (14) is de-ener-...
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SEN02550-01 10 Structure, function and maintenance standard 2) When signal current is very small 3) When signal current is maximum (coil is energized) (coil is energized) When a very small signal current flows to coil As the signal current flows to coil (5), coil (5) is (5), coil (5) is energized, and a propulsion force energized.
10 Structure, function and maintenance standard SEN02550-01 Swing motor Type: KMF45ABE-5 From swing holding brake solenoid valve Specifications MA: From control valve Type : KMF45ABE-5 MB: From control valve Theoretical displacement : 143.8 cm³/rev From control valve Safety valve set pressure : 27.1 MPa {276 kg/cm²} To tank Rated speed : 2,111 rpm...
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SEN02550-01 10 Structure, function and maintenance standard PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02550-01 Brake spring Drive shaft Spacer Case Disc Plate Brake ring Brake piston Housing 10. Piston 11. Cylinder block 12. Valve plate 13. Center shaft 14. Center spring 15. Check valve 16. Shuttle valve Unit: mm Check item Criteria...
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SEN02550-01 10 Structure, function and maintenance standard Swing holding brake When solenoid valve is de-energized When solenoid valve is energized Operation Operation As the swing holding brake solenoid valve is As the swing holding brake solenoid valve is de-energized, the pressurized oil from the self energized, the valve is switched.
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10 Structure, function and maintenance standard SEN02550-01 Relief valve portion Outline When swing is stopped The relief valve portion consists of check When the swing control lever is returned to valves (2) and (3), shuttle valves (4) and (5), neutral, the supply of pressurized oil from the and relief valve (1).
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SEN02550-01 10 Structure, function and maintenance standard Reverse prevention valve PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02550-01 MA: From control valve MB: From control valve T1: To tank T2: To tank Valve body Spool (MA side) Spring (MA side) Plug (MA side) Spool (MB side) Spring (MB side) Plug (MB side) Explanatory drawing of effects PC138US, USLC-8...
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SEN02550-01 10 Structure, function and maintenance standard Function When motor is stopped temporarily This valve reduces the swing back generation The motor rotation is reversed by the closing in the swing body by the inertia of the swing pressure generated at port (MB). (1st time: body, the backlash and rigidity of the machin- reverse rotation) ery system, and the compression of the...
10 Structure, function and maintenance standard SEN02550-01 Travel motor From center swivel joint, port B2 (L.H. travel motor) From center swivel joint, port C2 (R.H. travel motor) From center swivel joint, port D2 (L.H. travel motor) From center swivel joint, port A2 (R.H.
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SEN02550-01 10 Structure, function and maintenance standard Plug 16. Cover Check valve 17. Sun gear A Counterbalance valve 18. Carrier A Sleeve 19. Sun gear B Relief valve 20. Carrier B End cover 21. Regulator piston Brake piston 22. Shaft Disc 23.
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10 Structure, function and maintenance standard SEN02550-01 Specifications Type GM21VA-A 44.2 Stroke volume (cm³/rev) 79.1 2,609 Rated speed (rpm) 1,486 Brake releasing pressure 0.76 (MPa{kg/cm²}) {7.71} Hi-Lo switching pressure 2.94 (MPa{kg/cm²}) {30} Reduction ratio 54.0 Outline Final drive 2nd travel speed selector mechanism Consists of 2-stage planetary gear mecha- Consists of the regulator valve and regulator nism.
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SEN02550-01 10 Structure, function and maintenance standard Operation Operation of motor At low speed (the motor swash plate angle is maximized.) 2nd travel speed select solenoid valve Since 2nd travel speed select solenoid valve Regulator valve (1) is de-energized, the pressurized oil from Spring self pressure reduction valve (11) is not fed to Check valve...
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10 Structure, function and maintenance standard SEN02550-01 At high speed (the motor swash plate angle is minimized.) 2nd travel speed select solenoid valve When 2nd travel speed select solenoid valve Regulator valve (1) is energized, the pressurized oil from self Spring pressure reduction valve (11) is fed to port (P).
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SEN02550-01 10 Structure, function and maintenance standard Brake valve Operation when pressure oil is supplied Operation when pressure is shut off When the travel lever is operated, the pressur- When the travel lever is returned to its neutral ized oil from the control valve is fed to port (A) position, the hydraulic oil circuit from the con- and check valve (1) is opened.
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10 Structure, function and maintenance standard SEN02550-01 Brake operation at travelling downhill If the machine is going to run away when trav- eling downhill, the motor idles and the hydrau- lic pressure at port (C) drops. The pressure of hydraulic oil that is sent to chamber (G) through orifice (f) also drops.
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SEN02550-01 10 Structure, function and maintenance standard Relief valve When starting When stopping The pressurized oil from the control valve is When the hydraulic oil from the control valve is fed from port (A) to port (C). As port (C) is con- stopped, ports (A) and (C) are closed.
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10 Structure, function and maintenance standard SEN02550-01 PC138US, USLC-8...
SEN02550-01 10 Structure, function and maintenance standard Center swivel joint Standard specification From control valve (R.H. travel FORWARD) To R.H. travel motor port B From control valve (L.H. travel FORWARD) To L.H. travel motor port A From control valve (R.H. travel REVERSE) To R.H.
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10 Structure, function and maintenance standard SEN02550-01 Unit: mm Item Criteria Remedy Standard size Standard clearance Clearance limit Clearance between rotor and Replace shaft 0.056 – 0.105 0.111 PC138US, USLC-8...
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SEN02550-01 10 Structure, function and maintenance standard Blade specification (if equipped) From control valve (R.H. travel REVERSE) To R.H. travel motor port A From control valve (L.H. travel FORWARD) To L.H. travel motor port A From control valve (R.H. travel FORWARD) To R.H.
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10 Structure, function and maintenance standard SEN02550-01 Unit: mm Item Criteria Remedy Standard size Standard clearance Clearance limit clearance between rotor and Replace shaft 0.056 – 0.105 0.111 PC138US, USLC-8...
SEN02550-01 10 Structure, function and maintenance standard Solenoid valve PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02550-01 : From self pressure reducing valve Operation : To PPC valve : To center swivel joint, port E1 Check valve : To swing motor, port B : To control valve, port PS : To control valve, port PST : To hydraulic tank ACC : To accumulator (for PPC circuit) PPC lock solenoid valve...
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SEN02550-01 10 Structure, function and maintenance standard Solenoid valve When solenoid valve is “de-energized“ (circuit When solenoid valve is “energized“ (circuit is is closed) connected) Coil (1) is de-energized when no signal current Coil (1) is energized when signal current is is supplied to coil (1).
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10 Structure, function and maintenance standard SEN02550-01 PC138US, USLC-8...
SEN02550-01 10 Structure, function and maintenance standard PPC accumulator For PPC circuit Gas plug Shell Poppet Holder Bladder Oil port Outline Mounted on the solenoid valve. If the engine is stopped with the work equipment is kept at an elevated position, the pilot pressure is supplied to the control valve by the pressure of the com- pressed nitrogen gas in the accumulator.
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10 Structure, function and maintenance standard SEN02550-01 For breaker (Machine ready for attachment) For high pressure For low pressure Core Core Locknut Guard rubber Gas port Ring Bladder Shell Bladder Shell Outline Outline Connected to the attachment piping. When the Connected to the attachment piping.
SEN02550-01 10 Structure, function and maintenance standard Holding valve (For boom and arm) PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02550-01 CY : To work equipment cylinder PCY: For pressure pickup port and equalizer circuit : From PPC valve : To tank : From control valve Pilot spool Safety valve Check valve Unit: mm Check item Criteria Remedy...
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SEN02550-01 10 Structure, function and maintenance standard Function Prevents the pressurized oil from reversing from the work equipment cylinder in order to prevents sudden drift of the work equipment at breaking of the piping between the control valve and the work equipment cylinder. Operation When the work equipment lever is in neu- tral...
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10 Structure, function and maintenance standard SEN02550-01 When pressurized oil flows from the main valve to the cylinder When the piping is free of breakage Pressurized oil led to chamber (a) from the control valve becomes higher than the com- bined force of pressure from work equipment cylinder circuit chamber (b) and spring (6).
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SEN02550-01 10 Structure, function and maintenance standard When returning pressurized oil to the main valve from the work equipment cylinder When the piping is free of burst If the piping is bursted Holding pressure of the work equipment cylin- If piping (A) bursts between the control valve der is led to chamber (b) and check valve (5) and the work equipment cylinder.
10 Structure, function and maintenance standard SEN02550-01 Multi-control valve (if equipped) (1) JIS pattern (2) Backhoe pattern Control pattern switching diagram (Port names correspond to the marks on the above figures.) PC138US, USLC-8...
SEN02551-00 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Work equipment Work equipment .............................. 2 Dimensions of components..........................4 Hydraulic cylinder............................8 PC138US, USLC-8...
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SEN02551-00 10 Structure, function and maintenance standard Work equipment Unit: mm Item Criteria Remedy Tolerance Standard Standard Clearance Clearance between mounting size clearance limit Shaft Hole pin and bushing of boom and -0.030 +0.143 0.093 – revolving frame -0.100 +0.063 0.245 Clearance between mounting -0.030...
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10 Structure, function and maintenance standard SEN02551-00 PC138US, USLC-8...
SEN02551-00 10 Structure, function and maintenance standard Dimensions of components PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02551-00 Unit: mm PC138US-8, PC138USLC-8 Tolerance Measurement point Standard size Shaft Hole -0.030 +0.100 — -0.100 +1.0 Arm side 81.5 Cylinder head side ±1.2 +0.5 Boom side -0.2 Arm side -0.7 -0.030 +0.100 — -0.100 —...
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SEN02551-00 10 Structure, function and maintenance standard Bucket PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02551-00 Unit: mm PC138US-8, PC138USLC-8 Measurement point Standard size Tolerance — 371.3 ±0.5 — 51.6 ±0.5 — 97.9° — — 374.9 — — 1,226.6 — — 190.2 — — 5° — — 0° — +0.2 —...
SEN02551-00 10 Structure, function and maintenance standard Hydraulic cylinder Boom cylinder Arm cylinder Bucket cylinder PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02551-00 Blade cylinder Unit: mm Item Criteria Remedy Tolerance Cylinder Standard Standard Clearance name size clearance limit Shaft Hole -0.030 +0.259 0.093 – Boom 0.435 -0.076 +0.063 0.335 Clearance between -0.030 +0.279 0.095 – piston rod and bush- 0.455 -0.076...
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SEN02552-01 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Cab and its attachments Air conditioner ..............................2 PC138US, USLC-8...
SEN02552-01 10 Structure, function and maintenance standard Air conditioner Air conditioner piping diagram PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02552-01 Front warm/cool air outlet Dual pressure switch Rear warm/cool air outlet If abnormally low or high pressure was gener- C: Foot warm/cool air outlet ated in the refrigerant circulation circuit, this D: Defroster warm/cool air outlet switch releases the magnet clutch of the com- Internal air flow outlet pressor to protect a series of cooler-related...
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SEN02552-01 10 Structure, function and maintenance standard Engine Compressor Condenser 3a. Receiver Sight glass Air conditioner unit Dual pressure switch Table of tightening torque for refrigerant piping adapter Unit: Nm{kgm} Item Criteria Remedy Compressor refrigerant piping 7.85 – 11.8 {0.8 – 1.2} lock bolt (Screw size: M6 ×...
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10 Structure, function and maintenance standard SEN02552-01 PC138US, USLC-8...
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SEN02552-01 10 Structure, function and maintenance standard Air conditioner unit PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02552-01 From condenser Outline To compressor The horizontal air conditioner unit on which C: Hot water inlet evaporator (1) and heater core (2) is arranged D: Hot water outlet in parallel. Blower motor (4) is driven to to gen- erate cool and hot air.
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SEN02552-01 10 Structure, function and maintenance standard Functions of major components Internal/external air changeover damper actua- Evaporator Evaporator fin is cooled by the low-pressure, It starts the built-in motor upon receipt of a sig- low-temperature refrigerant gas being sent nal current from the air conditioner controller in from the expansion valve.
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10 Structure, function and maintenance standard SEN02552-01 Air conditioner controller Input and output signals AMP040-36P Input and Input and Signal name output sig- Signal name output sig- nals nals Input/ — CAN_H output Air mix dumper actuator potentiom- Input/ Input CAN_L eter signal output...
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SEN02552-01 10 Structure, function and maintenance standard Compressor From air conditioner unit Function To condenser Other than circulating the refrigerant, it com- presses the refrigerant gas from the evapora- tor to high-pressure, high-temperature misty refrigerant so that it may be easily regenerated (liquefied) at normal temperature.
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10 Structure, function and maintenance standard SEN02552-01 Condenser From compressor Specifications To air conditioner unit Fine pitch (mm) Core Total heat dissipation surface 3.58 Receiver (m²) Max. pressure used 3.53 {36} Function (MPa{kg/cm²}) It cools and liquefies the high-pressure and Weight of desiccating agent high-temperature misty refrigerant from the compressor.
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SEN02552-01 10 Structure, function and maintenance standard Sensor External air temperature sensor Sunlight sensor Outline The external air temperature sensor is installed Outline in the battery room at the rear left of the The sunlight sensor is installed on top of the machine.
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10 Structure, function and maintenance standard SEN02552-01 PC138US, USLC-8...
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SEN02553-01 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 10 Structure, function and maintenance standard Electrical system Electronic control system ..........................2 Monitor system.............................. 35 KOMTRAX system............................49 Sensor................................51 PC138US, USLC-8...
SEN02553-01 10 Structure, function and maintenance standard Electronic control system Machine control system diagram PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02553-01 PC138US, USLC-8...
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SEN02553-01 10 Structure, function and maintenance standard Engine control function Battery Function Battery relay The neutral safety circuit is employed to Fusible link secure safety when the engine is started. Fuse box The engine does not start until the lock Starting switch lever is set in the “LOCK“...
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10 Structure, function and maintenance standard SEN02553-01 Starting engine When starting switch (5) is turned “ON“, engine controller (6) sends command current to fuel supply pump (14). For this reason, a fail-safe mechanism is pro- vided with the electrical system to stop the engine when an electrical failure occurs.
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SEN02553-01 10 Structure, function and maintenance standard Pump and engine mutual control function Battery Input and output signals Battery relay Constant power supply Fusible link CAN signal Fuse box PC-EPC valve drive signal Resistor Solenoid valve GND Pump controller Oil pressure sensor signal Engine controller Oil pressure switch signal Machine monitor...
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10 Structure, function and maintenance standard SEN02553-01 Function A function that selects working mode with the working mode selector switch in the machine monitor. 5 modes (P, E, L, ATT, B) are avail- able, allowing the operator to select appropri- ate engine torque (T) and pump absorption torque depending on the work.
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SEN02553-01 10 Structure, function and maintenance standard Control method in each mode P mode, E mode, and ATT mode Matching point: Working mode Matching point 68.4 kW/2,200 rpm Travel {91.7 HP/2,200 rpm} Working 64.4 kW/2,050 rpm P, ATT (At arm digging) {86.4 HP/2,050 rpm} Working 66.3 kW/2,050 rpm...
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10 Structure, function and maintenance standard SEN02553-01 Modes B and L Working mode Partial output Matching point: Working mode Matching point 50.9 kW/1,870 rpm {68.2 HP/1,870 rpm} 47.8 kW/1,640 rpm {64.1 HP/1,640 rpm} In B or L mode, engine output is controlled to a constant level.
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SEN02553-01 10 Structure, function and maintenance standard Control function during travel Control function with emergency pump drive Traveling the machine in P or ATT mode switch “ON“ increases engine speed (N). If the controller gets out of order and no work is Traveling the machine in E, L or B mode does possible because the hydraulic pump does not not change engine speed (N) or pump absorp-...
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10 Structure, function and maintenance standard SEN02553-01 PC138US, USLC-8...
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SEN02553-01 10 Structure, function and maintenance standard Auto-decelerator function Pump controller Input and output signals Engine controller CAN signal Machine monitor Oil pressure sensor signal Fuel control dial Oil pressure switch signal Fuel supply pump Throttle signal Sensors Fuel supply pump control signal Oil pressure sensor Sensor signals Oil pressure switch...
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10 Structure, function and maintenance standard SEN02553-01 Function When all the control levers are set to NEU- TRAL for waiting for a dump track or work, the engine speed is automatically reduced to a control speed, and fuel consumption and noise are lowered.
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SEN02553-01 10 Structure, function and maintenance standard Engine automatic warm-up function Battery Input and output signals Battery relay CAN signal Fusible link PC-EPC valve drive signal Fuse box Solenoid valve GND Resistor Hydraulic oil temperature signal Pump controller Throttle signal Engine controller Fuel supply pump control signal Machine monitor...
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10 Structure, function and maintenance standard SEN02553-01 Function Raises the engine speed automatically to warm up the engine if the coolant temperature is low after start-up of the engine. Operational conditions (all required) Operation Coolant temperature: Max. 30°C Engine speed: 1,300 rpm Fuel control dial: Max.
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SEN02553-01 10 Structure, function and maintenance standard Turbocharger protection function a See “Engine automatic warm-up function“ for system circuit diagram. When the engine is started at low temperatures and the engine speed is increased sharply, the turbo- charger may be seized. Controlling the engine speed prevents this problem. Duration of engine speed control depends on the coolant temperature.
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10 Structure, function and maintenance standard SEN02553-01 Swing control function Battery Input and output signals Battery relay Swing holding brake release signal Fusible link Swing holding brake solenoid valve drive sig- Fuse box Swing holding brake release switch CAN signal Swing lock switch Solenoid valve GND Pump controller...
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SEN02553-01 10 Structure, function and maintenance standard Function Swing lock switch Swing lock and swing holding brake functions Swing lock Turning swing lock switch (1) to “ON“ locks the monitor swing lock (manual lock) at any position. Function Swing holding brake Swing lock Interlocked with the swing operation, the swing •...
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10 Structure, function and maintenance standard SEN02553-01 Swing holding brake release function If the controller gets out of order and no swing is possible because the swing holding brake does not work properly, operating swing hold- ing brake release switch (2) releases the swing holding brake and allows swing operation.
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SEN02553-01 10 Structure, function and maintenance standard Travel control function Pump controller Input and output signals Engine controller Oil pressure sensor signal Machine monitor CAN signal Fuel control dial Pump merge-divider solenoid valve drive sig- Fuel supply pump Sensors Travel junction solenoid valve drive signal Pump oil pressure sensor 2nd travel speed select solenoid valve drive Oil pressure sensor...
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10 Structure, function and maintenance standard SEN02553-01 Function Travel speed select function Travel speed “Manual“ change Turning the travel speed selector switch “Hi“ and “Lo“ changes the motor capacity and allows the machine to select travel speed. Lo (low Hi (high Travel speed selector switch speed) speed)
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SEN02553-01 10 Structure, function and maintenance standard Pump merge-divider function When the travel lever is operated, detects the pilot pressure and judges if it is for straight-travel. For straight-travel, a signal is sent to the pump merge-divider solenoid valve, dividing the pump delivery, to improve travel performance.
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10 Structure, function and maintenance standard SEN02553-01 PPC lock function Battery Function Battery relay Interlocked with the lock lever, the PPC lock Fusible link switch is turned “OFF“ when operating the lock Fuse box lever to “LOCK“ position. Starting switch When the PPC lock switch is turned “OFF“, the Lock lever current to the PPC lock solenoid valve is cut-...
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SEN02553-01 10 Structure, function and maintenance standard Oil flow adjuster function for attachment (Machine ready for attachment) Pump controller Input and output signals Engine controller Oil flow adjuster EPC valve drive signal for Machine monitor attachment Fuel control dial Oil pressure switch signal Fuel supply pump CAN signal Sensors...
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10 Structure, function and maintenance standard SEN02553-01 PC138US, USLC-8...
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SEN02553-01 10 Structure, function and maintenance standard System components Engine controller Input and output signals The following is the list of the symbols used for signal classification in the input/output signal chart. A: Power supply B: Input C: Ground/shield/return D: Output E: Communication DTP-4P [CN-CE03] Signal...
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10 Structure, function and maintenance standard SEN02553-01 DRC-60P(1) [CN-CE01] Signal Signal Pin No. Signal name Pin No. Signal name classification classification — — — Engine oil pressure switch — — — — — — — Sensor power supply (5 V) —...
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SEN02553-01 10 Structure, function and maintenance standard Pump controller PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02553-01 Input and output signals AMP-81P [CN-C01] Input/output Input/output Pin No. Signal name Pin No. Signal name signal signal Constant power supply (24 V) Input — Input — Window washer Output Starting switch ACC signal Input Constant power supply (24 V) Input...
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SEN02553-01 10 Structure, function and maintenance standard Fuel control dial Knob Dial Spring Ball Potentiometer Connector Function Installed in the right console box. Potentiome- ter (5) is installed inside knob (1). Turning knob (1) causes potentiometer (5) shaft to rotate. This rotation changes the resistance of the variable resistor within potentiometer (5), and a throttle signal is sent to the controller.
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10 Structure, function and maintenance standard SEN02553-01 Resistor Resistance Connector Specifications For PC-EPC valve: 30 Function Sends an electric current to each EPC valve that is appropriate for each condition, when the emergency pump drive switch is turned to “ON“. a No electric current flows in the normal condi- tion.
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SEN02553-01 10 Structure, function and maintenance standard Engine oil pressure switch Connector Sensor O-ring Specifications Contact type: Normal close Function Installed in the cylinder block. Detects engine oil pressure, and turns the switch “ON“ when the pressure goes below the specified value. PC138US, USLC-8...
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10 Structure, function and maintenance standard SEN02553-01 PPC oil pressure switch Plug Switch Connector Specifications Contact type: Normal open Operating pressure to make contact point ON: 490 ± 98.1 kPa {5.0 ± 1.0 kg/cm Operating pressure to break contact point OFF: 294 ±...
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SEN02553-01 10 Structure, function and maintenance standard PC138US, USLC-8...
10 Structure, function and maintenance standard SEN02553-01 Monitor system Machine monitor Outline Battery The monitor system keeps the operator Pump controller informed of all machine functions, by monitor- Engine controller ing the machine conditions using the sensors Air conditioner controller and switches installed in various parts of the KOMTRAX terminal machine and processing them instantly to dis-...
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SEN02553-01 10 Structure, function and maintenance standard Machine monitor Outline Precautions on the machine monitor display The machine monitor provides monitor display The LCD panel may have black points (points function, mode selection function and switch which are not lighted) and bright points (points function of the electrical equipment etc.
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10 Structure, function and maintenance standard SEN02553-01 Input and output signals 070-18P(1) [CN-CM01] Input/output Input/output Pin No. Signal name Pin No. Signal name signal signal Constant power supply (24 V) Input Engine coolant temperature Input Constant power supply (24 V) Input Battery level Input...
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SEN02553-01 10 Structure, function and maintenance standard Display Normal operation screen All indicators light-up screen When monitor items (14) to (16) are faulty after starting the engine, monitor items are displayed on the screen in chronological order from the upper left. If the hydraulic oil temperature goes High or Low while the hydraulic oil temperature gauge is dis- played at the center of the screen, the screen displays only hydraulic oil temperature monitor (2b).
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10 Structure, function and maintenance standard SEN02553-01 No. Classification Display item Description Remarks Display Tempera- Background location ture (°C) color • Indicates corresponding temperature range. (*1) Gauge • Alarm buzzer sounds when the temper- Blue Coolant tem- ature exceeds 105°C. perature Blue •...
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SEN02553-01 10 Structure, function and maintenance standard No. Classification Display item Description Remarks Elapsed time after turning Monitor dis- the starting switch to play “HEAT (preheat)“. Preheat • Indicates preheat operating status. 0 – 30 sec. 30 – 40 sec. Blink 40 sec.
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10 Structure, function and maintenance standard SEN02553-01 PC138US, USLC-8...
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SEN02553-01 10 Structure, function and maintenance standard Switches Name Function Operation Turns the auto-decelerator function ON/ • When the working mode is in “L“, the auto- Auto-decelerator OFF. decelerator does not work. switch Light ON: ON [Numeric keypad: 1] OFF i o ON Light OFF: OFF Heavy-duty operation (*1) Working mode...
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10 Structure, function and maintenance standard SEN02553-01 Name Function Operation • The air flow increases immediately after Fan switch (Up) the air conditioner adjustment screen Controls the fan speed of the air condi- [Numeric keypad: 7] appears. tioner in 6 levels. (Low, Medium 1, Medium 2, Medium 3, •...
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SEN02553-01 10 Structure, function and maintenance standard Guidance icon and function switch Functions available with the function switch depend on the guidance icon displayed above the switch. No function is available if no guidance icon appears above the function switch. The following is the list of guidance icons and the functions displayed above the function switches.
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10 Structure, function and maintenance standard SEN02553-01 Guidance Function switch Item Function icon Selecting maintenance screen Selects maintenance screen. Return Returns to the previous screen or condition. Selecting user mode screen Selects user mode screen. Fixes selected/displayed item. PC138US, USLC-8...
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Display and setting of some functions require special operation of the switch. Items available in the operator mode are as follows: Display order (*2) Category Item (*1) Display of KOMATSU logo Display of inputting password — — — Display of start-up check Display of warning after start-up check —...
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10 Structure, function and maintenance standard SEN02553-01 Oil flow setting for breaker Oil flow setting for attachment Oil flow for the breaker can be changed in the Oil flow for the compound attachment can be “Breaker/attachment setting“ of the user mode. changed in the “Breaker/attachment setting“...
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SEN02553-01 10 Structure, function and maintenance standard Service mode function The functions in this mode are not accessible from the normal operation screen. Display and setting of these functions are available by the serviceman's special operations of the switch. This mode is used for special setting, testing, adjusting or troubleshooting. Items available in the service mode are as follows: Monitoring Mechanical systems...
10 Structure, function and maintenance standard SEN02553-01 KOMTRAX system The KOMTRAX system consists of the KOMTRAX terminal, communication antenna, machine monitor and GPS antenna. This system sends various information of the machine via wireless communication. It allows operators of the KOMTRAX to obtain the machine information from the office and to pro- vide various services with the customers.
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SEN02553-01 10 Structure, function and maintenance standard KOMTRAX terminal TH300 The KOMTRAX system uses satellite commu- Input and output signals nication technology. AMP-14P [CN-CK01] Communication antenna connection Input/output Pin No. Signal name signal Machine harness connection (AMP-14P) Machine harness connection (AMP-10P) Power supply (5 V) Input —...
10 Structure, function and maintenance standard SEN02553-01 Sensor Atmospheric pressure sensor Connector Pressure inlet port Function Installed in the bracket on the side face of the cylinder block. Detects the ambient pressure and outputs variable voltage. Boost pressure, temperature sensor Connector Sensor O-ring...
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SEN02553-01 10 Structure, function and maintenance standard Coolant temperature sensor Connector Sensor O-ring Function Installed in the water pump. Detects the temperature change and outputs signal as a resistance change. Crankshaft speed sensor Camshaft speed sensor Connector Sensor O-ring Function The crankshaft speed sensor is installed in the gear of the flywheel, and the camshaft speed sensor is installed in the gear of the camshaft.
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10 Structure, function and maintenance standard SEN02553-01 Common rail pressure sensor Common rail Sensor Connector Function Installed in the common rail. Detects the fuel pressure and outputs variable voltage. Engine oil level sensor Connector Float Bracket Switch Function The engine oil level sensor is installed to the side of the oil pan. If the oil level lowers below the specified level, the float lowers and the switch is turned “OFF“.
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SEN02553-01 10 Structure, function and maintenance standard Fuel level sensor Connector Spring Float Contact Spacer Body Function This sensor is installed on the side face of the fuel tank. The float moves up and down according to the fuel level. The float moves the variable resistor through the arm.
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10 Structure, function and maintenance standard SEN02553-01 Hydraulic oil temperature sensor Connector Plug Thermistor Function Installed in the suction pipe of the hydraulic pump. Detects the temperature change and outputs signal as a resistance change of the thermistor. Pump oil pressure sensor O-ring Output characteristics Sensor...
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SEN02553-01 10 Structure, function and maintenance standard PPC oil pressure sensor (For travel and blade operation) O-ring Output characteristics Sensor Connector Function The PPC oil pressure sensor is installed in the control valve connecting part of the pilot circuit for travel and blade operation. Detects the pilot pressure and outputs variable voltage.
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10 Structure, function and maintenance standard SEN02553-01 PC138US, USLC-8...
SEN02457-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 20 Standard value table Standard service value table Standard value table for engine related parts ....................2 Standard value table for chassis related parts ....................3 PC138US, USLC-8...
SEN02457-01 20 Standard value table Standard value table for engine related parts Applicable model PC138US-8 Engine SAA4D95LE-5 Standard value for Cate- Item Test conditions Unit Service limit value gory new machine High idle 2,300 ± 60 — • Coolant Low idle 1,100 ±...
20 Standard value table SEN02457-01 Standard value table for chassis related parts Applicable model PC138US-8 Standard value for Cate- Item Test conditions Unit Service limit value gory new machine • Hydraulic oil temperature: 45 – 55°C • Engine oil pressure: At 1-pump relief 2,050 ±...
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SEN02457-01 20 Standard value table Applicable model PC138US-8 Standard value for Cate- Item Test conditions Unit Service limit value gory new machine +1.5 • Hydraulic oil temperature: 27.1 ± 1.0 27.1 –2.5 Swing relief 45 – 55°C {276 ± 10} {276 –25 •...
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20 Standard value table SEN02457-01 Applicable model PC138US-8 Standard value for Cate- Item Test conditions Unit Service limit value gory new machine • For testing posture, see Swing • Engine stopped • Hydraulic oil temperature: 45 – 55°C • Bucket at rated load (450 kg) Hydraulic drift of Deg.
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SEN02457-01 20 Standard value table Applicable model PC138US-8 Standard value for Cate- Item Test conditions Unit Service limit value gory new machine • Engine at high idle • Hydraulic oil temperature: Leakage from travel l/min 45 – 55°C Max. 1.1 Max.
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20 Standard value table SEN02457-01 Applicable model PC138US-8 Standard value for Cate- Item Test conditions Unit Service limit value gory new machine • For testing posture, see Work equipment 6 • Engine at low idle • Hydraulic oil temperature: 45 – 55°C Boom •...
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SEN02457-01 20 Standard value table Pump performance curve TVC current: 0.4 A Pump speed: At 2,400 rpm (Engine rated speed at 1,800 rpm) Test pump Discharge Average Standard value for Judgement discharge pressure of Check point pressure discharge amount standard lower pressure other pump Q (l/min)
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20 Standard value table SEN02457-01 Posture of machine for testing performance and Travel 2: Travel speed (actual run), travel deviation test procedure Swing 1: Swing brake angle, time taken to start swing, time taken to swing Travel 3: Travel deviation Swing 2: Hydraulic drift of swing Travel 4: Hydraulic drift of travel Travel 1: Travel speed (without load)
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SEN02457-01 20 Standard value table Work equipment 1: Hydraulic drift of work Work equipment 4: Bucket speed equipment Work equipment 5: Blade speed Work equipment 2: Boom speed Work equipment 6: Boom time lag Work equipment 3: Arm speed PC138US, USLC-8...
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20 Standard value table SEN02457-01 Work equipment 7: Arm time lag Work equipment 8: Bucket time lag Work equipment 9: Blade time lag PC138US, USLC-8...
SEN02458-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 30 Testing and adjusting Testing and adjusting, Part 1 Tools for testing, adjusting, and troubleshooting..................... 3 Testing engine speed ............................6 Testing exhaust temperature...........................
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SEN02458-01 30 Testing and adjusting Checking and adjusting air conditioner compressor belt tension ..............24 Checking and adjusting track shoe tension....................25 Testing and adjusting oil pressure in work equipment, swing, and travel circuits ......... 27 Testing control circuit basic pressure ......................30 Testing and adjusting oil pressure in pump PC control circuit...............
30 Testing and adjusting SEN02458-01 Tools for testing, adjusting, and troubleshooting Sym- Testing/Adjusting item Part No. Part name Remarks Exhaust temperatures 799-101-1502 Digital thermometer 1 -99.9 – 1,299°C 1 799-201-9001 Handy smoke checker 1 Bosch index: 0 – 9 Checking exhaust gas Commercially color Smoke meter...
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SEN02458-01 30 Testing and adjusting Sym- Testing/Adjusting item Part No. Part name Remarks Pressure gauge: 2.5, 5.9, 39.2, 58.8 MPa 799-101-5002 Hydraulic tester {25, 60, 400, 600 kg/cm Testing basic pressure of Pressure gauge: 58.8 MPa 790-261-1204 Digital hydraulic tester control circuit {600 kg/cm 799-101-5220 Nipple...
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30 Testing and adjusting SEN02458-01 Sym- Testing/Adjusting item Part No. Part name Remarks 799-601-4100 799-601-4200 T-adapter assembly 799-601-9000 799-601-9200 799-601-9020 • Adapter for DT 1 For DT2P For DT3P (Does not include 799-601- 799-601-9030 • Adapter for DT 4100 and 799-601-4200) For DT6P (Does not include 799-601- 799-601-9050 •...
SEN02458-01 30 Testing and adjusting Testing engine speed Testing pump relief speed Start the engine and operate the arm cyl- a Test the engine speed with the monitoring inder to the IN stroke end. function of the machine monitor. Set the fuel control dial in the high idle a Test the engine speed under the following con- (MAX) position and set the working mode dition.
30 Testing and adjusting SEN02458-01 Testing exhaust temperature Run the engine and test the exhaust tempera- ture over the speed range. a Testing tools for exhaust temperature Symbol Part No. Part name 799-101-1502 Digital thermometer Install or remove the testing instrument after the exhaust manifold temperature has lowered.
SEN02458-01 30 Testing and adjusting Checking exhaust gas color a Checking tools for exhaust gas color Symbol Part No. Part name 799-210-9001 Handy smoke checker Commercially Smoke meter available Stop the machine on a level ground and lower the work equipment to the ground. Be careful not to touch any hot part when removing or installing the checking tools.
30 Testing and adjusting SEN02458-01 Adjusting valve clearance Remove plate (5) on the starting motor and insert gear B1. a Adjusting tools for valve clearance Symbol Part No. Part name 795-799-1131 Gear Commercially Thickness gauge available Stop the machine on a level ground and lower the work equipment to the ground.
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SEN02458-01 30 Testing and adjusting Adjust the valve clearances marked with q in After finishing adjustment, remove the adjust- the valve arrangement drawing according to ing tools and return the removed parts. the following procedure. Take care not to forget remove gear B1. Cylinder head cover mounting nut: 8.82 ±...
30 Testing and adjusting SEN02458-01 Testing compression pressure a Testing tools for compression pressure Symbol Part No. Part name 795-502-1590 Compression gauge 795-471-1420 Adapter 6261-11-3880 Gasket When testing the compression pressure, take care n ot to burn yourself on t he exhaust manifold or muffler or get caught in a rotating part.
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SEN02458-01 30 Testing and adjusting Disconnect CE03 connector (5) of the engine controller. If the connector is not disconnected, the engine may starts during test and that is dangerous. Accordingly, be sure to disconnect the connector. Since the CE03 connector is the power supply circuit of the engine controller, cover the connector on the machine side with a vinyl sheet etc.
30 Testing and adjusting SEN02458-01 Testing blow-by pressure a Testing tools for blow-by pressure Symbol Part No. Part name 799-201-1504 Blow-by checker Stop the machine on a level ground and lower the work equipment to the ground. a Test the blow-by pressure under the following condition.
SEN02458-01 30 Testing and adjusting Testing engine oil pressure a Testing tools for engine oil pressure Symbol Part No. Part name 799-101-5002 Hydraulic tester 790-261-1204 Digital hydraulic tester 799-401-2320 Gauge Stop the machine on a level ground and lower the work equipment to the ground. a Test the engine oil pressure under the follow- ing condition.
30 seconds after the engine is a Precautions for replacing fuel filter cartridge stopped. Be sure to use the Komatsu genuine fuel filter a Before the fuel circuit is checked and its parts cartridge. are removed, the residual pressure in the fuel Since the common rail fuel injection system circuit must be released completely.
SEN02458-01 30 Testing and adjusting Testing fuel pressure a Testing tools for fuel pressure Symbol Part No. Part name 799-101-5002 Hydraulic tester 790-261-1204 Digital hydraulic tester 795-471-1450 Adapter (8 x 1.25 mm) 07005-00812 O-ring 799-401-2320 Gauge Stop the machine on a level ground and lower the work equipment to the ground.
30 Testing and adjusting SEN02458-01 a Lay test hose G4 so that it will not Testing fuel return rate and fuel slacken and put its end in the oil pan. leakage a Testing tools for fuel return rate and fuel leak- Symbol Part No.
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SEN02458-01 30 Testing and adjusting Testing return rate from injector Testing leakage from pressure limiter a While testing the return rate from the Lay test hose G4 so that it will not slacken injector, keep the test hose on the pres- and put its end in the oil pan.
30 Testing and adjusting SEN02458-01 Bleeding air from fuel circuit a If fuel is used up or if a fuel circuit part is removed and installed, bleed air from the fuel circuit according to the following procedure. Stop the machine on a level ground and lower the work equipment to the ground.
Page 348
SEN02458-01 30 Testing and adjusting a Air bleeding route of fuel circuit Fuel tank o Pre-filter o Main filter o Feed pump o Metering unit o Fuel tank Fuel tank Priming pump Pre-filter with water separator Main filter Feed pump IMV (Inlet Metering Valve) Overflow valve Rail...
30 Testing and adjusting SEN02458-01 Checking fuel circuit for leakage Check the fuel piping and devices for fuel leak- age. Very high pressure is generated in the high- a Check mainly around the high-pressure pressure circuit of the fuel system. If fuel circuit parts coated with the color checker leaks while the engine is running, it is dan- for fuel leakage.
SEN02458-01 30 Testing and adjusting Testing and adjusting alternator Adjusting belt tension a If the deflection is out of the standard range, adjust the belt tension according to the follow- Testing ing procedure. Remove the engine compartment side cover and air intake pipe (1). Loosen alternator fixing bolts (1) and (2).
30 Testing and adjusting SEN02458-01 Testing swing circle bearing Set the arm almost perpendicular to the ground and lower the boom until the front track clearance shoe floats. a Testing tools for swing circle bearing clearance a At this time the front of the upper structure rises and the rear lowers.
SEN02458-01 30 Testing and adjusting Checking and adjusting air Adjusting conditioner compressor belt a If the belt deflection is abnormal, adjust it according to the following procedure. tension Stop the machine on a level ground and Loosen bolts (1) and (2) and locknut (6). lower the work equipment to the ground.
30 Testing and adjusting SEN02458-01 Checking and adjusting track Adjusting shoe tension a If the track shoe tension is abnormal, adjust it according to the following procedure. Checking Run the engine at low idle and drive the Increasing tension machine forward by the length of track on Add grease through grease fitting (2) with ground, and then stop slowly.
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SEN02458-01 30 Testing and adjusting Decreasing tension Loosen valve (1) to discharge grease, and then tighten it. Do not loosen the valve more than 1 turn. If it is loosened more, it may jump out because of the high- pressure grease in it. To check that the tension is normal, run the engine at low idle and move the machine forward by the length of track on...
30 Testing and adjusting SEN02458-01 Testing and adjusting oil pressure in work equipment, swing, and travel circuits a Testing and adjusting tools for oil pressure in work equipment, swing, and travel circuits Symbol Part No. Part name 799-101-5002 Hydraulic tester 790-261-1204 Digital hydraulic tester 799-101-5220 Nipple (10 ×...
Page 356
SEN02458-01 30 Testing and adjusting Testing work equipment relief pressure Set the working mode in the power mode Start the engine and move the cylinder to (P). be tested to the stroke end. Run the engine at high idle, operate the Set the working mode in the power mode travel lever and pedal to relieve the travel (P).
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30 Testing and adjusting SEN02458-01 Adjusting Adjusting swing relief pressure a If the swing relief pressure is abnormal, a The unload valve and safety-suction valve for adjust safety valve (6) of the swing motor lowering the boom cannot be adjusted. according to the following procedure.
SEN02458-01 30 Testing and adjusting Testing control circuit basic Start the engine, set the working mode in the power mode (P), and turn the auto-decelerator pressure OFF. a Testing tools for control circuit basic pressure Run the engine at high idle, set all the levers Symbol Part No.
30 Testing and adjusting SEN02458-01 Testing and adjusting oil pressure in pump PC control circuit a Testing and adjusting tools for oil pressure in pump PC control circuit Symbol Part No. Part name 799-101-5002 Hydraulic tester 790-261-1204 Digital hydraulic tester 799-101-5220 Nipple (10 ×...
Page 360
SEN02458-01 30 Testing and adjusting Run the engine at high idle, operate the Install nipples L2 and connect them to oil left work equipment control lever to relieve pressure gauges [1]. a Use the oil pressure gauges of 5.9 the arm circuit at the IN stroke end, and test the oil pressure.
Page 361
30 Testing and adjusting SEN02458-01 Adjusting Adjusting pump PC valve a If the following phenomenon occurs and PC valve (4) seems to be defective, adjust PC valve (4) according to the following procedure. As the working load increases, the engine speed lowers remarkably.
SEN02458-01 30 Testing and adjusting Testing and adjusting oil pressure in pump LS control circuit a Testing and adjusting tools for oil pressure in pump LS control circuit Symbol Part No. Part name 799-101-5002 Hydraulic tester 790-261-1204 Digital hydraulic tester 799-401-2701 Differential pressure gauge 799-101-5220 Nipple (10 ×...
Page 363
30 Testing and adjusting SEN02458-01 Set the working mode in the power mode Open the side cover of the pump room (P) and set the travel speed in the High and remove oil pressure pickup plugs (1) position. and (2). Run the engine at high idle, set all the (1): Pump discharge pressure pickup levers and pedals for work equipment con-...
Page 364
SEN02458-01 30 Testing and adjusting a Testing condition and method of judg- The figure shows the LS pressure side. ment: If the pressures are in the fol- lowing ratio, the LS valve is normal. LS differential Operation of levers pressure 2.8 ±...
Page 365
30 Testing and adjusting SEN02458-01 Adjusting Adjusting LS valve a If the LS differential pressure is abnormal, adjust the LS valve according to the following procedure. (3): Pump LS valve While fixing adjustment screw (4), loosen lock- nut (5). Turn adjustment screw (4) to adjust the differ- ential pressure.
SEN02458-01 30 Testing and adjusting Testing solenoid valve output Install adapter N2 and connect the discon- nected hose again. pressure a Testing tools for solenoid valve output pressure Install nipple [1] of hydraulic tester N1 and con- nect it to oil pressure gauge [2]. Symbol Part No.
30 Testing and adjusting SEN02458-01 a Testing tools for PPC valve output pressure Testing PPC valve output pressure Symbol Part No. Part name Connecting points of PPC piping 799-101-5002 Hydraulic tester 790-261-1204 Digital hydraulic tester 799-401-3100 Adapter (Size: 02) Stop the machine on a level ground and lower the work equipment to the ground.
Page 368
SEN02458-01 30 Testing and adjusting Start the engine and set the working mode in the power mode (P). Run the engine at high idle and test the oil pressure with the control lever in neutral and moved to the stroke end. a If the output pressure is as follows, the PPC valve is normal.
30 Testing and adjusting SEN02458-01 Adjusting play of work equipment and swing PPC valves a If the right and left work equipment levers have large play, adjust them according to the follow- ing procedure. Remove the work equipment and swing PPC valve assembly.
SEN02458-01 30 Testing and adjusting Checking parts which cause Checking arm cylinder Stop the arm cylinder about 100 mm before hydraulic drift of work equipment1 the IN stroke end and stop the engine. a If the work equipment (cylinder) drifts hydrauli- cally, check to see if the cause is on the cylin- d e r pa c k i n g s i d e o r c o n t r o l v a l v e s i d e according to the following procedure.
Page 371
30 Testing and adjusting SEN02458-01 Checking PPC valve While the pressure in the accumulator is high, set the lock lever in the LOCK/FREE position and test the lowering distance. a Operate the control lever while the starting switch is in the ON position. a If the pressure in the accumulator is lost, run the engine for about 5 seconds to heighten the pressure in the accumulator.
SEN02458-01 30 Testing and adjusting Testing and adjusting travel deviation Inspection Run the engine and heighten the hydraulic oil temperature to the operating range and set the machine in the travel posture. a To set the machine in the travel posture, extract the bucket cylinder and arm cylin- der fully and set the boom angle to 45°.
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30 Testing and adjusting SEN02458-01 Adjustment Fixing plug (3) with a hexagonal wrench (Width a If the machine deviates, it can be corrected by across flats: 4 mm), loosen locknut (4). a If the locknut is sealed with a vinyl tape, partially draining the oil discharged more from remove that tape.
SEN02458-01 30 Testing and adjusting Releasing residual pressure from Repeat steps 2) and 3) above 2 – 3 times, and the residual pressure in the piping is hydraulic circuit released completely. Releasing residual pressure from hydraulic tank Releasing residual pressure from swing Since the hydraulic tank is enclosed motor circuit and pressurized, release the residual...
30 Testing and adjusting SEN02458-01 Testing oil leakage Testing oil leakage from arm cylinder Move the arm cylinder to the IN stroke end a Testing tools for oil leakage and stop the engine. Release the residual pressure from Symbol Part No. Part name the piping on the arm cylinder Commercially...
Page 376
SEN02458-01 30 Testing and adjusting Testing oil leakage from bucket cylinder Testing oil leakage from swing motor Move the bucket cylinder to the CURL Disconnect 2 drain hoses (4) and block stroke end and stop the engine. the hose side with plugs. a Use the following parts to block the Release the residual pressure from the piping on the bucket cylinder...
Page 377
30 Testing and adjusting SEN02458-01 Testing oil leakage from travel motor After finishing test, return the removed Remove the travel motor cover. parts. Run the engine, lock the travel mecha- nism, and stop the engine. Put pin [1] between the sprocket and track frame to lock the travel mechanism securely.
SEN02458-01 30 Testing and adjusting Bleeding air from each part Air bleeding procedure Air bleeding item Bleeding air Checking oil Bleeding air Bleeding air from Starting Bleeding air level and from swing from travel hydraulic engine from cylinder starting Contents of work motor motor pump...
Page 379
30 Testing and adjusting SEN02458-01 While running the engine at high idle, per- Checking oil level and starting work form step 2). Run the engine, retract the arm cylinder While running the engine at low idle, move and bucket cylinder to the stroke ends, the piston rod to the stroke end and lower the work equipment to the ground, relieve the oil.
SEN02458-01 30 Testing and adjusting Checking cab tipping stopper Adjusting mirrors Adjusting mirrors (a1) and (b1) Loosen bolts (1) and (2) of the mirrors and adjust the mirrors so that the operator can see the right and left rear views best which are blind corners from the operator's seat.
Page 381
30 Testing and adjusting SEN02458-01 PC138US, USLC-8...
SEN02459-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 30 Testing and adjusting Testing and adjusting, Part 2 Special functions of machine monitor ......................2 PC138US, USLC-8...
SEN02459-00 30 Testing and adjusting Special functions of machine monitor Air conditioner specification PC138US, USLC-8...
Page 385
30 Testing and adjusting SEN02459-00 Upper section of machine monitor (Display sec- tion) (a): Multi-display a When the engine is started, the battery voltage may lower suddenly, depending on the ambi- ent temperature and the condition of the bat- tery. In this case, the machine monitor goes off for a moment.
Page 386
This mode is used for special setting, testing, adjusting, or troubleshooting. Page Page t Operator mode (Outline) Service mode A Display of KOMATSU logo Monitoring A Display of inputting password Mechanical Systems Abnormality A Display of check before starting...
Page 387
30 Testing and adjusting SEN02459-00 a Classification of operator mode A: Display/Function from time when starting switch is turned ON to time when screen changes to ordi- nary screen and display after starting switch is turned OFF B: Display/Function when switch of machine monitor is operated C: Display/Function when certain condition is satisfied D: Display/Function which needs special operation of switch PC138US, USLC-8...
Page 388
KOMATSU logo is displayed for 2 seconds. Display of ending of maintenance — — — — 3 a After the KOMATSU logo is displayed for 2 interval seconds, the screen changes to "Display of Display of check of working mode 4 3 4 4 4 inputting password", or "Display of check...
Page 389
SEN02459-00 Display of inputting password Display of warning after check before starting After the KOMATSU logo is displayed, the screen If any abnormality is detected by the check before to input the engine start lock password is displayed. starting, the warning monitor is displayed on the a This screen is displayed only when the engine screen.
Page 390
SEN02459-00 30 Testing and adjusting Display of check of working mode and travel Display of end screen speed When the starting switch is turned OFF, the end screen is displayed for 5 seconds. If the check before starting is finished normally, the a Another message may be displayed on the screen to check the working mode and travel speed end screen, depending on the message dis-...
Page 391
30 Testing and adjusting SEN02459-00 Selection of working mode When the ordinary screen is displayed again, large working mode monitor (a) is displayed for Select a working mode according to the following 2 seconds, and then the setting of the working procedure.
Page 392
SEN02459-00 30 Testing and adjusting Selection of travel speed Operation of windshield wiper While the ordinary screen is displayed, if the travel While the ordinary screen is displayed, if the wiper speed shifting switch is pressed, large travel speed switch is pressed, large wiper monitor (a) is dis- monitor (a) is displayed for 2 seconds and the set- played for 2 seconds and the windshield wiper ting of the travel speed is changed.
Page 393
30 Testing and adjusting SEN02459-00 Operation of air conditioner/heater Operation to display camera mode While the ordinary screen is displayed, press the air When a camera is installed, if [F3] is pressed, the conditioner switch and the air conditioner adjust- multi-display changes to the camera image (Set the ment screen is displayed.
Page 394
SEN02459-00 30 Testing and adjusting Operation to display clock and service meter Check of maintenance information While the ordinary screen is displayed, press [F4], While the maintenance monitor or ordinary screen and section (a) changes to the service meter and is displayed, press [F5], and the maintenance table clock alternately.
Page 395
30 Testing and adjusting SEN02459-00 Setting and display of user mode [KOMTRAX message] (Including KOMTRAX messages for user) There are 2 types of KOMTRAX message; 1 is for the user and the other is for the service. While the ordinary screen is displayed, press [F6], For user: and the user menu screen is displayed.
Page 396
SEN02459-00 30 Testing and adjusting Display of energy-saving guidance Display of user code and failure code When the machine is set in a certain operating con- If an abnormality which displays a user code and a dition, the energy-saving guidance screen is dis- failure code occurs on the ordinary screen or cam- played automatically to urge the operator to the era mode screen, all the information of the abnor-...
Page 397
30 Testing and adjusting SEN02459-00 a Remedies given by displayed user codes to operator to take (The following table is an excerpt from the Operation and Maintenance Manual) User code Failure mode Action When emergency pump drive switch is at the up (emergency) Pump control system error position, normal operations become possible, but have inspection carried out immediately.
Page 398
SEN02459-00 30 Testing and adjusting Function of checking display of LCD (Liquid Function of checking service meter Crystal Display) To check the service meter while the starting switch is turned OFF, operate the numeral input switches While the ordinary screen is displayed, if the follow- as follows.
Page 399
30 Testing and adjusting SEN02459-00 Function of changing attachment/maintenance After the New password input screen is dis- played, input a new password with the numeral password input switches and confirm it with the function When changing the attachment/maintenance pass- switch. word used for the attachment setting function and a Set a new password of 4 –...
Page 400
SEN02459-00 30 Testing and adjusting If the screen to notify completion of setting is displayed and then the ordinary screen is dis- played, the password is changed successfully. PC138US, USLC-8...
Page 401
30 Testing and adjusting SEN02459-00 a The items which can be selected in the Service mode service menu are as follows (including To change the operator mode to the service mode, some items which need special opera- perform the following operation. tions).
Page 402
SEN02459-00 30 Testing and adjusting Monitoring The machine monitor can monitor the condition of the machine in real time by receiving signals from various switches, sensors, and actuators installed to many parts of the machine and the information from the controllers which are controlling switches, etc.
Page 403
30 Testing and adjusting SEN02459-00 Executing monitoring Changing machine setting mode After the "Executing monitoring screen" is dis- To change the setting of the working mode, played, perform the necessary operation of the travel speed, or auto-deceleration during moni- machine and check the monitoring information. toring, operate the corresponding switch under a Monitoring information is indicated by the current condition, and the mode setting...
Page 404
SEN02459-00 30 Testing and adjusting Monitoring items table Unit (Initial setting: ISO) Com- Code ponent Monitoring item (Display on screen) Remarks meter inch charge 00200 Controller model select — PUMP 00201 Machine ID — 01002 Engine speed r/min 01601 2nd eng. speed command r/min PUMP 01100...
Page 405
30 Testing and adjusting SEN02459-00 Unit (Initial setting: ISO) Com- Code ponent Monitoring item (Display on screen) Remarks meter inch charge Bucket curl ON•OFF PUMP 01901 Pressure switch 2 Bucket dump ON•OFF PUMP Attachment ON•OFF PUMP Travel junction ON•OFF PUMP Swing brake ON•OFF PUMP...
Page 406
SEN02459-00 30 Testing and adjusting Unit (Initial setting: ISO) Com- Code ponent Monitoring item (Display on screen) Remarks meter inch charge 20228 Monitor prog. P/N — 20229 Pump con ass'y P/N — PUMP 20403 Pump con serial No — PUMP 20230 Pump con.
Page 407
30 Testing and adjusting SEN02459-00 Abnormality Record (Mechanical Systems) Information displayed on "abnormality record" screen The machine monitor classifies and records the On the "Mechanical Systems" screen, the fol- abnormalities which occurred in the past or which lowing information is displayed. are occurring at present into the mechanical sys- (a) : Occurrence order of abnormalities from tems, electrical systems, and air-conditioning sys-...
Page 408
SEN02459-00 30 Testing and adjusting Resetting abnormality record The contents of the mechanical system abnormality record cannot be reset. Abnormality Record (Electrical Systems) The machine monitor classifies and records the abnormalities which occurred in the past or which are occurring at present into the mechanical sys- tems, electrical systems, and air-conditioning sys- tem.
Page 409
30 Testing and adjusting SEN02459-00 Resetting abnormality record After the "Electrical Sys. Error Reset" While the "Electrical Systems" screen is screen is displayed, operate the function displayed, perform the following operation switches. with the numeral input switches. [F5]: Return to "Electrical systems" Operation of switches (While pressing screen (Reset mode) [4], perform the operation in order):...
Page 410
SEN02459-00 30 Testing and adjusting Failure codes table User Alarm Component Category of Failure code Trouble (Displayed on screen) code buzzer in charge record Electrical Engine controller lock caution 1 989L00 system Electrical Engine controller lock caution 2 989M00 system Electrical Engine controller lock caution 3 989N00...
Page 411
30 Testing and adjusting SEN02459-00 User Alarm Component Category of Failure code Trouble (Displayed on screen) code buzzer in charge record Electrical CA351 Inj. drive circuit error system Electrical CA352 Sensor sup. 1 volt. low error system Electrical CA386 Sensor sup. 1 volt. high error system Electrical CA435...
Page 412
SEN02459-00 30 Testing and adjusting User Alarm Component Category of Failure code Trouble (Displayed on screen) code buzzer in charge record Electrical DGH2KB Hydr oil sensor short PUMP system Electrical DHPAMA Pump press sensor abnormality PUMP system Electrical DHSFMA Travel left forward PPC press sensor abnormality PUMP system Electrical...
Page 413
30 Testing and adjusting SEN02459-00 a Entry order of items in table The items are entered in the order of their failure codes (incremental order). a User code Attached : If the failure code is detected, the user code, failure code, and telephone No. (if regis- tered) are displayed on the ordinary screen to notify the operator of the abnormality.
Page 414
SEN02459-00 30 Testing and adjusting Abnormality Record (Air-conditioning System) Information displayed on "abnormality record" screen The machine monitor classifies and records the On the "Air-conditioning System" screen, the abnormalities which occurred in the past or which following information is displayed. are occurring at present into the mechanical sys- (a): System/Component name tems, electrical systems, and air-conditioning...
Page 415
30 Testing and adjusting SEN02459-00 a The following items can be selected in the Maintenance Record maintenance record. The machine monitor records the maintenance information of the filters, oils, etc., which the opera- 01 Engine oil change tor can display and check by the following opera- 02 Engine oil filter change tions.
Page 416
SEN02459-00 30 Testing and adjusting a The following items can be selected on Maintenance Mode Change the Change of maintenance mode screen. The operating condition for maintenance function in the operation mode can be set and changed with 00 Maintenance mode on/off this menu.
Page 417
30 Testing and adjusting SEN02459-00 Contents of setting of each maintenance item Function of initializing all items After selecting each maintenance item, if the After selecting "All Default Value", if the screen screen is displayed, set the item with the func- is displayed, set with the function switches.
Page 418
SEN02459-00 30 Testing and adjusting a If [F6] is pressed without inputting a digit, Phone Number Entry there is not information of telephone No. The telephone No. displayed when the user code/ Accordingly, no telephone No. is displayed failure code is displayed in the operator mode can in the operator mode.
Page 419
30 Testing and adjusting SEN02459-00 Default (Key-on Mode) Mode at Previous Key-off: Final mode in previous operation is displayed when key Check or change various settings related to the is ON machine monitor and machine by "Default". [F3]: Move to lower item The function of working mode with key ON is used [F4]: Move to upper item to set the working mode displayed on the machine...
Page 420
SEN02459-00 30 Testing and adjusting a When the machine is delivered, the SI unit Default (Unit) system is set. Check or change various settings related to the machine monitor and machine by "Default". The unit selecting function is used to select the unit of the data displayed for monitoring, etc.
Page 421
30 Testing and adjusting SEN02459-00 a When an attachment is installed, if this Default (With/Without Attachment) setting is not carried out normally, the Check or change various settings related to the attachment cannot be set in the operator machine monitor and machine by "Default". mode.
Page 422
SEN02459-00 30 Testing and adjusting Default (Attachment/Maintenance Password) Selecting Disable/Enable After the Attachment/Maintenance Password Check or change various settings related to the screen is displayed, select the setting with the machine monitor and machine by "Default". function switches. The function of setting attachment/maintenance Disable : Password screen is not dis- password is used to set the display of the password played...
Page 423
30 Testing and adjusting SEN02459-00 Default (Camera) Selecting camera setting After the "Camera" setting screen is displayed, Check or change various settings related to the select the setting with the function switches. machine monitor and machine by "Default". OFF: Camera is not used The camera setting function is used to set installa- Original Image: Image of connected cam- tion and removal of a camera.
Page 424
SEN02459-00 30 Testing and adjusting a If ECO display is turned ON, ECO is dis- Default (ECO Display) played when the screen changes to the Check or change various settings related to the ordinary screen. Even if the energy saving machine monitor and machine by "Default".
Page 425
30 Testing and adjusting SEN02459-00 Adjustment (Pump Absorption Torque) Selecting absorption torque After the "Pump Absorption Torque" screen is The operator can adjust various items related to the displayed, select a set value on the right side machine with the machine monitor. with the function switches.
Page 426
SEN02459-00 30 Testing and adjusting Adjustment (Attachment Flow Adjustment) Selecting distribution of oil flow After the screen of "Attachment Flow Adjust- The operator can adjust various items related to the ment" is displayed, select a set value on the machine with the machine monitor. right side with the function switches.
Page 427
30 Testing and adjusting SEN02459-00 Cylinder Cut-Out The operator can perform "Cylinder Cut-Out" oper- ation with the machine monitor. "Cylinder Cut-Out" operation means to run the engine with 1 or more fuel injectors disabled electri- cally to reduce the number of effective cylinders. This operation is used to find out a cylinder which does not output power normally (combustion in it is abnormal).
Page 428
SEN02459-00 30 Testing and adjusting [Reference] No Injection If a normally operating cylinder is Cut-Out, If the engine is operated after long storage of the the following phenomena occur. machine, it may be worn or damaged because of 1) Lowering of engine speed insufficient lubrication with oil.
Page 429
30 Testing and adjusting SEN02459-00 Starting no injection cranking Prohibiting no injection cranking If no injection cranking (Fuel injection in no cyl- If the operator tries to perform the no injection inders) becomes effective, that is displayed on cranking while the engine is running, the mes- the screen.
Page 430
SEN02459-00 30 Testing and adjusting Fuel Consumption Display and function during test Clock mark (a) flashes during test. This function calculates the hourly fuel consump- a While the fuel consumption is being tion from the actual fuel consumption in a testing tested, the operator can work with the period and indicates it.
Page 431
30 Testing and adjusting SEN02459-00 KOMTRAX Settings (Terminal Status) Contents of display of terminal status On the "Terminal Status" screen, the following The setting condition and operating condition of items are displayed. K O MT RA X c an be c hec k ed wi th Di sp lay of Terminal type: Model name of KOMTRAX KOMTRAX setting.
Page 432
SEN02459-00 30 Testing and adjusting KOMTRAX Settings (GPS & Communication Status) Contents of display of GPS & communication status The setting condition and operating condition of On the screen of "GPS & Communication Sta- KOMTRAX can be checked with "KOMTRAX Set- tus", the following items are displayed.
Page 433
30 Testing and adjusting SEN02459-00 KOMTRAX Setting (MODEM S/N: TH300) Contents of display of Modem S/N The serial No. of TH300 Modem is displayed. The setting condition and operating condition of [F5]: Return to KOMTRAX settings screen K O MT RA X c an be c hec k ed wi th Di sp lay of KOMTRAX setting.
Page 434
SEN02459-00 30 Testing and adjusting KOMTRAX Settings (IP Address: TH200/201) Contents of display of IP address The telephone No. and IP address (2 systems) The setting condition and operating condition of of TH200 MODEM are displayed. K O MT RA X c an be c hec k ed wi th Di sp lay of [F5]: Return to KOMTRAX setting screen KOMTRAX settings.
Page 435
30 Testing and adjusting SEN02459-00 Display of KOMTRAX message Display of message (with return mail function) If a box to enter a value with the numeral keys Special messages for the serviceman sent from the is displayed under the message, enter a KOMTRAX base station (a distributor, etc.) can be proper number with the numeral input switches checked with this function.
SEN02460-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 30 Testing and adjusting Testing and adjusting, Part 3 Handling voltage circuit of engine controller ....................2 Preparation work for troubleshooting of electrical system ................3 Procedure for testing diodes ...........................
SEN02460-01 30 Testing and adjusting Handling voltage circuit of engine controller Before disconnecting or connecting a connec- tor between the engine controller and engine, be sure to turn the starting switch OFF. If a T-adapter is inserted in or connected to a connector between the engine controller and engine for troubleshooting, do not start the engine.
30 Testing and adjusting SEN02460-01 Preparation work for Insert or connect troubleshooting T-adapt- ers in or to connectors CM01, CM02, and troubleshooting of electrical CM03 of machine monitor (4). system a Connectors CM02 and CM03 are of a When carrying out troubleshooting of an elec- the same type.
Page 440
SEN02460-01 30 Testing and adjusting Pump controller Connect the troubleshooting adapters to Slide the operator's seat and seat stand to connectors C01 and C02 of pump control- the forward end. ler (12). a Install the adapters to only the wiring harness side.
Page 441
30 Testing and adjusting SEN02460-01 KOMTRAX communication module Connect troubleshooting T-adapters to con- Slide the operator's seat and seat stand to nectors CK01 and CK02 of KOMTRAX the forward end. communication module (13). a Cable (14) is for the communication antenna.
Page 442
SEN02460-01 30 Testing and adjusting Boost pressure and temperature sensor Supply pump IMV solenoid (Fuel regulator) a a a a Disconnection and connection of con- (Boost press & IMT) a a a a Disconnection and connection of con- nector nector The connector of the supply pump IMV The connector of the boost pressure and solenoid has a special locking mecha-...
Page 443
30 Testing and adjusting SEN02460-01 a a a a Precautions for connecting connector Engine coolant temperature sensor (Cool- Take care not to connect the connector ant temp) a a a a Disconnection and connection of con- reversely. Engage lock (e) on the wiring harness side nector with triangular notch (f) on the sensor side The connector of the engine coolant tem-...
SEN02460-01 30 Testing and adjusting Procedure for testing diodes a Test the assembled-type diode (8-pin) and the single diode (2-pin) according to the following procedure. a The conductive directions of the assembled- type diode are as follows. When using analog circuit tester Set the tester in the resistance range.
30 Testing and adjusting SEN02460-01 Pm Clinic service Model name Serial No. Service meter T PC138US-8 User's name Date of execution Inspector Specifications Main components Attachments Shoe width T Standard T ( T Breaker T 500 mm Boom T Standard T ( T 600 mm Bucket T Standard T ( T 700 mm...
Page 446
SEN02460-01 30 Testing and adjusting Check sheet (PC138US-8) Model Serial No. Service meter User's name Date of execution Inspector Engine Checking condition Standard Mea- Service limit Fuel Work- Auto- Check item Unit value for new sured Operation of work value control decel- machine...
Page 447
30 Testing and adjusting SEN02460-01 Hydraulic circuit Checking condition 600K 600K 600K 600K Checked part Fuel Work- Pump Pump Pump Pump control Operation of work equipment Control main 1 main 2 LS 1 LS 2 dial mode Self pressure All lever in neutral —...
Page 448
SEN02460-01 30 Testing and adjusting * Gauge changing work: Change [3] and [4] to 60K and change hoses of [3], [4], and [5]. [3b] [4b] [5a] Checking condition 600K 600K Check item Fuel Work- F pump R pump F pump R pump control Operation of work equipment...
Page 449
30 Testing and adjusting SEN02460-01 PC138US, USLC-8...
SEN02461-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting Failure code table and fuse locations Failure code table ............................2 Fuse locations..............................6 PC138US, USLC-8...
SEN02461-01 40 Troubleshooting Failure code table User Alarm Component Category of Reference Failure code Trouble (Displayed on screen) code buzzer in charge record documents No. Electrical 989L00 Engine controller lock caution 1 system Electrical 989M00 Engine controller lock caution 2 system Electrical 989N00...
Page 453
40 Troubleshooting SEN02461-01 User Alarm Component Category of Reference Failure code Trouble (Displayed on screen) code buzzer in charge record documents No. Electrical Troubleshooting CA331 Injector #2 (L #2) system open/short error system by failure code, Part 1 Electrical CA332 Injector #4 (L #4) system open/short error system SEN02463-00...
Page 454
SEN02461-01 40 Troubleshooting User Alarm Component Category of Reference Failure code Trouble (Displayed on screen) code buzzer in charge record documents No. Electrical DAFGMC GPS module error system Electrical DAFRMC CAN discon (Monitor detected) system Electrical DGH2KB Hydr oil sensor short PUMP system Electrical...
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40 Troubleshooting SEN02461-01 a Entry order of items in table The items are entered in the order of their failure codes (incremental order). a User code Attached : If the failure code is detected, the user code, failure code, and telephone No. (if regis- tered) are displayed on the ordinary screen to notify the operator of the abnormality.
SEN02461-01 40 Troubleshooting Fuse locations Connection table of fuse box a This connection table shows the devices to which each power supply of the fuse box supplies power (A switch power supply is a device which supplies power while the starting switch is in the ON position and a constant power supply is a device which supplies power while the starting switch is in the OFF and ON positions).
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40 Troubleshooting SEN02461-01 Locations of fusible links Location of fuse box and fuse Nos. PC138US, USLC-8...
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SEN02462-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting General information on troubleshooting Points to remember when troubleshooting ..................... 2 Sequence of events in troubleshooting......................3 Checks before troubleshooting ........................4 Classification and procedures for troubleshooting ..................
SEN02462-00 40 Troubleshooting Points to remember when troubleshooting Stop the machine in a level place, and check that the safety pin, blocks, and parking brake are securely fitted. When carrying out the operation with 2 or more workers, keep strictly to the agreed signals, and do not allow any unauthorized person to come near.
SEN02462-00 40 Troubleshooting Checks before troubleshooting Item Criterion Remedy 1. Check of level and type of fuel — Add fuel 2. Check of fuel for foreign matter — Clean and drain 3. Check of fuel filter — Replace 4. Check of hydraulic oil level —...
40 Troubleshooting SEN02462-00 Classification and procedures for troubleshooting Classification for troubleshooting Mode Contents Display of code Troubleshooting by failure code E-mode Troubleshooting of electrical system H-mode Troubleshooting of hydraulic and mechanical system S-mode Troubleshooting of engine Procedure for troubleshooting If a phenomenon looking like a trouble occurs in the machine, select a proper troubleshooting No. according to the following procedure, and then go to the corresponding troubleshooting section.
SEN02462-00 40 Troubleshooting Information in troubleshooting table a The following information is summarized in the troubleshooting table and the related electrical circuit diagram. Before carrying out troubleshooting, understand that information fully. User code Failure code Trouble name displayed in abnormality record machine moni- Display on Trouble Display on machine...
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40 Troubleshooting SEN02462-00 Related circuit diagram This drawing is a part of the electric circuit diagram related to trouble- shooting. Connector No.: Indicates (Model – Number of pins) and (Color). “Connector No. and pin No.” from each branching/merging point: Shows the ends of branch or source of merging within the parts of the same wiring harness.
SEN02462-00 40 Troubleshooting Phenomena looking like troubles and troubleshooting Nos. Troubleshooting Phenomena looking like troubles Display E-mode H-mode S-mode of code Phenomena related to user code/failure code User code and failure code are displayed on ordinary screen of machine monitor Accord- When abnormality record is checked, failure code is displayed in ing to dis-...
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40 Troubleshooting SEN02462-00 Troubleshooting Phenomena looking like troubles Display E-mode H-mode S-mode of code 34 Hydraulic drift of work equipment is large H-10 35 Time lag of work equipment is large H-11 Flow rate in attachment circuit cannot be adjusted (when attachment is H-26 installed) Phenomena related to compound operation...
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SEN02462-00 40 Troubleshooting Troubleshooting Phenomena looking like troubles Display E-mode H-mode S-mode of code Other phenomena 68 KOMTRAX system does not operate normally E-26 PC138US, USLC-8...
40 Troubleshooting SEN02462-00 Wiring table for connector pin numbers (Rev. 2006.11) a The terms of male and female refer to the pins, while the terms of male housing and female housing refer to the mating portion of the housing. PC138US, USLC-8...
SEN02462-00 40 Troubleshooting T-adapter box and T-adapter table (Rev. 2006.11) a The vertical column indicates a part number of T-branch box or T-branch adapter while the horizontal column indicates a part number of harness checker assembly. T-adapter kit Identification Part No. Part name symbol 799-601-2600 T-box (for ECONO)
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40 Troubleshooting SEN02462-00 T-adapter kit Identification Part No. Part name symbol q q q 799-601-7120 Adapter for M q q q 799-601-7130 Adapter for M 799-601-7340 Adapter for M q q q 799-601-7140 Adapter for S q q q 799-601-7150 Adapter for S (White) S10P q q q 799-601-7160 Adapter for S (Blue)
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SEN02462-00 40 Troubleshooting T-adapter kit Identification Part No. Part name symbol 799-601-9320 T-box (for DT/HD) 799-601-9330 Case 799-601-9340 Case 799-601-9350 Adapter for DRC DRC-40 799-601-9360 Adapter for DRC DRC-24 799-601-9410* Socket for engine (CRI-T2) Adapter for engine (CRI-T2) 799-601-9420 Adapter for engine (CRI-T3) PFUEL Socket for engine (CRI-T2) 799-601-9430* Socket for engine (CRI-T3) PCV...
SEN02463-01 40 Troubleshooting Failure code [AB00KE] Charge voltage low User code Failure code Charge voltage low Trouble (Machine monitor system) — AB00KE Contents of • While engine is running, signal circuit of alternator detected low charge voltage (below 7.8 V). trouble Action of •...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
40 Troubleshooting SEN02463-01 Failure code [B@BCNS] Eng coolant overheat User code Failure code Engine coolant overheat Trouble (Engine controller system) — B@BCNS Contents of • While engine was running, signal circuit of engine coolant temperature sensor detected overheating trouble of engine coolant (above about 102°C). Action of •...
SEN02463-01 40 Troubleshooting Failure code [CA111] ECM critical internal failure User code Failure code ECM critical internal failure Trouble (Engine controller system) CA111 Contents of • Abnormality occurred in controller. trouble Action of • None in particular. controller Problem that appears on •...
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40 Troubleshooting SEN02463-01 Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON. Wiring harness between CE02 (female) (55) Resis- Min. 1 Mz – R23 (1) and chassis ground tance Wiring harness between CE02 (female) (55) Resis-...
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SEN02463-01 40 Troubleshooting Circuit diagram related PC138US, USLC-8...
40 Troubleshooting SEN02463-01 Failure code [CA115] Eng. Ne and Bkup speed sensor error User code Failure code Eng. Ne and Bkup speed sensor error Trouble (Engine controller system) CA115 Contents of • Abnormality occurred in Ne speed sensor circuit and Bkup speed sensor circuit simultaneously. trouble Action of •...
SEN02463-01 40 Troubleshooting Failure code [CA122] Charge air press sensor high error User code Failure code Charge air press sensor high error Trouble (Engine controller system) CA122 Contents of • High voltage was detected in charge pressure sensor circuit. trouble Action of •...
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40 Troubleshooting SEN02463-01 Causes Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON. Wiring harness between CE01 (female) (19) – PTIM (female) (1) and wiring harness Resis- Min.
SEN02463-01 40 Troubleshooting Failure code [CA131] Throttle sensor high error User code Failure code Throttle sensor high error Trouble (Engine controller system) CA131 Contents of • High voltage was detected in fuel control dial circuit. trouble Action of • Sets throttle angle with signal other than fuel control dial signal and continues operation controller (depending on each model) Problem that...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
SEN02463-01 40 Troubleshooting Failure code [CA132] Throttle sensor low error User code Failure code Throttle sensor low error Trouble (Engine controller system) CA132 Contents of • Low voltage was detected in fuel control dial circuit. trouble Action of • Sets throttle angle with signal other than fuel control dial signal and continues operation controller (depending on each model) Problem that...
40 Troubleshooting SEN02463-01 Failure code [CA144] Coolant temp. sensor high error User code Failure code Coolant temp. sensor high error Trouble (Engine controller system) CA144 Contents of • High voltage was detected in coolant temperature sensor circuit. trouble Action of •...
40 Troubleshooting SEN02463-01 Failure code [CA153] Charge air temp. sensor high error User code Failure code Charge air temp. sensor high error Trouble (Engine controller system) CA153 Contents of • High voltage was detected in charge temperature sensor circuit. trouble Action of •...
SEN02463-01 40 Troubleshooting Failure code [CA154] Charge air temp. sensor low error User code Failure code Charge air temp. sensor low error Trouble (Engine controller system) CA154 Contents of • Low voltage was detected in charge temperature sensor circuit. trouble Action of •...
SEN02463-01 40 Troubleshooting Failure code [CA221] Ambient air press. sensor high error User code Failure code Ambient air press. sensor high error Trouble (Engine controller system) CA221 Contents of • High voltage was detected in ambient pressure sensor circuit. trouble Action of •...
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40 Troubleshooting SEN02463-01 Causes Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON. Wiring harness between CE01 (female) (36) – PAMB (female) (1) and wiring harness Resis- Min.
SEN02463-01 40 Troubleshooting Failure code [CA227] Sensor sup. 2 volt. high error User code Failure code Sensor sup. 2 volt. high error Trouble (Engine controller system) CA227 Contents of • High voltage was detected in sensor power supply 2 (5 V) circuit. trouble •...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
SEN02463-01 40 Troubleshooting Failure code [CA238] Ne speed sensor sup. volt. error User code Failure code Ne speed sensor sup. volt. error Trouble (Engine controller system) CA238 Contents of • Abnormality occurred in Ne speed sensor power supply (5 V) circuit. trouble Action of •...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
SEN02463-01 40 Troubleshooting Failure code [CA271] IMV/PCV1 short error User code Failure code IMV/PCV1 short error Trouble (Engine controller system) CA271 Contents of • There is short circuit in IMV circuit of supply pump. trouble Action of • None in particular. controller Problem that appears on...
40 Troubleshooting SEN02463-01 Failure code [CA272] IMV/PCV1 open error User code Failure code IMV/PCV1 open error Trouble (Engine controller system) CA272 Contents of • There is disconnection in IMV circuit of supply pump. trouble Action of • None in particular. controller Problem that appears on...
SEN02463-01 40 Troubleshooting Failure code [CA322] Injector #1 (L #1) system open/short error User code Failure code Injector #1 (L #1) system open/short error Trouble (Engine controller system) CA322 Contents of • There is disconnection or short circuit in injector #1 circuit. trouble Action of •...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
SEN02463-01 40 Troubleshooting Failure code [CA324] Injector #3 (L #3) system open/short error User code Failure code Injector #3 (L #3) system open/short error Trouble (Engine controller system) CA324 Contents of • There is disconnection or short circuit in injector #3 circuit. trouble Action of •...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
SEN02463-01 40 Troubleshooting Failure code [CA331] Injector #2 (L #2) system open/short error User code Failure code Injector #2 (L #2) system open/short error Trouble (Engine controller system) CA331 Contents of • There is disconnection or short circuit in injector #2 circuit. trouble Action of •...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
SEN02463-01 40 Troubleshooting Failure code [CA332] Injector #4 (L #4) system open/short error User code Failure code Injector #4 (L #4) system open/short error Trouble (Engine controller system) CA332 Contents of • There is disconnection or short circuit in injector #4 circuit. trouble Action of •...
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40 Troubleshooting SEN02463-01 Circuit diagram related PC138US, USLC-8...
SEN02464-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting Troubleshooting by failure code, Part 2 Failure code [CA351] Inj. drive circuit error..................... 3 Failure code [CA352] Sensor sup. 1 volt. low error ..................6 Failure code [CA386] Sensor sup.
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SEN02464-01 40 Troubleshooting Failure code [CA2185] Throttle sens. sup. volt. high error................28 Failure code [CA2186] Throttle sens. sup. volt. low error ................30 Failure code [CA2249] Rail press. very low error..................30 Failure code [CA2311] Abnormality in IMV solenoid ..................31 Failure code [D110KB] Battery relay drive short ...................
40 Troubleshooting SEN02464-01 Failure code [CA351] Inj. drive circuit error User code Failure code Inj. drive circuit error Trouble (Engine controller system) CA351 Contents of • Abnormality occurred in injector drive circuit. trouble Action of • Limits output and continues operation (Limits common rail pressure). controller Problem that appears on...
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SEN02464-01 40 Troubleshooting Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON. Wiring harness between CE02 (female) (55) Resis- Min. 1 Mz – R23 (1) and chassis ground tance Wiring harness between CE02 (female) (55) Resis-...
Page 556
40 Troubleshooting SEN02464-01 Circuit diagram related PC138US, USLC-8...
SEN02464-01 40 Troubleshooting Failure code [CA386] Sensor sup. 1 volt. high error User code Failure code Sensor sup. 1 volt. high error Trouble (Engine controller system) CA386 Contents of • High voltage was detected in sensor power supply 1 (5 V) circuit. trouble Action of •...
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40 Troubleshooting SEN02464-01 Circuit diagram related PC138US, USLC-8...
40 Troubleshooting SEN02464-01 Failure code [CA441] Battery voltage low error User code Failure code Battery voltage low error Trouble (Engine controller system) CA441 Contents of • Low voltage was detected in controller power supply voltage circuit. trouble Action of • None in particular. controller Problem that appears on...
SEN02464-01 40 Troubleshooting Failure code [CA449] Rail press. very high error User code Failure code Rail press. very high error Trouble (Engine controller system) CA449 Contents of • Common rail pressure sensor circuit detected abnormally high pressure (level 2). trouble Action of •...
SEN02464-01 40 Troubleshooting Failure code [CA451] Rail press. sensor high error User code Failure code Rail press. sensor high error Trouble (Engine controller system) CA451 Contents of • High voltage was detected in common rail pressure sensor circuit. trouble Action of •...
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40 Troubleshooting SEN02464-01 Causes Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON. Wiring harness between CE01 (female) (36) – PFUEL (female) (1) and Resis- Min.1 Mz wiring harness between CE01 (female) (29) tance –...
40 Troubleshooting SEN02464-01 Failure code [CA559] Rail press. low error User code Failure code Rail press. low error Trouble (Engine controller system) CA559 Contents of • Supply pump does not feed fuel (level 1). trouble Action of • Limits common rail pressure. controller Problem that appears on...
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SEN02464-01 40 Troubleshooting Check sheet for no-pressure feed Model Work No. Machine serial No. Date of check Engine Service meter Engine serial No. Worker's name A. Visual check Good NG Fuel leakage to outside Clogging of fuel tank breather B. Check with machine monitor (Fault history function, monitoring function, and reduced cylinder mode function) Good NG Check of failure code Check of monitoring information...
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40 Troubleshooting SEN02464-01 *1 – *10: See Testing and adjusting, "Special functions of machine monitor", Monitoring items table. A limit value is the value mentioned above, but a standard value in normalcy is "0 cc/min. (no leak)". Rating or equivalent: Relieve the circuit under the following condition.
SEN02464-01 40 Troubleshooting Failure code [CA689] Eng. Ne speed sensor error User code Failure code Eng. Ne speed sensor error Trouble (Engine controller system) CA689 Contents of • Abnormality occurred in engine Ne speed sensor circuit. trouble Action of • Operates with signals of Bkup speed sensor. controller Problem that •...
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40 Troubleshooting SEN02464-01 Causes Standard value in normal state/Remarks on troubleshooting Possible causes and standard If causes 1 – 6 are not detected, engine controller may be defec- value in normal 7 Defective engine controller tive. (Since trouble is in system, troubleshooting cannot be carried state out.) Circuit diagram related...
SEN02464-01 40 Troubleshooting Failure code [CA2185] Throttle sens. sup. volt. high error User code Failure code Throttle Sens. sup. volt. high error Trouble (Engine controller system) CA2185 Contents of • High voltage was detected in throttle sensor power supply (5 V) circuit. trouble Action of •...
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40 Troubleshooting SEN02464-01 Circuit diagram related PC138US, USLC-8...
40 Troubleshooting SEN02464-01 Failure code [CA2311] Abnormality in IMV solenoid User code Failure code Abnormality in IMV solenoid Trouble (Engine controller system) CA2311 Contents of • Resistance in supply pump actuator is abnormally high or low. trouble Action of • None in particular. controller Problem that appears...
SEN02464-01 40 Troubleshooting Failure code [D19JKZ] Personal code relay abnormality User code Failure code Personal code relay abnormality Trouble (KOMTRAX system in machine monitor) D19JKZ Contents of • Disconnection or short circuit was detected in personal code relay circuit. trouble •...
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40 Troubleshooting SEN02464-01 Circuit diagram related PC138US, USLC-8...
SEN02464-01 40 Troubleshooting Failure code [DA22KK] Pump solenoid power low error User code Failure code Lowering of solenoid power supply voltage Trouble (Pump controller system) DA22KK Contents of • Solenoid power supply voltage of controller is below 20 V. trouble •...
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40 Troubleshooting SEN02464-01 Circuit diagram related PC138US, USLC-8...
SEN02464-01 40 Troubleshooting Failure code [DA25KP] 5V sensor 1 power abnormality User code Failure code 5V sensor power supply output 1 abnormality Trouble (Pump controller system) — DA25KP Contents of • Voltage of 5V sensor power supply output 1 circuit is below 2.5 V or above 6.0 V. trouble Action of •...
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40 Troubleshooting SEN02464-01 Cause Standard value in normal state/Remarks on troubleshooting Wiring harness between C01 (female) (16) – P08 (female) (2), P08 (female) (1) – J03 – Resis- Min. 1 Mz ground (T08) tance Ground fault in wiring har- [Swing LEFT PPC pressure switch system] ness (Short circuit with GND circuit) Wiring harness between C01 (female) (9) –...
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SEN02464-01 40 Troubleshooting Circuit diagram related PC138US, USLC-8...
40 Troubleshooting SEN02464-01 Failure code [DA26KP] 5V sensor 2 power abnormality User code Failure code 5V sensor power supply output 2 abnormality Trouble (Pump controller system) — DA26KP Contents of • Voltage of 5V sensor power supply output 2 circuit is below 2.5 V or above 6.0 V. trouble Action of •...
SEN02465-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting Troubleshooting by failure code, Part 3 Failure code [DA2RMC] CAN discon (Pump controller detected)..............4 Failure code [DAF8KB] Short circuit in camera power supply ................ 6 Failure code [DAFGMC] GPS module error....................
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SEN02465-01 40 Troubleshooting Failure code [DW45KA] Swing brake sol discon................... 32 Failure code [DW45KB] Swing brake sol short ..................... 34 Failure code [DW91KA] Travel junction sol discon ..................36 Failure code [DW91KB] Travel junction sol short..................37 Failure code [DWJ0KA] Merge-divider sol discon..................38 Failure code [DWJ0KB] Merge-divider sol short ...................
SEN02465-01 40 Troubleshooting Failure code [DA2RMC] CAN discon (Pump controller detected) User code Failure code CAN disconnection (Pump controller detected) Trouble (Pump controller system) DA2RMC Contents of • Pump controller detected communication error in CAN communication circuit between machine trouble monitor and engine controller.
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DAF8KB] Short circuit in camera power supply User code Failure code Short circuit in camera power supply Trouble (Machine monitor system) — DAF8KB Contents of • Output power supply voltage (Rating: 8 V) from machine monitor to camera is below 6.0 V or above trouble 10 V.
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DAFGMC] GPS module error User code Failure code GPS module operation error Trouble (KOMTRAX system in machine monitor) — DAFGMC Contents of • Position data is not sent from GPS module (in machine monitor) to KOMTRAX communication trouble MODEM in 50 seconds after KOMTRAX is started.
SEN02465-01 40 Troubleshooting Failure code [DAFRMC] CAN discon (Monitor detected) User code Failure code CAN disconnection (Monitor detected) Trouble (Machine monitor system) DAFRMC Contents of • Machine monitor detected communication error in CAN communication circuit between pump con- trouble troller and engine controller. Action of •...
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DGH2KB] Hydr oil sensor short User code Failure code Hydraulic oil temperature sensor short Trouble (Pump controller system) — DGH2KB Contents of • Ground fault was detected in hydraulic oil temperature sensor circuit. trouble Action of •...
SEN02465-01 40 Troubleshooting Failure code [DHPAMA] Pump press sensor abnormality User code Failure code Pump pressure sensor abnormality Trouble (Pump controller system) — DHPAMA Contents of • Signal voltage of pump pressure sensor circuit is below 0.3 V or above 4.4 V. trouble Action of •...
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DHSFMA] Travel left forward PPC press sensor abnormality User code Failure code Travel left forward PPC pressure sensor abnormality Trouble (Pump controller system) DHSFMA Contents of • Signal voltage of travel left forward PPC pressure sensor circuit is below 0.3 V or above 4.5 V. trouble Action of •...
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DHSGMA] Travel right forward PPC press sensor abnormality User code Failure code Travel right forward PPC pressure sensor abnormality Trouble (Pump controller system) DHSGMA Contents of • Signal voltage of travel right forward PPC pressure sensor circuit is below 0.3 V or above 4.5 V. trouble Action of •...
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DHSHMA] Travel left reverse PPC press sensor abnormality User code Failure code Travel left reverse PPC pressure sensor abnormality Trouble (Pump controller system) DHSHMA Contents of • Signal voltage of travel left reverse PPC pressure sensor circuit is below 0.3 V or above 4.5 V. trouble Action of •...
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DHSJMA] Travel right reverse PPC press sensor abnormality User code Failure code Travel right reverse PPC pressure sensor abnormality Trouble (Pump controller system) DHSJMA Contents of • Signal voltage of travel right reverse PPC pressure sensor circuit is below 0.3 V or above 4.5 V. trouble Action of •...
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DHX1MA] Overload sensor abnormality (Analog) User code Failure code Overload sensor (Analog) Trouble (Pump controller system) — DHX1MA Contents of • Monitor which is not set to be displayed (Overload alarm monitor) is displayed. trouble Action of •...
40 Troubleshooting SEN02465-01 Failure code [DV20KB] Travel alarm S/C User code Failure code Travel alarm S/C Trouble (Pump controller system) — DV20KB Contents of • Abnormal current flowed in the travel alarm circuit, when power is supplied to the circuit. trouble •...
SEN02465-01 40 Troubleshooting Failure code [DW43KA] Travel speed sol discon User code Failure code Travel speed solenoid system disconnection Trouble (Pump controller system) — DW43KA Contents of • When output to travel speed shifting solenoid was turned ON, disconnection was detected in circuit. trouble Action of •...
40 Troubleshooting SEN02465-01 Failure code [DW43KB] Travel speed sol short User code Failure code Travel speed solenoid system short Trouble (Pump controller system) — DW43KB Contents of • When output to travel speed shifting solenoid was turned ON, short circuit was detected in circuit. trouble Action of •...
SEN02465-01 40 Troubleshooting Failure code [DW45KA] Swing brake sol discon User code Failure code Swing holding brake solenoid system disconnection Trouble (Pump controller system) DW45KA Contents of • When output to swing holding brake solenoid was turned OFF, disconnection was detected in cir- trouble cuit.
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40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DW45KB] Swing brake sol short User code Failure code Swing holding brake solenoid system short Trouble (Pump controller system) DW45KB Contents of • When output to swing holding brake solenoid was turned ON, short circuit was detected in circuit. trouble Action of •...
Page 630
40 Troubleshooting SEN02465-01 Circuit diagram related PC138US, USLC-8...
SEN02465-01 40 Troubleshooting Failure code [DW91KA] Travel junction sol discon User code Failure code Travel junction solenoid system disconnection Trouble (Pump controller system) — DW91KA Contents of • When output to travel junction solenoid was turned ON, disconnection was detected in circuit. trouble Action of •...
40 Troubleshooting SEN02465-01 Failure code [DW91KB] Travel junction sol short User code Failure code Travel junction solenoid system short Trouble (Pump controller system) — DW91KB Contents of • When output to travel junction solenoid was turned ON, short circuit was detected in circuit. trouble Action of •...
SEN02465-01 40 Troubleshooting Failure code [DWJ0KA] Merge-divider sol discon User code Failure code Merge-divider solenoid disconnection Trouble (Pump controller system) — DWJ0KA Contents of • When merge-divider EPC solenoid was driven, disconnection was detected in circuit. trouble Action of • None in particular (Since no current flows, solenoid does not operate). controller •...
40 Troubleshooting SEN02465-01 Failure code [DWJ0KB] Merge-divider sol short User code Failure code Merge-divider solenoid short Trouble (Pump controller system) — DWJ0KB Contents of • When merge-divider EPC solenoid was driven, short circuit was detected in circuit. trouble Action of •...
SEN02466-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting Troubleshooting by failure code, Part 4 Failure code [DXA8KA] PC-EPC sol discon ....................2 Failure code [DXA8KB] PC-EPC sol short...................... 4 Failure code [DXE4KA] Service current EPC discon ..................
SEN02466-00 40 Troubleshooting Failure code [DXA8KA] PC-EPC sol discon User code Failure code PC-EPC solenoid system disconnection Trouble (Pump controller system) DXA8KA Contents of • When PC-EPC solenoid was driven, disconnection was detected in circuit. trouble Action of • None in particular (Since no current flows, solenoid does not operate). controller •...
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40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
SEN02466-00 40 Troubleshooting Failure code [DXA8KB] PC-EPC sol short User code Failure code PC-EPC solenoid system short Trouble (Pump controller system) DXA8KB Contents of • When PC-EPC solenoid was driven, short circuit was detected in circuit. trouble Action of • Turns output to PC-EPC solenoid OFF. controller •...
Page 640
40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
SEN02466-00 40 Troubleshooting Failure code [DXE4KA] Service current EPC discon User code Failure code Service current EPC solenoid disconnection Trouble (Pump controller system) — DXE4KA Contents of • When service EPC solenoid was driven, disconnection was detected in circuit. trouble Action of •...
40 Troubleshooting SEN02466-00 Failure code [DXE4KB] Service current EPC short User code Failure code Service current EPC solenoid short Trouble (Pump controller system) — DXE4KB Contents of • When service EPC solenoid was driven, short circuit was detected in circuit. trouble Action of •...
SEN02466-00 40 Troubleshooting Failure code [DY20KA] Wiper working abnormality User code Failure code Wiper working abnormality Trouble (Pump controller system) — DY20KA Contents of • When windshield wiper works, W signal of working ends is not input. trouble Action of •...
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40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
SEN02466-00 40 Troubleshooting Failure code [DY20MA] Wiper parking abnormality User code Failure code Wiper parking abnormality Trouble (Pump controller system) — DY20MA Contents of • When windshield wiper parks, P signal of storage area is not input. trouble Action of •...
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40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
SEN02466-00 40 Troubleshooting Failure code [DY2CKA] Washer drive discon User code Failure code Window washer drive system disconnection Trouble (Pump controller system) — DY2CKA Contents of • When output to window washer drive system was turned OFF (when ground circuit was connected), trouble disconnection was detected in circuit.
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40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
SEN02466-00 40 Troubleshooting Failure code [DY2CKB] Washer drive short User code Failure code Window washer drive system short Trouble (Pump controller system) — DY2CKB Contents of • When output to window washer drive system was turned ON (ground circuit was disconnected), trouble short circuit was detected in circuit.
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40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
SEN02466-00 40 Troubleshooting Failure code [DY2DKB] Wiper drive (for) short User code Failure code Wiper motor drive forward system short Trouble (Pump controller system) — DY2DKB Contents of • When output to wiper motor drive forward side was turned ON, short circuit was detected in circuit. trouble Action of •...
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40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
SEN02466-00 40 Troubleshooting Failure code [DY2EKB] Wiper drive (rev) short User code Failure code Wiper motor drive reverse system short Trouble (Pump controller system) — DY2EKB Contents of • When output to wiper motor drive reverse side was turned ON, short circuit was detected in circuit. trouble Action of •...
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40 Troubleshooting SEN02466-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting Troubleshooting of electrical system (E-mode) Before carrying out troubleshooting of electrical system ................3 Information in troubleshooting table........................ 5 E-1 When starting switch turned ON, machine monitor displays nothing ............
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SEN02467-00 40 Troubleshooting E-13 Machine monitor does not display some items..................27 E-14 Function switch does not work ......................27 E-15 Auto-decelerator does not operate normally ..................28 E-16 Working mode does not change ......................29 E-17 Travel speed does not change ......................30 E-18 Alarm buzzer cannot be stopped......................
40 Troubleshooting SEN02467-00 Before carrying out troubleshooting of electrical system Connection table of fuse box a This connection table shows the devices to which each power supply of the fuse box supplies power (A switch power supply is a device which supplies power while the starting switch is in the ON position and a constant power supply is a device which supplies power while the starting switch is in the OFF and ON positions).
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SEN02467-00 40 Troubleshooting Locations of fusible links Location of fuse box and fuse Nos. PC138US, USLC-8...
40 Troubleshooting SEN02467-00 Information in troubleshooting table a The following information is summarized in the troubleshooting table and the related electrical circuit diagram. Before carrying out troubleshooting, understand that information fully. Trouble Trouble which occurred in the machine Related Information related to detected trouble or troubleshooting information Cause Standard value in normal state/Remarks on troubleshooting...
• When starting switch turned ON, machine monitor displays nothing. • When starting switch is turned ON, machine monitor displays KOMATSU logo, screen to input pass- word (if set), screen to check breaker mode (if set), screen of check before starting, screen to check Related working mode and travel speed, and ordinary screen in order.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
SEN02467-00 40 Troubleshooting E-2 When starting switch turned ON (before starting engine), basic check item lights up Trouble • Engine oil level monitor lights up red. Related • Condition of engine oil level switch signal can be checked with monitoring function. information (Code: 04501 Monitor input 2) Cause...
40 Troubleshooting SEN02467-00 E-3 Engine does not start (Engine does not turn) Trouble • Engine does not start (Engine does not turn). • Engine starting circuit has following 2 start lock mechanisms. Related 1) Start lock with password of machine monitor information 2) Start lock with lock lever Cause...
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SEN02467-00 40 Troubleshooting Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then turn starting switch ON and carry out troubleshooting. Defective alternator (Internal Alternator Voltage short circuit) Between L (AR-1) – Generation output Max. 1 V chassis ground a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
SEN02467-00 40 Troubleshooting E-4 Preheater does not operate Trouble (1) When starting switch is turned to HEAT position, preheating monitor does not light up or flash. • Preheater monitor lights up when starting switch is turned to HEAT and starts flashing about 30 sec- onds after to notify completion of preheating (It stops flashing about 10 seconds after).
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
SEN02467-00 40 Troubleshooting E-5 Automatic warm-up system does not operate (in cold season) Trouble • Automatic warm-up system does not operate (in cold season). • When engine coolant temperature is below 30°C automatic warm-up system raises engine speed to 1,300 rpm. •...
SEN02467-00 40 Troubleshooting E-6 All work equipment, swing, and travel mechanism do not move or cannot be locked Trouble (1) All work equipment, swing, and travel mechanism do not move. Related information Cause Standard value in normal state/Remarks on troubleshooting 1 Defective fuse No.
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40 Troubleshooting SEN02467-00 Trouble (2) All work equipment, swing, and travel mechanism cannot be locked. Related information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON. Defective lock lever switch S14 (female) Lock lever...
SEN02467-00 40 Troubleshooting E-7 Precaution lights up while engine is running Trouble (1) Charge level monitor lights up red. Related • Signal voltage of alternator can be checked with monitoring function. information (Code: 04300 Charge voltage) Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (2) Fuel level monitor lights up red. Related • Signal voltage of fuel sensor can be checked with monitoring function. information (Code: 04200 Fuel sensor voltage) Cause Standard value in normal state/Remarks on troubleshooting Fuel level may be low (below about 41 l). Check it and add fuel if Possible causes Low fuel level (when system and standard...
40 Troubleshooting SEN02467-00 E-8 Emergency stop item lights up while engine is running Trouble (1) Engine coolant temperature monitor lights up red. • Signals of engine coolant temperature sensor are input to engine controller and then transmitted to Related machine monitor through communication system. information •...
SEN02467-00 40 Troubleshooting E-9 Engine coolant temperature gauge does not indicate normally (1) While engine coolant temperature is rising normally, temperature gauge does not rise from white Trouble range (C). (2) While engine coolant temperature is stabilized normally, temperature gauge rises to red range (H). •...
40 Troubleshooting SEN02467-00 E-10 Hydraulic oil temperature gauge does not indicate normally (1) While hydraulic oil temperature is rising normally, temperature gauge does not rise from white Trouble range (C). (2) While hydraulic oil temperature is stabilized normally, temperature gauge rises to red range (H). •...
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SEN02467-00 40 Troubleshooting (3) Display of hydraulic oil temperature gauge is different from actual hydraulic oil temperature. Trouble (4) Display of hydraulic oil temperature gauge is different from display of hydraulic oil temperature monitor. • Signals of hydraulic oil temperature sensor are input to pump controller and then transmitted to Related machine monitor through communication system.
40 Troubleshooting SEN02467-00 E-11 Fuel level gauge does not indicate normally (1) While fuel is added, fuel level gauge does not rise from red range (E). Trouble (2) While fuel level is low, fuel level gauge does not lower from green range top (F) Related •...
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SEN02467-00 40 Troubleshooting (3) Display of fuel level gauge is different from actual fuel level. Trouble (4) Display of fuel level gauge is different from display of fuel level monitor. Related • Signal voltage of fuel level sensor can be checked with monitoring function. information (Code: 04200 Fuel level sensor voltage) Cause...
40 Troubleshooting SEN02467-00 E-12 Contents of display by machine monitor are different from applicable machine Trouble Contents of display by machine monitor are different from applicable machine. Related information Cause Standard value in normal state/Remarks on troubleshooting a Turn starting switch ON and carry out troubleshooting (with monitoring function).
SEN02467-00 40 Troubleshooting E-15 Auto-decelerator does not operate normally (1) When auto-decelerator switch is operated, auto-decelerator monitor does not light up or does not Trouble go off. Related • Condition of signal of auto-decelerator switch can be checked with monitoring function. information (Code: 04504 Monitor 1st, 2nd line switches) Possible causes...
40 Troubleshooting SEN02467-00 E-16 Working mode does not change Trouble (1) When working mode switch is operated, working mode selection screen is not displayed. Related • Condition of signal of working mode switch can be checked with monitoring function. information (Code: 04504 Monitor 1st, 2nd line switches) Possible causes Cause...
SEN02467-00 40 Troubleshooting E-17 Travel speed does not change Trouble (1) When travel speed switch is operated, travel speed monitor does not change. Related • Condition of signal of travel speed switch can be checked with monitoring function. information (Code: 04504 Monitor 1st, 2nd line switches) Possible causes Cause Standard value in normal state/Remarks on troubleshooting...
40 Troubleshooting SEN02467-00 E-18 Alarm buzzer cannot be stopped Trouble • Alarm buzzer cannot be stopped. Related • Condition of signal of alarm buzzer cancel switch can be checked with monitoring function. information (Code: 04504 Monitor 1st, 2nd line switches) Possible causes Cause Standard value in normal state/Remarks on troubleshooting...
SEN02467-00 40 Troubleshooting E-19 Windshield wiper and window washer do not operate Trouble (1) When wiper switch is operated, wiper monitor does not light up or go off. Related • Condition of wiper switch signal can be checked with monitoring function. information (Code: 04504 Monitor 1st, 2nd line switches) Possible causes...
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SEN02467-00 40 Troubleshooting Trouble (3) When window washer switch is operated, window washer does not operate. Related • Condition of window washer switch signal can be checked with monitoring function. information (Code: 04504 Monitor 1st, 2nd line switches) Possible causes Cause Standard value in normal state/Remarks on troubleshooting and standard...
SEN02467-00 40 Troubleshooting E-20 Swing holding brake does not operate normally Trouble (1) When swing lock switch is operated, swing lock monitor does not light up or go off. • Condition of swing lock switch signal can be checked with monitoring function. Related (Machine monitor system code: 04502 Monitor input 3) information...
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
SEN02467-00 40 Troubleshooting E-21 Travel alarm does not sound or does not stop sounding • Alarm does not sound during travel. Trouble • Alarm does not stop sounding while machine is stopped. Related information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON.
40 Troubleshooting SEN02467-00 E-22 Air conditioner does not operate normally (including air conditioner abnormality record) Trouble (1) When air conditioner switch is operated, air conditioner control screen is not displayed. Related • Condition of air conditioner switch signal can be checked with monitoring function. information (Code: 04505 Monitor 3rd, 4th line switches, 04506 Monitor 5th line switch) Possible causes...
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SEN02467-00 40 Troubleshooting Trouble (3) Air does not come out (Air flow is insufficient). Related information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON (coil side). R20 (male) Resistance 140 –...
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40 Troubleshooting SEN02467-00 Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON. Wiring harness between R20 (female) (3) – Resis- Min. 1 Mz (wiring side) (36) tance Ground fault in wiring har- Wiring harness between R20 (female) (2) –...
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SEN02467-00 40 Troubleshooting Trouble (4) Air is not cooled (Cooling performance is insufficient). Related information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then carry out troubleshoot- ing without turning starting switch ON (coil side). R21 (male) Resistance 140 –...
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40 Troubleshooting SEN02467-00 (5) Air conditioner abnormality record: Communication condition “CAN disconnection”, Communica- Trouble tion condition “Abnormal” • While abnormality in communication is being detected, “CAN disconnection” is displayed. • If abnormality in communication has been detected and reset, “Abnormality” is displayed. Related •...
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SEN02467-00 40 Troubleshooting Trouble (6) Air conditioner abnormality record: Setting condition “Abnormality” • If setting of air conditioner controller model is different from setting of machine monitor model, “Abnormality” is displayed. Related • If “CAN disconnection” is displayed as communication condition, communication cannot be carried information out normally.
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40 Troubleshooting SEN02467-00 Trouble (8) Air conditioner abnormality record: External air sensor “Unused” • External air sensor is not used in air conditioner system of this machine. Related • If “CAN disconnection” is displayed as communication condition, communication cannot be carried information out normally.
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SEN02467-00 40 Troubleshooting Trouble (10) Air conditioner abnormality record: Daylight sensor “Abnormality” • If “CAN disconnection” is displayed as communication condition, communication cannot be carried Related out normally. Accordingly, this condition is not displayed. information • Method of reproducing abnormality record: Turn starting switch ON + Turn air conditioner (A/C) switch ON.
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40 Troubleshooting SEN02467-00 Trouble (11) Air conditioner abnormality record: Air outlet damper “Abnormality” • If “CAN disconnection” is displayed as communication condition, communication cannot be carried Related out normally. Accordingly, this condition is not displayed. information • Method of reproducing abnormality record: Turn starting switch ON + Turn air conditioner (A/C) switch ON.
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SEN02467-00 40 Troubleshooting Trouble (12) Air conditioner abnormality record: A/M damper “Abnormality” • If “CAN disconnection” is displayed as communication condition, communication cannot be carried Related out normally. Accordingly, this condition is not displayed. information • Method of reproducing abnormality record: Turn starting switch ON + Turn air conditioner (A/C) switch ON.
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40 Troubleshooting SEN02467-00 Trouble (13) Air conditioner abnormality record: Refrigerant “Abnormality” • If “CAN disconnection” is displayed as communication condition, communication cannot be carried Related out normally. Accordingly, this condition is not displayed. information • Method of reproducing abnormality record: Turn starting switch ON + Turn air conditioner (A/C) switch ON.
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SEN02467-00 40 Troubleshooting Circuit diagram related PC138US, USLC-8...
40 Troubleshooting SEN02467-00 E-23 While starting switch is in OFF position, service meter is not displayed Trouble • When starting switch is turned OFF, service meter is not displayed. • While starting switch is at OFF position, if following switches are operated, service meter is dis- Related played at top center of screen.
SEN02467-00 40 Troubleshooting E-25 Monitoring function does not display lever control signal normally Trouble (1) Boom raise operation is not displayed normally by monitoring function. Related • Monitoring code: 01900 Pressure switch 1 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (2) Arm curl operation is not displayed normally by monitoring function. Related • Monitoring code: 01900 Pressure switch 1 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (3) Bucket curl operation is not displayed normally by monitoring function. Related • Monitoring code: 01901 Pressure switch 2 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (4) Bucket dump operation is not displayed normally by monitoring function. Related • Monitoring code: 01901 Pressure switch 2 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (5) Boom lower operation is not displayed normally by monitoring function. Related • Monitoring code: 01900 Pressure switch 1 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (6) Arm dump operation is not displayed normally by monitoring function. Related • Monitoring code: 01900 Pressure switch 1 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (7) Swing operation is not displayed normally by monitoring function. Related • Monitoring code: 01900 Pressure switch 1 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
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SEN02467-00 40 Troubleshooting Trouble (8) Service operation is not displayed normally by monitoring function. Related • Monitoring code: 01901 Pressure switch 2 information Cause Standard value in normal state/Remarks on troubleshooting a Prepare with starting switch OFF, then start engine and carry out troubleshooting.
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40 Troubleshooting SEN02467-00 Circuit diagram related PC138US, USLC-8...
SEN02467-00 40 Troubleshooting E-26 KOMTRAX system does not operate normally Trouble • KOMTRAX system does not operate normally. • If KOMTRAX system administrator makes request for checking system on machine side for trouble, Related carry out following troubleshooting. information • Even if KOMTRAX system has trouble, it does not particularly appear on machine. •...
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SEN02468-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting Troubleshooting of hydraulic and mechanical system (H-mode) Information contained in troubleshooting table ....................3 System chart for hydraulic and mechanical systems ..................4 H-1 Speed or power of all work equipment, swing, and travel are low ............
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SEN02468-01 40 Troubleshooting H-13 Boom RAISE speed is low in compound operation of swing + boom RAISE........15 H-14 Travel speed lowers largely during compound operation of work equipment/swing + travel ....16 H-15 Machine deviates during travel......................17 H-16 Travel speed is low..........................18 H-17 Machine cannot be steered easily or steering power is low ..............
40 Troubleshooting SEN02468-01 Information contained in troubleshooting table a Troubleshooting table collectively carry the following information. Carry out troubleshooting work after fully grasping their contents. Trouble Phenomena occurring on machine Related Information on occurred failures and troubleshooting information Cause Standard value in normal state/Remarks on troubleshooting Cause for presumed Possible causes failure...
SEN02468-01 40 Troubleshooting System chart for hydraulic and mechanical systems PC138US, USLC-8...
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40 Troubleshooting SEN02468-01 a This is a system chart that has been drawn up by simplifying the whole hydraulic circuit chart. Use it as a reference material when troubleshooting the hydraulic and mechanical systems. PC138US, USLC-8...
SEN02468-01 40 Troubleshooting H-1 Speed or power of all work equipment, swing, and travel are low Trouble • Speed or power of all work equipment, swing, and travel are low. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it...
40 Troubleshooting SEN02468-01 H-2 Engine speed sharply drops or engine stalls Trouble • Engine speed sharply drops or the engine stalls. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
SEN02468-01 40 Troubleshooting H-3 No work equipment, travel and swing move Trouble • No work equipment, travel and swing move. Related • Set the working mode at P mode for the troubleshooting. information Cause Standard value in normal state/Remarks on troubleshooting Stop engine for preparations.
40 Troubleshooting SEN02468-01 H-5 Fine control mode does not function Trouble • Fine control mode does not function. Related • Set the working mode at P mode for the troubleshooting. information Cause Standard value in normal state/Remarks on troubleshooting The orifice in the LS circuit is presumed to be clogged. Check the 1 Orifice in LS circuit clogged orifice itself.
SEN02468-01 40 Troubleshooting H-6 Speed or power of boom is low Trouble • Speed or power of boom is low. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
40 Troubleshooting SEN02468-01 H-7 Speed or power of arm is low Trouble • Speed or power of arm is low. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
SEN02468-01 40 Troubleshooting H-8 Speed or power of bucket is low Trouble • Speed or power of bucket is low. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
40 Troubleshooting SEN02468-01 H-9 Work equipment does not move in its single operation (1) The boom does not move when operated indepen- dently. • Work equipment does not move in its sin- (2) The arm does not move when operated indepen- Trouble gle operation dently.
SEN02468-01 40 Troubleshooting H-10 Hydraulic drift of work equipment is large Trouble • Hydraulic drift of work equipment is large. (1) Hydraulic drift of boom is large. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
40 Troubleshooting SEN02468-01 H-11 Time lag of work equipment is large Trouble • Time lag of work equipment is large. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Possible causes Malfunction of control valve The regeneration valve of the control valve may have a malfunc- and standard...
SEN02468-01 40 Troubleshooting H-14 Travel speed lowers largely during compound operation of work equipment/swing + travel Trouble • Travel speed lowers largely during compound operation of work equipment/swing + travel. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it...
40 Troubleshooting SEN02468-01 H-15 Machine deviates during travel Trouble • Machine deviates during travel. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
SEN02468-01 40 Troubleshooting H-16 Travel speed is low Trouble • Travel speed is low. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
40 Troubleshooting SEN02468-01 H-17 Machine cannot be steered easily or steering power is low Trouble • Machine cannot be steered easily or steering power is low. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
SEN02468-01 40 Troubleshooting H-18 Travel speed does not change or it is kept low or high Trouble • Travel speed does not change or it is kept low or high. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it...
40 Troubleshooting SEN02468-01 H-20 Machine does not swing Trouble • Machine does not swing. (1) Machine does not swing in either direction. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
SEN02468-01 40 Troubleshooting H-21 Swing acceleration or swing speed is low (1) Swing acceleration or swing speed is low in both Trouble • Swing acceleration or swing speed is low. directions. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting...
40 Troubleshooting SEN02468-01 H-22 Excessive overrun when stopping swing (1) Overrun of upper structure is large in both direc- Trouble • Excessive overrun when stopping swing. tions. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it Possible causes running at high idle during the troubleshooting.
SEN02468-01 40 Troubleshooting H-23 When upper structure stops swinging, it makes large shock Trouble • When upper structure stops swinging, it makes large shock. Related • Conduct the troubleshooting in working mode P. information Cause Standard value in normal state/Remarks on troubleshooting Keep the engine stopped for the preparations, and keep it running at high idle during the troubleshooting.
40 Troubleshooting SEN02468-01 H-25 Hydraulic drift of swing is large Trouble • Hydraulic drift of swing is large. (1) When swing holding brake is operated • If the swing lock switch is turned ON or the swing holding brake release switch is in the normal posi- Related tion, the swing holding brake operates and the disc brake holds the upper structure.
SEN02468-01 40 Troubleshooting H-26 Flow rate in attachment circuit cannot be adjusted When attachment is installed Trouble • Flow rate in attachment circuit cannot be adjusted. • If an attachment is installed, the flow rate in the service circuit changes according to the selected Related working mode.
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SEN02469-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 40 Troubleshooting Troubleshooting of engine (S-mode) Method of using troubleshooting chart......................4 S-1 Starting performance is poor ........................8 S-2 Engine does not start ..........................9 S-3 Engine does not pick up smoothly......................
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SEN02469-01 40 Troubleshooting S-15 Abnormal noise is made ........................24 S-16 Vibration is excessive ........................... 25 PC138US, USLC-8...
SEN02469-01 40 Troubleshooting Method of using troubleshooting chart The troubleshooting chart consists of the "questions", "check items", "causes", and "troubleshooting" blocks. The questions and check items are used to pinpoint high probability causes by simple inspection or from phenomena without using troubleshooting tools. Next, troubleshooting tools or direct inspection are applied to check the narrowed causes in order from the most probable one to make final confirmation according to the troubleshooting procedure.
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SEN02469-01 40 Troubleshooting <Example of troubleshooting> Exhaust gas is black Let us assume that a trouble of "Exhaust gas is black" occurred and we checked the [Questions] and [Check items] and found the following 3 items to be the causal symptoms; [Exhaust gas slowly became black], [Power slowly became weaker], and [Dust indicator is lighting red].
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40 Troubleshooting SEN02469-01 There is a causal relationship between 3 items in the [Questions] and [Check items] sections and 5 items in the [Causes] section. The method of pinpointing the "cause" from the causal relationship and approaching the "troubleshooting" is explained according to Step 1 –...
SEN02469-01 40 Troubleshooting S-1 Starting performance is poor General causes why starting performance is poor Causes Defective electrical system Insufficient supply of fuel Insufficient intake of air Improper selection of fuel a The common rail fuel injection system (CRI) controls the fuel injection timing electrically.
40 Troubleshooting SEN02469-01 S-2 Engine does not start a) Engine does not turn Causes General causes why engine does not turn Seized parts inside engine o See “S-4 Engine stops during operations” Defective electrical system Confirm recent repair history Degree of use of machine Operated for long period Horn does not sound Condition of horn when...
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SEN02469-01 40 Troubleshooting b) Engine turns but no exhaust smoke comes out Causes General causes why engine turns but no exhaust smoke comes Fuel is not being supplied Supply of fuel is extremely small Improper selection of fuel (particularly in winter) Confirm recent repair history Degree of use of machine Operated for long period...
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40 Troubleshooting SEN02469-01 c) Exhaust smoke comes out but engine does not start Causes (fuel is being injected) General causes why exhaust smoke comes out but engine does not start Lack of rotating force due to defective electrical system Insufficient supply of fuel Insufficient intake of air Improper selection of fuel Confirm recent repair history...
SEN02469-01 40 Troubleshooting S-3 Engine does not pick up smoothly General causes why engine does not pick up smoothly Causes Insufficient intake of air Insufficient supply of fuel Defective condition of fuel injection Improper selection of fuel Controller is controlling in derate mode (limiting injection rate (output) because of an error in electrical system) Confirm recent repair history Degree of use of machine...
40 Troubleshooting SEN02469-01 S-4 Engine stops during operations General causes why engine stops during opera- Causes tions Internal parts of engine seized Insufficient supply of fuel There is overheating Problem in drive devices on applicable machine side o Carry out troubleshooting for devices on applicable machine Confirm recent repair history Degree of use of machine...
SEN02469-01 40 Troubleshooting S-5 Engine does not rotate smoothly General causes why engine does not rotate smoothly Causes Air in fuel system Defective speed sensor (Error at degree that it is not indicated) Confirm recent repair history Degree of use of machine Operated for long period Occurs at a certain speed range Q Q Q Q Q...
40 Troubleshooting SEN02469-01 S-6 Engine lacks output (or lacks power) General causes why engine lacks output Causes Insufficient intake of air Insufficient supply of fuel Defective condition of fuel injection Improper selection of fuel There is overheating o See “S-14 Coolant temperature becomes too high (Overheating)“...
SEN02469-01 40 Troubleshooting S-7 Exhaust smoke is black (incomplete combustion) General causes why exhaust smoke is black Causes Insufficient intake of air Defective condition of fuel injection Improper selection of fuel There is overheating o See “S-14 Coolant temperature becomes too high (Overheating)“...
40 Troubleshooting SEN02469-01 S-8 Oil consumption is excessive (or exhaust smoke is blue) General causes why oil consumption is excessive Causes Abnormal consumption of oil Long-time operation of engine at low idle or high idle (Do not run engine at idle for more than 20 minutes continuously) External leakage of oil Wear of pats in lubrication system...
SEN02469-01 40 Troubleshooting S-9 Oil becomes contaminated quickly General causes why oil becomes contaminated quickly Causes Entry of exhaust gas into oil due to internal wear Clogging of lubrication passage Use of improper fuel Use of improper oil Operation under excessive load Confirm recent repair history E E E Degree of use of machine...
40 Troubleshooting SEN02469-01 S-10 Fuel consumption is excessive General causes why fuel consumption is excessive Causes Leakage of fuel Defective condition of fuel injection (fuel pressure, injection timing) Excessive injection of fuel Confirm recent repair history Degree of use of machine Operated for long period Q Q Q More than for other machines of same model...
SEN02469-01 40 Troubleshooting S-11 Oil is in coolant (or coolant spurts back or coolant level goes down) General causes why oil is in coolant Causes Internal leakage in lubrication system Internal leakage in cooling system Confirm recent repair history Degree of use of machine Operated for long period Suddenly rose Oil level...
40 Troubleshooting SEN02469-01 S-12 Oil pressure drops General causes why oil pressure drops Causes Leakage, clogging, wear or lubrication system Defective oil pressure control Improper selection of fuel (improper viscosity) Deterioration of oil due to overheating Confirm recent repair history Degree of use of machine Operated for long period Oil pressure monitor indicates low oil pressure...
SEN02469-01 40 Troubleshooting S-13 Oil level rises (Entry of coolant or fuel) General causes why oil level rises Causes Coolant in oil (milky) Fuel in oil (smells diluted diesel fuel) a If oil is in coolant, carry out troubleshooting for “S-11 Oil is in coolant” Confirm recent repair history Degree of use of machine Operated for long period...
40 Troubleshooting SEN02469-01 S-14 Coolant temperature becomes too high (overheating) General causes why coolant temperature becomes too high Causes Lack of cooling air (deformation, damage of fan) Drop in heat dissipation efficiency Problem in coolant circulation system Confirm recent repair history Degree of use of machine Operated for long period Sudden overheated...
SEN02469-01 40 Troubleshooting S-15 Abnormal noise is made General causes why abnormal noise is made Causes Abnormality due to defective parts Abnormal combustion Air sucked in from intake system a Judge if the noise is an internal noise or an external noise before starting troubleshooting.
40 Troubleshooting SEN02469-01 S-16 Vibration is excessive General causes why vibration is excessive Causes Defective parts (abnormal wear, breakage) Misalignment between engine and chassis Abnormal combustion a If abnormal noise is made and vibration is excessive, carry out trouble- shooting for “S-15 Abnormal noise is made”, too. Confirm recent repair history Degree of use of machine Operated for long period...
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SEN02709-00 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly1 General information on disassembly and assembly How to read this manual ..........................2 List of adhesives ............................. 4 Special tool list ..............................7 Sketche of special tool ...........................11 PC138US, USLC-8...
* *** **** : Type of coating material means that they can not be supplied : Tightening torque from Komatsu in Japan (i.e. locally : Quantity of oil or coolant to be added made parts ). Sketches of special tools...
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Sketches of special tools means that they can not be supplied Various special tools are illustrated for the con- from Komatsu in Japan (i.e. locally venience of local manufacture. made parts ). a General tools that are necessary for dis- assembly and assembly are described as [1], [2]•••etc.
The recommended coating materials such as adhesives, gasket sealants, and greases used for disas- sembly and assembly are listed below. a For coating materials not listed below, use the equivalent of products shown in this list. Cate- Komatsu Part No. Q'ty Container...
Page 781
50 Disassembly and assembly SEN02709-00 Cate- Komatsu Part No. Q'ty Container Main features and applications gory code • To be sed as lubricant (anti squeaking) for slid- LM-G 09940-00051 60 g ing part. • To be used for press fit, shrink fit and prevent- ing scratching or seizure of thread.
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SEN02709-00 50 Disassembly and assembly Cate- Komatsu Part No. Q'ty Container Main features and applications gory code • "S" and "W" are used as glass adhesive Sunstar pen- compound in high temperature (April - guin seal 580 Polyethylene October) and in low temperature (October...
50 Disassembly and assembly SEN02709-00 Special tool list Tools with part number 79 QQQQ cannot be supplied (they are items to be locally manufactured). Necessity ..Cannot be substituted, must always be installed (used) ..Extremely useful if available or, can be substituted with commercially available part.
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SEN02709-00 50 Disassembly and assembly Sym- Component Part No. Part Name Nature of work, remarks 791-675-1510 Installer Application of floating seal 791-600-2001 Compressor (A) 791-685-8006 Compressor (B) 791-635-3160 Extension Compression of spring 790-201-2770 • Spacer Cylinder 790-101-1600 (686 kN {70 ton}) Disassembly, assembly 790-101-1102 Pump...
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50 Disassembly and assembly SEN02709-00 Sym- Component Part No. Part Name Nature of work, remarks 790-502-1003 Repair stand Disassembly, assembly of cyl- inder 790-101-1102 Pump 790-102-4300 Wrench assembly Removal, installation of piston 790-201-4310 790-201-1702 Push tool (Kit) 790-201-1791 • Push tool Press fit of bucket cylinder roll bushings 790-101-5021...
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SEN02709-00 50 Disassembly and assembly Sym- Component Part No. Part Name Nature of work, remarks 799-703-1200 Service tool (Kit) Vacuum pump 799-703-1100 Floor frame assembly (100V) airconditioner com- pressor assembly air- Vacuum pump Charging of air-conditioning 799-703-1111 conditioner condenser (220V) assembly aircondi- Vacuum pump tioner unit assembly...
50 Disassembly and assembly SEN02709-00 Sketche of special tool Note: Komatsu cannot accept any responsibility for special tools manufactured according to these sketches. F6 Push tool a Unless otherwise specified, there shall be on burrs or flushes at the corner.
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SEN02710-00 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly Engine and cooling system Removal and installation of fuel supply pump assembly ................2 Removal and installation of fuel injector assembly ..................4 Removal and installation of front oil seal ......................
SEN02710-00 50 Disassembly and assembly Removal and installation of fuel Loosen sleeve nuts (12) and (13) and remove high pressure pipe (14). [*2] supply pump assembly Remove the pin and disconnect spill hose (15). Removal Remove joint bolts (16), (17) and (18) and Disconnect the negative (–) terminal of the remove fuel tubes (19) and (20).
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Never bens a high-pressure pipe for the convenience sake. The clamp used for fixing a high-pressure pipe must be a genuine Komatsu part and it must be tightened to the specified torque. Be sure to install the boot to the sleeve nut Remove 3 nuts (26) and remove supply after installing the high-pressure pipe.
SEN02710-00 50 Disassembly and assembly Removal and installation of fuel Removal of the high-pressure pipe a The following indicates the removal of injector assembly injector assembly of cylinder No. 1 for example. Removal Remove clamp (5) from the high-pressure Disconnect the negative (–) terminal of the pipe.
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Never bend a high-pressure pipe for the convenience sake. The clamp used for fixing a high-pressure pipe must be a genuine Komatsu part and it must be tightened to the specified torque. Be sure to install the boot to the sleeve nut after installing the high-pressure hose.
Page 794
SEN02710-00 50 Disassembly and assembly [*4] When reusing injector, always replace Oring (15) and gasket (16) with new ones. PC138US, USLC-8...
50 Disassembly and assembly SEN02710-00 Removal and installation of front Loosen fan belt adjust bolt (3) and remove fan belt (4). [*1] oil seal Remove engine speed sensor connector (5). Special tools Remove speed sensor mounting bolt (6) and remove speed sensor (7). [*2] Sym- Part No.
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SEN02710-00 50 Disassembly and assembly Installation Use tool A1 (outside diameter of 80 mm) to press front oil seal (10) in gear case (11). Check the crankshaft end corner and the oil seal lip sliding surface for flaws, burrs, scars, or rust, before installing the oil seal. Fill about 2 cc of grease to between the oil seal lips.
50 Disassembly and assembly SEN02710-00 Removal and installation of rear Temporarily lift flywheel (3). Remove 7 flywheel mounting bolts (4) oil seal except one. [*2] Special tools Sym- Part No. Part name Seal puller assem- 795-931-1100 790-101-5401 • Push tool (kit) 790-101-5431 •...
Page 798
SEN02710-00 50 Disassembly and assembly Removal of the rear oil seal Installation Screw the tip of tool A4 into the metal ring Rear oil seal mounting procedure of seal (5) and pull it out with the impact of Use tool A3 (outside diameter of 120 mm) to a slide hammer [1].
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50 Disassembly and assembly SEN02710-00 [*3] Measuring radial runout of flywheel Install dial gauge [2] to the flywheel hous- ing. Set the probe of the dial gauge at right angles to the spigot joint (a) or the outer periphery of the flywheel. Rotate the crank shaft one full turn and measure the difference of the maximum values of runout of the needle.
SEN02710-00 50 Disassembly and assembly Removal and installation of Disconnect aftercooler hose (11) from the air intake connector (12) side. cylinder head assembly Removal Disconnect the negative (–) terminal of the battery beforehand. Remove the counterweight assembly, referring to "Removal of counterweight assembly." Removal of engine controller frame assem- Remove engine controller mounting bolts (1) from the upper frame (2).
Page 801
50 Disassembly and assembly SEN02710-00 Disconnection of wiring Remove 8 air intake manifold mounting Disconnect heater wiring E01 (20). bolts (37) and remove air intake manifold Disconnect injector wiring CN1 to CN4 (38). [*7] (21). Disconnect boost pressure sensor con- nector PTIM (22).
Page 802
SEN02710-00 50 Disassembly and assembly Remove 2 clamp mounting bolts (44) and 13. Removal of turbocharger and exhaust man- remove clamp (45). [*10] ifold assembly Remove cover (52). Remove divider board (46). Remove rubber covers (47) and (48). Disconnect blowby tube (53). Remove 3 mounting nuts (54) and remove cylinder head cover (55).
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50 Disassembly and assembly SEN02710-00 Remove mounting bolts (56) and discon- 14. Removal of water pump nect turbocharger lubricant inlet port tube Disconnect coolant temperature sensor (57). [*12] connector TWTR (64). Remove 2 mounting bolts (58) and discon- Disconnect radiator upper hose (65), nect turbocharger lubricant return tube heater hoses (66) and (67) and radiator (59).
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SEN02710-00 50 Disassembly and assembly 15. Removal of rocker arm assembly Installation Loosing lock nut (74) and fully loosen Carry out the installation in the reverse order of adjustment screw (75). [*15] removal. a Loosen the air intake and exhaust adjustment screws on all cylinders.
Page 805
The clamp used for fixing a high-pressure Mounting face: pipe must be a genuine Komatsu part and it Gasket sealant (LG – 7) must be tightened to the specified torque. Be sure to install the boot to the sleeve nut [*8] [*9] after installing the high-pressure hose.
Page 806
SEN02710-00 50 Disassembly and assembly Install the exhaust manifold and tighten the mounting bolt. Exhaust manifold mounting bolt: 9.8 – 12.7 Nm {1.0 – 1.3 kgm} [*14] a One (1) of the water pump mounting bolts is tightened together with the alternator mounting bracket.
50 Disassembly and assembly SEN02710-00 Removal and installation of Open covers (9) and (10). radiator assembly Removal Stop the machine on a level place and lower it to the ground. Stop the engine and set the lock lever to locked position. Disconnect the negative (–) terminal of the battery beforehand.
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SEN02710-00 50 Disassembly and assembly Installation Carry out the installation in the reverse order of removal. [*1] Coolant: 12.4 l l l l [*2] [*3] Radiator hose clamp bolt: (Both upper and lower hoses) 8.8 ± 0.5 Nm {0.9 ± 0.05 kgm} [*4] a When installing the radiator assembly, align the convex portion (a) on the bottom of the...
50 Disassembly and assembly SEN02710-00 Removal and installation of Loosen 2 clamps (6) and disconnect the air aftercooler upper hose (7). aftercooler assembly Remove 2 mounting bolts (8) and remove plate Removal (9). Disconnect the negative (–) terminal of the battery beforehand.
Page 810
SEN02710-00 50 Disassembly and assembly Installation Carry out the installation in the reverse order of removal. [*1] a Take care not to damage sponge on the sides when installing the aftercooler. a When installing the radiator assembly, align the convex portion (a) on the bottom of the air aftercooler with the concave portion (b) on the machine.
50 Disassembly and assembly SEN02710-00 a When using tool D to stop oil, remove the Removal and installation of work hydraulic oil tank strainer in advance. equipment oil cooler assembly Special tools Sym- Part No. Part name 796-460-1210 Oil stopper 795-799-1131 Adapter Removal...
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SEN02710-00 50 Disassembly and assembly Remove air cleaner (5). 11. Pull out oil cooler assembly (11). [*2] Remove connector (6). Remove air cleaner hose clamp (7). Remove 2 hose mounting bolts (8) and discon- nect oil cooler upper hose (9). 10.
Page 813
50 Disassembly and assembly SEN02710-00 Installation Carry out the installation in the reverse order of removal. [*1] Hydraulic oil drain plug (13): 58.8 – 78.4 Nm {6 – 8 kgm} Target: 68.6 Nm {7 kgm} Hydraulic tank: 69 l l l l (Specified capacity: 120 l l l l ) PC138US, USLC-8...
SEN02710-00 50 Disassembly and assembly Removal and installation of Open fuel drain valve (3) to drain fuel. engine and work equipment pump assembly Special tools Sym- Part No. Part name 796-460-1210 Oil stopper 795-799-1131 Adapter Loosen hydraulic oil drain plug (4) to drain the Removal work equipment oil.
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50 Disassembly and assembly SEN02710-00 Remove covers (5), (6) and (7). Remove frame mounting bolts (20), (21) and (22). Open covers (8) and (9). Lift frame cover assembly (23) and remove it. Remove counterweight, referring "Removal and Installation of Counterweight." Removal of frame cover assembly Temporarily lift the frame cover assembly.
Page 816
SEN02710-00 50 Disassembly and assembly Remove adjustment and mounting bolts (31) and remove air conditioner compres- Disconnect starting motor wiring terminals sor (33). (42) and (42a). [*7] a Do not disconnect the air conditioner Remove wiring bracket mounting bolt (43) hoses.
Page 817
50 Disassembly and assembly SEN02710-00 13. Remove 4 bracket mounting bolts (51) and dis- Disconnect 6 hoses (56) to (61). connect engine oil filter and bracket assembly (52). a Tie the assembly with a string to keep it out of the way. Remove 4 bolts (62) and disconnect suc- tion tube (63).
Page 818
SEN02710-00 50 Disassembly and assembly 16. Lift engine and work equipment pump assem- Installation bly (65) and remove it. Carry out the installation in the reverse order of Engine and work equipment pump removal. assembly: 470 kg [*1] Coolant: 12.4 l l l l [*2] Hydraulic oil drain plug (13): 58.8 –...
50 Disassembly and assembly SEN02710-00 Removal and installation of fuel Removal of exterior parts Remove hand rail (7). tank assembly Remove covers (8) to (11). Removal Stop the machine on a level place and lower it to the ground. Stop the engine and set the lock lever to locked position.
Page 820
SEN02710-00 50 Disassembly and assembly Disconnect hoses (15) and (16). Installation Remove 4 fuel tank front mounting bolts Carry out the installation in the reverse order of (17). removal. [*1] Fuel tank mounting bolt: liquid adhesive (LT–2) Fuel tank mounting bolt: 235 –...
Page 821
50 Disassembly and assembly SEN02710-00 PC138US, USLC-8...
Page 823
SEN02711-00 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly Power train Removal and installation of travel motor and final drive assembly ..............2 Removal and installation of swing motor and swing machinery assembly ............. 4 Disassembly and assembly of swing machinery assembly ................
SEN02711-00 50 Disassembly and assembly Removal and installation of travel motor and final drive assembly Removal Remove track shoe assembly. For details, see "Removal of track shoe assembly". Lower the work equipment completely to the ground and stop the engine. Then loosen the oil filler cap slowly to release the pressure inside the hydraulic tank.
Page 825
50 Disassembly and assembly SEN02711-00 Installation Carry out installation in the reverse order to removal. [*1] Thread of travel motor mounting bolt : Thread tightener (LT-2) Sprocket mounting bolt : 323.6 – 362.8 Nm {33 – 37 kgm} [*2] Thread of travel motor and final drive assembly mounting bolt : Thread tightener (LT-2) Travel motor and final drive assembly...
SEN02711-00 50 Disassembly and assembly Removal and installation of swing Remove mounting bolt (9). motor and swing machinery Remove swing motor and swing machinery assembly assembly (10) from the machine using forcing screw [1]. Removal Park the machine on a level place and lower the work equipment stably to the ground.
Page 827
50 Disassembly and assembly SEN02711-00 Installation Carry out the installation in the reverse order of removal. Refilling oil (Hydraulic tank) a Fill oil up to the specified level, start the engine to circulate oil in the pipe and check the oil level again. Bleeding air a Bleed air from the piping, referring to "Bleeding air from each part"...
SEN02711-00 50 Disassembly and assembly Disassembly and assembly of swing machinery assembly Special tools Sym- Part No. Part name 790-201-2750 Spacer 790-101-5201 Push puller (Kit) 790-101-2510 • Block Disconnect swing motor assembly (4) 790-101-2550 • Leg using forcing screw [1]. 790-101-2560 •...
Page 829
50 Disassembly and assembly SEN02711-00 ub-disassembly of carrier No. 1 and sun Sub-disassembly of carrier No. 2 assem- gear No. 2 assembly bly. Remove snap ring (7) and remove Press pin (20) in and punch out shaft thrust washer (8), gear (9), bearing (21) from carrier (22).
Page 830
SEN02711-00 50 Disassembly and assembly Shaft assembly Use puller [4] to remove bearing outer Set the shaft and case assembly (30) to races (37) and (38) from case (36). block [2], and remove shaft assembly (31) with the press using push tool [3]. Remove bearing (29).
Page 831
50 Disassembly and assembly SEN02711-00 Assembly Install 2-piece collar (28). Screw in bolt (12 mm, P=1.75) to the Bearing outer race case. Using push-pull scale [5] to measure Use push tool F3 to press outer races (37) and the tangential force in the direction of rota- (38) to case (36).
Page 832
SEN02711-00 50 Disassembly and assembly Carrier No. 2 assembly Sub-disassembly of carrier No. 2 assem- Assemble bearing (25) to gear (24). Install thrust washer (23) and (26) and set gear assembly to carrier (22). Ring gear Install O-ring (40) to the shaft and case assem- bly, and install ring gear (17).
Page 833
50 Disassembly and assembly SEN02711-00 Install thrust washer (11), bearing Swing motor assembly (10), gear (9) and thrust washer (8), Install swing motor assembly (4). and install snap ring (7). Install 15 swing motor mounting bolts (3). a Use new snap ring. Swing motor mounting bolt: a ?hen installing the snap ring, do 110.3 ±...
SEN02711-00 50 Disassembly and assembly Removal and installation of Installation swing circle assembly Installation is performed in the opposite way to removal. Removal Gradually loosen the hydraulic oil tank cap [*1] to bleed the air from the tank after ground- Swing circle mounting bolt: ing the work equipment and stopping the Liquefied adhesive (LT-2)
Page 835
50 Disassembly and assembly SEN02711-00 PC138US, USLC-8...
Page 837
SEN02712-00 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly Undercarriage and frame Disassembly and assembly of track roller....................... 2 Disassembly and assembly of idler assembly ....................5 Disassembly and assembly of recoil spring ....................8 Removal and installation of of track shoe assembly ..................11 Removal and installation of sprocket ......................
SEN02712-00 50 Disassembly and assembly Disassembly and assembly of Pull out roller (4) from shaft (5). a It is filled with 75 – 85 cc of oil, so drain the track roller oil at this point or lay a cloth to prevent the area from becoming dirty.
Page 839
50 Disassembly and assembly SEN02712-00 Assembly Turn over roller (4) and shaft (5) assembly. Using push tool [1], press fit bushings (9) and Using tool M1, install floating seal (3) to collar (10) to roller (4). (2). a For details of the precautions when install- Assemble collar (8) to shaft (5).
Page 840
SEN02712-00 50 Disassembly and assembly 10. Using tool M2, fill track roller assembly with oil, then tighten plug (11). Track roller oil: 75 – 85 cc (EO30-CD) PC138US, USLC-8...
50 Disassembly and assembly SEN02712-00 Disassembly and assembly of idler assembly Special tools Sym- Part No. Part name 791-675-1510 Installer Disassembly Remove dowel pin (1), then remove support Remove dowel pin (8), then remove support (2). (7) from shaft (5). Remove bushings (9) and (10) from idler (4).
Page 842
SEN02712-00 50 Disassembly and assembly Assembly Assemble shaft (5) and support assembly (7) to idler (4). Press fit bushings (9) and (10) to idler (4). Add oil between shaft (5) and idler (4). Fit O-ring and install support (7) to shaft (5) with dowel pin (8).
Page 843
50 Disassembly and assembly SEN02712-00 Install O-ring, then install support (2) with dowel pin (1). PC138US, USLC-8...
SEN02712-00 50 Disassembly and assembly Disassembly and assembly of recoil spring Special tools Sym- Part No. Part name 791-600-2001 Compressor (A) 791-685-8006 Compressor (B) 791-635-3160 Extension 790-201-2770 • Spacer Cylinder 790-101-1600 (686 kN {70 ton}) 790-101-1102 Pump Disassembly Remove lock plate (1), then remove seat (2) and valve (3).
Page 845
50 Disassembly and assembly SEN02712-00 Apply hydraulic pressure slowly to com- press spring, then remove nut (6). a Compress the spring to a point where the nut becomes loose. a Release the hydraulic pressure slowly to remove the spring tension. Remove pilot (8), and spring (7).
Page 846
SEN02712-00 50 Disassembly and assembly Assembly Assembly of yoke piston assembly Assemble wear ring (16) to yoke piston (13). Assemble U-packing (15) and secure with snap ring (14). Assembly of recoil spring assembly Using tool [1], press fit bush (12) to cylin- der (9).
50 Disassembly and assembly SEN02712-00 Removal and installation of of Move machine forward so that position of mas- ter pin is at front of idler, and set block [1] in track shoe assembly position. Special tools Using tool R, pull out master pin. [*2] Remove tool R, pull out temporary pin, and Sym- Part No.
Page 848
SEN02712-00 50 Disassembly and assembly Installation [*1] a Adjust the track tension. For details, see Testing and adjusting, "Testing and adjusting track tension". [*2] a Use tool R and press fit the master pin so that the protrusion of the master pin is dimension (a).
50 Disassembly and assembly SEN02712-00 Removal and installation of Installation Carry out installation in the reverse order to sprocket removal. Removal [*1] Expand the track shoe assembly. For details, Threads of sprocket mounting bolt: see Expansion of track shoe assembly. Adhesive (LT-2) Sprocket mounting bolt: Swing the work equipment by 90°...
SEN02712-00 50 Disassembly and assembly Removal and installation of Disconnect drain hose (8) and hoses (9) and (10) between control valve and left travel motor revolving frame assembly from center swivel joint. Removal Disconnect hoses (11) and (12) between con- Disconnect the negative (–) terminal of the trol valve and right travel motor.
Page 851
50 Disassembly and assembly SEN02712-00 12. Lift revolving frame assembly (16) to loosen Installation remaining bolts (15). Installation is performed in the opposite way to a Carefully remove the remaining bolts by removal. balancing them using the crane. a Carefully lift and remove them to prevent [*1] them from coming in contact with the cen- Surface inside bushing during pin assembly:...
SEN02712-00 50 Disassembly and assembly Removal and installation of Demporarily lift the counterweight, and remove 3 mounting bolts (9). [*1] counterweight assembly (Machine without add-on weight) Removal Stop the machine on a level ground, stop the engine, and lower the work equipment to the ground.
Page 853
50 Disassembly and assembly SEN02712-00 Installation Carry out installation in the reverse order to removal. [*1] Counterweight mounting bolt: Adhesive (LT-2) Counterweight mounting bolt: 3,430 – 4,212 Nm {350 – 430 kgm} Target: 3,626 Nm {370 kgm} PC138US, USLC-8...
SEN02712-00 50 Disassembly and assembly Removal and installation of Sling the counterweight and remove 3 mount- ing bolts (5). [*2] counterweight assembly (Machine with add-on weight) Removal Stop the machine on a level ground, stop the engine, and lower the work equipment to the ground.
Page 855
50 Disassembly and assembly SEN02712-00 Installation Carry out installation in the reverse order to removal. [*1] Installation procedure for add-on weight Put faces (X) and (Y) to the insert boss of the counterweight. Install top bolt (2) and tighten it lightly. Add-on weight mounting bolt: Adhesive (LT-2) Adjust clearance (a) to 10 ±...
Page 857
SEN02713-00 HYDRAULIC EXCAVATOR PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly Hydraulic system Removal and installation of center swivel joint assembly ................2 Disassembly and assembly of center swivel joint assembly................4 Removal and installation of hydraulic tank assembly..................
SEN02713-00 50 Disassembly and assembly Removal and installation of center swivel joint assembly Removal Gradually loosen the hydraulic oil tank cap to bleed the internal air after completely grounding the work equipment and stop- ping the engine. Disconnect the negative (–) terminal of the battery.
Page 859
50 Disassembly and assembly SEN02713-00 Installation Installation is performed in the opposite way to removal. [*1] Mounting bolt screw: Liquefied adhesive (LT-2) Mounting bolt: 98.1 – 123.0 Nm {10.0 – 12.5 kgm} Bleeding air q q q q Bleed air from the swing motor. For details, see Testing and adjusting, "Bleeding air from each part".
SEN02713-00 50 Disassembly and assembly Disassembly and assembly of center swivel joint assembly Special tools Sym- Part No. Part name 790-101-2501 Push puller 790-101-2510 • Block 790-101-2520 • Screw 790-101-2540 • Washer Assembly 791-112-1180 Fit slipper seals (7) and O-rings (6) to swivel •...
50 Disassembly and assembly SEN02713-00 a When using tool D to stop oil, remove the Removal and installation of hydraulic oil tank strainer in advance. hydraulic tank assembly Special tools Sym- Part No. Part name 796-460-1210 Oil Stopper 795-799-1131 Adapter Removal Park the machine on a level place and lower Removal of exterior parts...
Page 862
SEN02713-00 50 Disassembly and assembly Remove engine oil filter bracket (9). Removal of hydraulic oil tank mounting bracket a Move the filter assembly close to the and mounting bolts. engine. Remove fuel tank rear mounting brackets Disconnect hose (10) from radiator. (23).
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50 Disassembly and assembly SEN02713-00 Lift and remove hydraulic oil tank assembly Installation (27). Carry out the installation in the reverse order of Hydraulic oil tank assembly: 95 kg removal. [*1] Drain plug (1): 58.8 – 78.4 Nm {6 – 8kgm} Target: 68.6 Nm {7 kgm} Hydraulic oil tank: 69 l l l l (Capacity: 120 l l l l )
SEN02713-00 50 Disassembly and assembly a When using tool D to stop oil, remove the Removal and installation of hydraulic oil tank strainer in advance. hydraulic pump assembly Special tools Sym- Part No. Part name 796-460-1210 Oil Stopper 795-799-1131 Adapter Removal Park the machine on a level place and lower Remove covers (2) and (3).
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50 Disassembly and assembly SEN02713-00 Disconnect damper case oil filler hose(7). Disconnect 6 hoses(17) to (22). a Record the installed position of respec- Removal of muffler assembly tive hoses. Remove divider boards (8) and rubber covers (9) and (10). Disconnection hydraulic pump Temporarily lift the pump (23) and remove Remove muffler drain tube (11).
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SEN02713-00 50 Disassembly and assembly 10. Removal procedures of work equipment Install wire rope [2] to the work equipment pump pump from outside the counterweight. a Apply rubber plates or cloth [3] to the Remove work equipment pump by pulling it toward the front according to the following pro- counterweight to prevent it from being cedures.
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50 Disassembly and assembly SEN02713-00 Disconnect chain block from the work Installation equipment pump, shift the work equip- Carry out the installation in the reverse order of ment pump (23) forward to the front and removal. remove it. PC138US, USLC-8...
SEN02713-00 50 Disassembly and assembly a When using tool D to stop oil, remove the Removal and installation of hydraulic tank strainer in advance. control valve assembly Special tools Sym- Part No. Part name 796-460-1210 Oil Stopper 795-799-1131 Adapter Removal Park the machine on a level place and lower Removal of exterior parts the work equipment stably to the ground.
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SEN02713-00 50 Disassembly and assembly Disconnect hoses (36) to (39). (Index No. , Color band , Hose Name) (36); (Orange) Arm dump (37); (White) Swing left (38); (Red) Bucket dump (39); (Red-Yellow) Boom raise Disconnection of control valve connectors and hoses (Connectors) Disconnect connectors (40) to (42) from right side of control valve.
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50 Disassembly and assembly SEN02713-00 (78); (Yellow- Black) (79); (Yellow- Green) (80); (Yellow- Brown) (81); (Yellow- Orange) (82); (White) (83); (Brown) Disconnect 5 hoses (63) to (67) left side (operator cab side) of control valve. (63); (–) (64); (Red- Red) (65);...
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SEN02713-00 50 Disassembly and assembly Remove bracket mounting bolt (87) and Installation r emov e multi - val ve as sem bly m ounti ng Carry out the installation in the reverse order of bracket (88). removal. 10. Loosen 4 control valve mounting bolt(89) and lift and remove control valve assembly (90).
50 Disassembly and assembly SEN02713-00 Disassembly and assembly of control valve assembly Assembly PC138US, USLC-8...
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SEN02713-00 50 Disassembly and assembly The appearance and section of only the 8-spool valve (blade + service valve) are shown here. A1 : To swing motor LS3 : LS3 pressure pickup port A2 : To blade cylinder bottom : From swing left PPC valve A3 : To left travel motor PA2 : From blade lower PPC valve A4 : To right travel motor...
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50 Disassembly and assembly SEN02713-00 a In this section, only the precautions for assem- bling the control valve assembly are described. Before assembling the parts, apply engine oil to their sliding surfaces. Mating face: Liquid sealant (Sealend 242 or equivalent) a The tightening torque of the parts and the pre- cautions are shown below (in random order).
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SEN02713-00 50 Disassembly and assembly PC138US, USLC-8...
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50 Disassembly and assembly SEN02713-00 PC138US, USLC-8...
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SEN02713-00 50 Disassembly and assembly PC138US, USLC-8...
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50 Disassembly and assembly SEN02713-00 PC138US, USLC-8...
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SEN02713-00 50 Disassembly and assembly PC138US, USLC-8...
50 Disassembly and assembly SEN02713-00 Disassembly and assembly of work equipment PPC valve assembly (For boom, bucket, arm, swing control) Disassembly Remove nut (13), then remove disc (12), nut (11) and boot (15). Remove bolts, then remove plate (5). a Do not remove joint (10) unless it is to be replaced.
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SEN02713-00 50 Disassembly and assembly Assembly a When assembling, clean and inspect the parts closely and take care fully so that dirt, rust, flaw, etc. will not cause a trouble. When installing plug (2) to body (1), take care that its tip will not enter the hole of the body 20 mm in diameter.
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50 Disassembly and assembly SEN02713-00 When installing joint (10) to body (1), apply Installation of disc (12) LOCTITE as shown below. Install disc (12) so that each bolt (9) will be When installing the joint, apply 1 drop the center of each side of disc (12) and (approx.
SEN02713-00 50 Disassembly and assembly Disassembly and assembly of travel PPC valve assembly Disassembly Remove screw (13) to remove lever (9). Remove pin (5) from plate (8), and remove the plate (8) from the lever (9). Remove mounting bolt (15) to remove case shaft assembly (17).
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50 Disassembly and assembly SEN02713-00 Assembly a When assembling, clean and inspect the parts closely and take care fully so that dirt, rust, flaw, etc. will not cause a trouble. When installing piston (1), apply grease (G2- LI) to its outside and the inside of the body hole.
SEN02713-00 50 Disassembly and assembly Disassembly and assembly of Disassembly a This section explains how to disassemble and hydraulic cylinder assembly assemble the boom, arm, bucket and blade cylinders. For how to disassemble and assem- Special tools ble the offset cylinder, refer to "Disassembly and assembly of offset cylinder assembly".
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50 Disassembly and assembly SEN02713-00 Remove piston assembly lock screw Remove the head assembly (7). (3). Screw size M12 x 1.75 pitch: Boom, arm and blade M10 x 1.5 pitch: Bucket Remove cap (8) to remove eleven balls (9) and cushion plunger (10). For the arm cylinder only.
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SEN02713-00 50 Disassembly and assembly Disassembly of cylinder head assembly Assembly Remove O-ring and backup ring (15). a Be careful not to damage the packing, the dust Remove snap ring (16), then remove dust seal, the O-ring or the like seal (17).
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50 Disassembly and assembly SEN02713-00 Sub-assembly of piston assembly Assemble head assembly (7). Expand piston ring (13) using tool (U5). Fit O-ring and backup ring to collar (6), a Set the piston ring on tool (U5) and and assemble. expand it by rotating the handle eight Arm cylinder and boom cylinder.
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SEN02713-00 50 Disassembly and assembly Drill a hole for mounting screw (3). a Engage the drill with the screw V- shaped grooves of piston (4) and rod (2) for horizontal processing. a Process bottom cushion- equipped cylinder (arm cylinder) on other part than the cap hole (8).
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50 Disassembly and assembly SEN02713-00 Engage piston rod assembly (2) Seal: Grease (G2-LI) a Set the ring abutment joint horizon- tally and align the axes of the piston rod assembly and the cylinder tube to insert them. a After insertion, make sure that the ring is not damaged or dropped and completely push the piston rod.
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SEN02714-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly1 Work equipment Body Removal and installation of work equipment assembly .................. 2 PC138US, USLC-8...
SEN02714-00 50 Disassembly and assembly Removal and installation of work Disconnect working lamp wiring connector (6) and clamp (7). equipment assembly Remove guard (8). Special tools Disconnect hoses (9) (Arm cylinder bottom), (10) (Bucket cylinder bottom), (11) (Arm cylin- Sym- Part No.
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50 Disassembly and assembly SEN02714-00 12. Set tool V to boom foot pin (19). Installation Carry out installation in the reverse order to removal. [*1] a When tightening the locknut, tighten so that the clearance (a) between the plate and nut is 0.5 –...
Page 898
SEN02714-00 50 Disassembly and assembly [*3] Inside surface of bushing when assembling pin : Molybdenum disulphide lubricant (LM-P) Grease after assembling pin : Grease (LM-G) When aligning the position of the pin hole, never insert your fingers in the pin hole. a Adjust the shim thickness so that clearance (c) between boom (23) and bracket (24) is less than 0.5 mm.
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50 Disassembly and assembly SEN02714-00 PC138US, USLC-8...
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SEN02715-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly1 Cab and its attachments Removal and installation of operator cab assembly ..................2 Removal and installation of operator's cab glass (stuck glass)............... 4 Removal and installation of front window assembly ..................
SEN02715-00 50 Disassembly and assembly Removal and installation of Remove cover (11). operator cab assembly Removal Park the machine on a level place and lower the work equipment stably to the ground. Stop the engine and set the lock lever to locked position.
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50 Disassembly and assembly SEN02715-00 13. Removal of operator cab mounting bolts and 14. Lift and remove operator cab assembly (27). a Before removing the operator cap assem- nuts. bly, make sure that all wiring and piping Remove 6 mounting bolts (22b) (marked are disconnected.
SEN02715-00 50 Disassembly and assembly Removal and installation of operator's cab glass (stuck glass) Amoung the panes of window glass on the 4 ( 1 ): Right side window glass sides of the operator’s cab, 5 panes (1) – (5) ( 2 ): Left side rear window glass are stuck.
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50 Disassembly and assembly SEN02715-00 a If the window glass is broken finaly, it may be Special tools removed with knife [4] and a screwdriver. a Widening the cut with a screwdriver, cut the adhesive and both-sided adhesive tape with Sym- Part No.
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SEN02715-00 50 Disassembly and assembly Installation Using a knife and scraper [5], remove the remaining adhesive and both-sided adhesive tape from the metal sheets (glass sticking sur- faces) of the operator’s cab. a Remove the adhesive and both-sided adhesive tape to a degree that they will not affect adhesion of the new adhesive.
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50 Disassembly and assembly SEN02715-00 a As for right side window glass (1), Evenly apply paint primer to the surfaces to stick both-sided adhesive tapes and the apply the primer to only the periphery surfaces out of those surfaces on opera- of the glass to stick the both-sided tor’s cab (8) which will be coated with the adhesive tapes and the areas out of it...
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SEN02715-00 50 Disassembly and assembly a Parts to be coated with primer: Apply a When sticking both-sided adhesive tape the primer to the sticking surfaces of (7) around a frame, do not lap its finishing window glass (9) and all over dimen- end over the starting end but make clear- sion (d) which will be on both-sided ance e of about 5 mm between them.
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50 Disassembly and assembly SEN02715-00 Stick both-sided adhesive tape (7) for door Details of the sticking positions are as upper window glass (3) and lower window follows. glass (4) as shown in the figure. (h): Stick to inside end of right and left (The figure shows the door upper window front frames (17).
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SEN02715-00 50 Disassembly and assembly a When positioning front window glass Break aluminum seal (13) of the outlet of (5), set its horizontal and vertical posi- adhesive cartridge (12) and install the tions as shown below. nozzle. Part (m) (Right side): Project by "3.8 mm"...
Page 911
50 Disassembly and assembly SEN02715-00 Remove the release tape of the both- Install the window glass. sided adhesive tape on the glass side. Install window glass (9), matching it to the Apply adhesive (15) to the outside of both- lines of the positioning tapes drawn in step sided adhesive tape (7) of the operator’s a Sine the window glass cannot be cab.
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SEN02715-00 50 Disassembly and assembly a After installing front window glass (5), (The figure shows the operator's cab of PC200- install the center trim seal to its bot- tom. Then, apply caulking material all a r ou nd t he g la s s to fi ll par t ( U) between the glass and center trim seal.
50 Disassembly and assembly SEN02715-00 Removal and installation of front window assembly Lower the work equipment to the ground and stop the engine. a To replace the front window glass, the front window assembly must be removed from the operator’s cab. The procedure for removing and installing the front window assembly (front frame and front window glass) is explained below.
SEN02715-00 50 Disassembly and assembly Removal and installation of floor Remove lower cover (1). frame assembly Special tools Sym- Part No. Part name 799-703-1200 Service tool (Kit) Vacuum pump 799-703-1100 (100V) Vacuum pump 799-703-1111 (220V) Open the coolant drain valve (2) and drain Vacuum pump coolant.
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50 Disassembly and assembly SEN02715-00 Remove covers (111), (112) and (113). Disconnect wiring connectors (8) to (16) around the solenoid valves connected to wring (7). (8) : V01 (PPC basic pressure) (9) : V02 (Travel HI/LO) (10): V03 (Swing paring brake) (11) : V04 (Travel junction valve) (12): V05 (Merge-divider valve selection signal)
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SEN02715-00 50 Disassembly and assembly Disconnecting pressure switch and pressure Disconnection of control valve assembly wiring sensor connector wiring and hoses (R.H. side of control valve-inspection cover Disconnect wiring connectors (20) to (29) side-) connected to wiring (19). (20): P01 (Bucket dump switch) Disconnect hose (31) to the attachment.
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50 Disassembly and assembly SEN02715-00 (Operator cab side) Disconnect 8 hoses (47) to (54) from the oper- Disconnect wiring connectors (39) to (41). ation pattern select valve assembly. (Machine (39): P61 (Bucket dump switch) with the select valve) (40): P62 (Arm dump switch) (From the upper side of operator cab) (41): P63 (Boom raise switch) (47): Brown (Swing right)
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SEN02715-00 50 Disassembly and assembly Disconnect PPC drain hose (55). 12. Disconnect buzzer wiring connector (60). 13. Disconnect buzzer wiring clamp (61) and dis- connect the buzzer wiring. Disconnect wiring A13 (56) and A08 (57). a How to remove clamp (61) Hold a flat-head screwdriver [1] to section (a) and push it downward.
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50 Disassembly and assembly SEN02715-00 14. Remove operator cab assembly, referring to "Removal of operator cab assembly." 15. Disconnecting floor lower wiring and clamps Disconnect wiring and hose clamps (62) to (73). Disconnect air conditioner Hi-Lo pressure switch wiring connector (74). Disconnect air conditioner hoses (75) and (76).
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SEN02715-00 50 Disassembly and assembly Installation Disconnect grounding wire (81). Carry out the installation in the reverse order of removal. [*1] a Care must be exercised in the installation so that dusts, dirt or water may not enter the hose of the air conditioner circuit.
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50 Disassembly and assembly SEN02715-00 PC138US, USLC-8...
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SEN02716-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 50 Disassembly and assembly1 Electrical system Removal and installation of air compressor assembly ..................2 Removal and installation of air conditioner condenser ................... 3 Removal and installation of air compressor unit assembly ................
SEN02716-00 50 Disassembly and assembly Removal and installation of air Installation Carry out the installation in the reverse order of compressor assembly removal. Special tools [*1] Precautions when installing piping q q q q a Care must be exercised in the installation so Sym- Part No.
50 Disassembly and assembly SEN02716-00 Removal and installation of air Disconnect 2 hoses (3). a Put blind caps to prevent the entry of dirt conditioner condenser or water into hoses and compressor. Special tools Remove 4 bolts and remove condenser (4). Sym- Part No.
SEN02716-00 50 Disassembly and assembly Removal and installation of air Disconnect wiring connector (2) of the air con- ditioner high and low pressure switch. compressor unit assembly Disconnect air conditioner hoses (3) and (4). Special tools Disconnect heater hoses (5) and (6). Sym- Part No.
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50 Disassembly and assembly SEN02716-00 Remove cover (15). 14. Remove cover (23). 10. Remove cover (16). 15. Remove 3 cover mounting bolts (24) on the left and right. 11. Remove duct (17). 12. Remove covers (18) and (19). 16. Lift cover (25) using 3 forcing bolts [1]. 17.
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SEN02716-00 50 Disassembly and assembly Installation Carry out the installation in the reverse order of removal. [*1] Precautions when installing piping q q q q a Care must be exercised in the installation so that dusts, dirt or water may not enter the hose of the air conditioner circuit.
50 Disassembly and assembly SEN02716-00 Removal and installation of Disconnect connector (3) to (5). machine monitor assembly Remove 3 mounting bolts (6) and remove machine monitor assembly (7). Removal Disconnect the negative (–) terminal of the battery beforehand. Remove the 2 mounting bolts and cover (1). a One of the mounting bolts is installed inside the cap on the right of the daylight sensor.
SEN02716-00 50 Disassembly and assembly Removal and installation of pump Disconnect wiring (5) and (6). a Pull each connector lever (a) and (b) controller assembly inward. Removal Remove 4 mounting bolts (7) and 2 mounting Disconnect the negative (–) terminal of the bolts (8), and remove pump controller assem- battery beforehand.
50 Disassembly and assembly SEN02716-00 Removal and installation of Installation Carry out the installation in the reverse order of engine controller assembly removal. Removal [*1] Disconnect the negative (–) terminal of the Screw: 3 ± 1 Nm {0.3 ± 0.1 kgm} battery beforehand.
SEN01980-00 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 90 Diagrams and drawings Hydraulic circuit diagram Hydraulic circuit diagram..........................3 PC138US, USLC-8...
SEN01981-01 HYDRAULIC EXCAVATOR 1SHOP MANUAL PC138US-8 PC138USLC-8 Machine model Serial number PC138US-8 20001 and up PC138USLC-8 20001 and up 90 Diagrams and drawings Electrical diagrams and drawings Electrical circuit diagram ..........................3 Connectors table and arrangement drawing....................5 PC138US, USLC-8...
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SEN01981-01 90 Diagrams and drawings PC138US, USLC-8...
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Connectors table and arrangement drawing PC138US, USLC-8 Connectors table and arrangement drawing PC138US, USLC-8 Type of Type of Connector No. Model Component name Address Connector No. Model Component name Address connector connector DT-T Intermediate connector YAZAKI Air conditioner daylight sensor DT-T Intermediate connector DT-T...
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90 Diagrams and drawings SEN01981-01 PC138US, USLC-8...