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SEN06518-03 HYDRAULIC PC78US EXCAVATOR 30001 SERIAL NUMBERS and up...
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00 INDEX AND FOREWORD PC78US-10 00-1 Find manuals at https://best-manuals.com...
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AUTOMATIC IDLE STOP SYSTEM ....................10-26 COMPONENT PARTS OF ENGINE SYSTEM ................10-29 COOLING SYSTEM..........................10-44 LAYOUT DRAWING OF COOLING SYSTEM ................10-44 CONTROL SYSTEM..........................10-47 LAYOUT DRAWING OF CONTROL SYSTEM ................10-47 MACHINE MONITOR SYSTEM ..................... 10-49 00-2 PC78US-10 Find manuals at https://best-manuals.com...
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CONTENTS ............................20-2 ABBREVIATION LIST ..........................20-3 STANDARD VALUE TABLE FOR ENGINE ..................... 20-9 STANDARD VALUE TABLE FOR ENGINE: PC78US-10 ..............20-9 STANDARD VALUE TABLE FOR MACHINE..................20-12 STANDARD VALUE TABLE FOR MACHINE: PC78US-10............. 20-12 MACHINE POSTURE AND PROCEDURE FOR MEASURING PERFORMANCE ......20-26 STANDARD VALUE TABLE FOR ELECTRICAL ...................
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INFORMATION DESCRIBED IN TROUBLESHOOTING TABLE............ 40-59 TROUBLESHOOTING METHOD FOR OPEN CIRCUIT IN WIRING HARNESS OF PRESSURE SEN- SOR SYSTEM..........................40-61 CONNECTORS LIST AND LAYOUT....................40-63 CONNECTOR CONTACT IDENTIFICATION ................. 40-74 T-BRANCH BOX AND T-BRANCH ADAPTER TABLE ..............40-114 00-4 PC78US-10 Find manuals at https://best-manuals.com...
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E-6 HYDRAULIC OIL TEMPERATURE MONITOR LIGHTS UP IN WHITE WHILE ENGINE IS RUN- NING ............................40-433 E-7 CHARGE LEVEL MONITOR LIGHTS UP IN RED WHILE ENGINE IS RUNNING ....40-434 E-8 FUEL LEVEL MONITOR LIGHTS UP IN RED WHILE ENGINE IS RUNNING......40-435 PC78US-10 00-7 Find manuals at https://best-manuals.com...
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E-43 BOOM LOWER INDICATOR IS NOT DISPLAYED PROPERLY WITH MONITORING FUNCTION ..............................40-482 E-44 ARM OUT INDICATOR IS NOT DISPLAYED PROPERLY WITH MONITORING FUNCTION................................40-483 E-45 ARM IN INDICATOR IS NOT DISPLAYED PROPERLY WITH MONITORING FUNCTION ..40-484 00-8 PC78US-10 Find manuals at https://best-manuals.com...
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DIRECTION EITHER RIGHT OR LEFT)..................40-557 H-32 SHOCK IS LARGE WHEN UPPER STRUCTURE STOPS SWINGING .......40-558 H-33 LARGE UNUSUAL NOISE IS HEARD WHEN UPPER STRUCTURE STOPS SWINGING..40-559 H-34 SWING DRIFT ON A SLOPE IS LARGE (WHILE SWING PARKING BRAKE IS APPLIED).40-560 PC78US-10 00-9...
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REMOVE AND INSTALL KDOC MUFFLER ..................50-149 REMOVE AND INSTALL FUEL TANK ASSEMBLY ...............50-157 REMOVE AND INSTALL KCCV VENTILATOR ASSEMBLY ............50-163 REMOVE AND INSTALL AIR CLEANER ASSEMBLY..............50-167 REMOVE AND INSTALL AIR CONDITIONER COMPRESSOR ASSEMBLY ........50-170 REMOVE AND INSTALL AIR CONDITIONER CONDENSER ASSEMBLY ........50-175 00-10 PC78US-10...
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MAINTENANCE STANDARD OF ENGINE MOUNT ................ 60-9 MAINTENANCE STANDARD FOR PTO ..................60-10 MAINTENANCE STANDARD OF COOLING SYSTEM ..............60-11 POWER TRAIN............................. 60-13 MAINTENANCE STANDARD OF SWING CIRCLE ................ 60-13 MAINTENANCE STANDARD OF SWING MACHINERY..............60-15 MAINTENANCE STANDARD OF SPROCKET ................60-17 PC78US-10 00-11...
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AIR CONDITIONER SYSTEM DIAGRAM ..................... 80-35 INPUT AND OUTPUT SIGNALS OF AIR CONDITIONER CONTROLLER ........80-36 INSTALLATION LOCATIONS OF AIR CONDITIONER PARTS AND ARRANGEMENT OF CONNECTORS ................................80-38 TESTING AIR LEAKAGE (DUCT)......................80-44 METHOD FOR TESTING AIR LEAKAGE (DUCT) ................. 80-44 00-12 PC78US-10...
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INDEX 00 INDEX AND FOREWORD ELECTRICAL CIRCUIT DIAGRAM (FOR EUROPEAN UNION) (4/6) ..........90-41 ELECTRICAL CIRCUIT DIAGRAM (FOR EUROPEAN UNION) (5/6) ..........90-43 ELECTRICAL CIRCUIT DIAGRAM (FOR EUROPEAN UNION) (6/6) ..........90-45 INDEX..................................1 00-14 PC78US-10...
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(provides better Sensing System combined operation than OLSS). Engine controller electronically controls supply pump, common rail, and injector. This function Common Rail Injection Engine maintains optimum fuel injection amount and fuel injection timing. PC78US-10 00-15...
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Technology tronic control and communication. This valve is installed at inlet port of pump, and it adjusts fuel intake amount in order to control fuel Inlet Metering Actuator Engine discharged volume of supply pump. (Same as IMV) 00-16 PC78US-10...
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Inlet Metering Valve Engine discharged volume of supply pump. (Same as IMA) This mechanism separates oil in blowby gas and Komatsu Closed Crank- KCCV Engine returns it to the intake side to combust it there. It case Ventilation primarily consists of filters.
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Tip-Over Protectuive chine when it is overtuned.(Hydraulic excavator TOPS Cab and canopy Structure tip-over protective structure) Structure which is standardized as ISO 12117. Solenoid valve that switches over direction of 2-Way Valve Hydraulic system flow. 00-18 PC78US-10...
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Auxiliary Battery Relay Clockwise Counter Clockwise Electronic Control Unit Electronic Control Module Engine EXGND External Ground F.G. Frame Ground Ground Inlet Metering Actuator No Connection Steering STRG Signal Solenoid Standard Option PRESS Pressure SPEC Specification Switch TEMP Temperature PC78US-10 00-19...
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ABBREVIATION LIST 00 INDEX AND FOREWORD Abbreviation Actual word spelled out Torque Converter Transmission 00-20 PC78US-10...
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REMARK • Some of the attachments and options described in this shop manual may not be available in some areas. If they are required, consult your Komatsu distributor. • The materials and specifications are subject to change without notice. • Shop Manuals are available for "machine part" and "engine part". For the engine unit, see the shop manual for the machine which has the same engine model.
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REMARK Remark This signal word contains useful information to know. Unit International System of Units (SI) is used in this manual. For reference, units that have been used in the past are given in { }. 00-22 PC78US-10...
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Appropriate servicing and repair are extremely important to ensure safe operation of the machine. The shop manuals describe the effective and safe servicing and repair methods recommended by Komatsu. Some of the servicing and repair methods require the use of special tools designed by Komatsu for special purpos- •...
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Then, disconnect the quick release battery terminal (-). REMARK For the machine without the system operating lamp, turn the starting switch to OFF position, wait for two minutes or more before starting the work. Disconnect the quick release battery terminal (-). 00-24 PC78US-10...
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• Do not use gasoline to wash parts as a general rule. Do not use gasoline to clean electrical parts, in partic- ular. PC78US-10 00-25...
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• Hanging angle must be 60 ° or smaller as a rule. • When slinging a heavy load (25 kg or heavier), the hanging angle of the rope must be narrower than that of the hook. 00-26 PC78US-10...
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Precautions for using mobile crane REMARK Read Operation and Maintenance Manual of the crane carefully in advance and operate the crane safely. Precautions for using overhead traveling crane When raising a heavy component (heavier than 25 kg), use a hoist or crane. PC78US-10 00-27...
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When tightening nuts of the air conditioner hoses and tubes, be sure to use 2 wrenches. Use one wrench to fix and tighten the nut with the other wrench to the specified torque (Use a torque wrench for tightening). PC78US-10 00-29...
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• The figure shows an example of fitting of O-ring. • An O-ring is fitted to every joint of the air conditioner piping. For tightening torques, see THE OTHER INFORMATION, "Pre- cautions for disconnection and connection of air conditioner piping". 00-30 PC78US-10...
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Fire around the machine due to highly heated exhaust gas Some models and specifications may be equipped with KDPF (Komatsu Diesel Particulate Filter). KDPF is a system for purifying exhaust gas by removing soot in exhaust gas. In the process of purification (re- generation), the temperature of discharged exhaust gas may be higher than that of conventional models.
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• When checking fuel, oil, battery electrolyte, or coolant, always use lighting equipment with anti-explosion specifications. • When taking the electrical power for the lighting equipment from the machine, follow the instructions in the Operation and Maintenance Manual. 00-32 PC78US-10...
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Be sure to wear rubber gloves when handling the materials left after the fire. The material of the gloves, which is recommended is polychloroprene (Neoprene) or polyvinyl chloride (in the lower temperature environment). When wearing cotton work gloves, wear rubber gloves under them. PC78US-10 00-33...
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Avoid exposure to burning rubber or plastics which produce a toxic gas that is harmful to people. • When disposing of parts made of rubber or plastics (hoses, cables, and harnesses), always comply with the local regulations for disposing industrial waste products. 00-34 PC78US-10...
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Do not discard the oil inconsiderately. Ask the customer for disposal or bring it back to dispose it ap- propriately. REMARK Cover the places tightly with caps, tapes, or plastic bags if it is hard to provide the plugs. PC78US-10 00-35...
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Cleaning operation Perform oil cleaning to remove the contaminants and sludges in the hydraulic circuit after repair of the hydraulic device (pump, or control valve) or during operation of the machine. 00-36 PC78US-10...
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00 INDEX AND FOREWORD PRECAUTIONS FOR HANDLING HYDRAULIC EQUIPMENT REMARK The oil cleaning equipment can remove the ultra fine (approxi- mately 3 μm) particles that the filter built in the hydraulic equip- ment cannot remove. So, it is very effective device. PC78US-10 00-37...
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Introduction of parts for the disassembly of the face seal type hoses and tubes Hose side Pipe joint side Nominal No. O-ring (3) Plug (1) Nut (2) 07376-70210 02789-00210 02896-11008 07376-70315 02789-00315 02896-11009 07376-70422 02789-00422 02896-11012 07376-70522 02789-00522 02896-11015 07376-70628 02789-00628 02896-11018 00-38 PC78US-10...
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Introduction of parts for the removal of O-ring boss type joint Nominal No. Plug (1) O-ring (2) 07040-10807 07002-10823 07040-11007 07002-11023 07040-11209 07002-11223 07040-11409 07002-11423 07040-11612 07002-11623 07040-11812 07002-11823 07040-12012 07002-12034 07040-12412 07002-12434 07041-13012 07002-13034 07040-13316 07002-13334 07041-13612 07002-13634 07040-14220 07002-14234 07040-15223 07002-15234 00-40 PC78US-10...
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When installing split flanges, tighten the bolts uniformly and alternately to prevent uneven tightening. • As a rule, apply liquid gasket (LG-5) or liquid sealant (LS-2) to the threaded portion of each taper male screws which receive pressure. PC78US-10 00-41...
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When the coolant is drained, be sure that the drain valve is securely tightened, then refill the coolant reser- voir with the coolant Komatsu recommends to the specified level. Start the engine to circulate the coolant in the piping, and add the coolant to the specified level again.
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• Parts which connects the above, or etc. Check that there is no unusual noise by comparing to it of the time when the machine was new. If there is any unusual noise, repair KDPF or muffler, referring to "TROUBLESHOOTING" and "DISASSEMBLY AND ASSEMBLY". PC78US-10 00-43...
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The pins of the male and female connectors are attached to wires by crimping or soldering. If excessive force is applied to the wire, the jointed portion (1) may become loose, and it may result in a defective connection or breakage. 00-44 PC78US-10...
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• If there is oil or water in the compressed air, it causes the contacts to become dirtier. Use clean air which any oil and water has been removed from. PC78US-10 00-45...
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If a filter oth- er than a Komatsu genuine filter is used, fuel system contamination and damage may occur. Therefore Komatsu recommends using only Komatsu fuel filters and install them following the procedures in the shop manual.
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Plug the removed pipes and the openings of the removed components with the caps, tapes, plastic bags, etc. to prevent foreign material from entering. NOTICE Do not expose the openings or stuff it, otherwise foreign material may enter it. PC78US-10 00-47...
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To propose the periodic inspection (Pm clinic, etc.) according to the service meter reading. How to operate KOMTRAX For the operating method of each screen of KOMTRAX, ask KOMTRAX key person in your Komatsu distributor. 00-48 PC78US-10...
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