Komatsu PC138US-8, PC138USLC-8 Hydraulic Excavator Service Manual
1,012 pages · Publication SEN01968-14
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- Models
- PC138US-8, PC138USLC-8
- Serial coverage
- 20001 and up
- Manual type
- Service Manual
- Pages
- 1,012
- Publication
- SEN01968-14
- Condition
- Brand new
What's inside
From the manual's own table of contents: 8 sections, 358 entries. See sample pages (PDF, 717 KB)
Index and foreword49 topics
- Shop Manual, contents binder, binder label and tabs
- Index and foreword
- Foreword and general information
- Specification
- Specification and technical data
- Structure, function and maintenance standard
- Engine and cooling system
- Power train
- Undercarriage and frame
- Hydraulic system, Part 1
- Hydraulic system, Part 2
- Hydraulic system, Part 3
- Work equipment
- Cab and its attachments
- Electrical system
- Standard value table
- Standard service value table
- Testing and adjusting
- Testing and adjusting, Part 1
- Testing and adjusting, Part 2
- Testing and adjusting, Part 3
- Troubleshooting
- Failure code table and fuse locations
- General information on troubleshooting
- Troubleshooting by failure code, Part 1
- Troubleshooting by failure code, Part 2
- Troubleshooting by failure code, Part 3
- Troubleshooting by failure code, Part 4
- Troubleshooting of electrical system (E-mode)
- Troubleshooting of hydraulic and mechanical system (H-mode)
- Troubleshooting of engine (S-mode)
- Disassembly and assembly
- General information on disassembly and assembly
- Hydraulic system
- Work equipment Body
- Diagrams and drawings
- Hydraulic circuit diagram
- Electrical diagrams and drawings
- Composition of shop manual
- Safety notice
- How to read the shop manual
- Explanation of terms for maintenance standard
- Handling of electric equipment and hydraulic component
- Handling of connectors newly used for engines
- How to read electric wire code
- Precautions when carrying out operation
- Method of disassembling and connecting push-pull type coupler
- Standard tightening torque table
- Conversion table
Specification5 topics
- Specification dimension drawing
- Working range diagram
- Specifications
- Weight table
- Table of fuel, coolant and lubricants
Structure, function and maintenance standard33 topics
- Engine mount
- Cooling system
- Swing circle
- Swing machinery
- Track frame
- Idler cushion
- Idler
- Track roller
- Carrier roller
- Sprocket
- Track shoe
- Hydraulic equipment layout drawing
- Valve control
- Hydraulic tank and filter
- Hydraulic pump
- Control valve
- CLSS
- Functions and operation by valve
- PPC valve
- Swing motor
- Travel motor
- Center swivel joint
- Solenoid valve
- PPC accumulator
- Anti-drop valve for boom
- Anti-drop valve for arm
- Dimensions of components
- Hydraulic cylinder
- Air conditioner
- Electronic control system
- Monitor system
- KOMTRAX system
- Sensor
Standard value table2 topics
- Standard value table for engine related parts
- Standard value table for chassis related parts
Testing and adjusting38 topics
- Tools for testing, adjusting, and troubleshooting
- Sketches of special tools
- Testing engine speed
- Testing exhaust temperature
- Checking exhaust gas color
- Adjusting valve clearance
- Testing compression pressure
- Testing blow-by pressure
- Testing engine oil pressure
- Handling fuel system parts
- Releasing residual pressure from fuel system
- Testing fuel pressure
- Testing fuel return rate and fuel leakage
- Bleeding air from fuel circuit
- Checking fuel circuit for leakage
- Testing and adjusting alternator belt tension
- Checking and adjusting air conditioner compressor belt tension
- Testing swing circle bearing clearance
- Checking and adjusting track shoe tension
- Testing and adjusting oil pressure in work equipment, swing, and travel circuits
- Testing control circuit basic pressure
- Testing and adjusting oil pressure in pump PC control circuit
- Testing and adjusting oil pressure in pump LS control circuit
- Testing solenoid valve output pressure
- Testing PPC valve output pressure
- Adjusting play of work equipment and swing PPC valves
- Checking parts which cause hydraulic drift of work equipment
- Testing and adjusting travel deviation
- Releasing residual pressure from hydraulic circuit
- Testing oil leakage
- Bleeding air from each part
- Checking cab tipping stopper
- Adjusting mirrors
- Special functions of machine monitor
- Handling voltage circuit of engine controller
- Preparation work for troubleshooting of electrical system
- Procedure for testing diodes
- Pm Clinic service
Troubleshooting168 topics
- Failure code table
- Fuse locations
- Points to remember when troubleshooting
- Sequence of events in troubleshooting
- Checks before troubleshooting
- Classification and procedures for troubleshooting
- Information in troubleshooting table
- Phenomena looking like troubles and troubleshooting Nos
- Connection table for connector pin numbers
- T- branch box and T- branch adapter table
- Failure code [989L00] Engine controller lock caution 1
- Failure code [989M00] Engine controller lock caution 2
- Failure code [989N00] Engine controller lock caution 3
- Failure code [AB00KE] Charge voltage low
- Failure code [B@BAZG] Eng oil press. low
- Failure code [B@BAZK] Eng oil level low
- Failure code [B@BCNS] Eng coolant overheat
- Failure code [B@HANS] Hydr oil overheat
- Failure code [CA111] ECM critical internal failure
- Failure code [CA115] Eng. Ne and Bkup speed sensor error
- Failure code [CA122] Charge air press sensor high error
- Failure code [CA123] Charge air press sensor low error
- Failure code [CA131] Throttle sensor high error
- Failure code [CA132] Throttle sensor low error
- Failure code [CA144] Coolant temp. sensor high error
- Failure code [CA145] Coolant temp. sensor low error
- Failure code [CA153] Charge air temp. sensor high error
- Failure code [CA154] Charge air temp. sensor low error
- Failure code [CA187] Sensor sup. 2 volt. low error
- Failure code [CA221] Ambient air press. sensor high error
- Failure code [CA222] Ambient air press. sensor low error
- Failure code [CA227] Sensor sup. 2 volt. high error
- Failure code [CA234] Eng. overspeed
- Failure code [CA238] Ne speed sensor sup. volt. error
- Failure code [CA271] IMV/PCV1 short error
- Failure code [CA272] IMV/PCV1 open error
- Failure code [CA322] Injector #1 (L #1) system open/short error
- Failure code [CA324] Injector #3 (L/B #3) system open/short error
- Failure code [CA331] Injector #2 (L/B #2) system open/short error
- Failure code [CA332] Injector #4 (L/B #4) system open/short error
- Failure code [CA351] Inj. drive circuit error
- 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
- Failure code [CA441] Battery voltage low error
- Failure code [CA442] Battery voltage high error
- Failure code [CA449] Rail press. very high error
- Failure code [CA451] Rail press. sensor high error
- Failure code [CA452] Rail press. sensor low error
- Failure code [CA553] Rail press. high error
- Failure code [CA559] Rail press. low error
- Failure code [CA689] Eng. Ne speed sensor error
- Failure code [CA731] Eng. Bkup speed sensor phase error
- Failure code [CA757] All persistent data lost error
- Failure code [CA778] Eng. Bkup speed sensor error
- Failure code [CA1633] KOMNET datalink timeout error
- Failure code [CA2185] Throttle sens. sup. volt. high error
- Failure code [CA2186] Throttle sens. sup. volt. low error
- Failure code [CA2249] Rail press. very low error
- Failure code [CA2311] Abnormality in IMV solenoid
- Failure code [D110KB] Battery relay drive short
- Failure code [D19JKZ] Personal code relay abnormality
- Failure code [D862KA] GPS antenna discon
- Failure code [DA22KK] Pump solenoid power low error
- Failure code [DA25KP] 5V sensor 1 power abnormality
- Failure code [DA26KP] 5V sensor 2 power abnormality
- Failure code [DA2RMC] CAN discon (Pump controller detected)
- Failure code [DAF8KB] Short circuit in camera power supply
- Failure code [DAFGMC] GPS module error
- Failure code [DAFRMC] CAN discon (Monitor detected)
- Failure code [DGH2KB] Hydr oil sensor short
- Failure code [DHPAMA] Pump press sensor abnormality
- Failure code [DHSFMA] Travel left forward PPC press sensor abnormality
- Failure code [DHSGMA] Travel right forward PPC press sensor abnormality
- Failure code [DHSHMA] Travel left reverse PPC press sensor abnormality
- Failure code [DHSJMA] Travel right reverse PPC press sensor abnormality
- Failure code [DHSKMA] Blade raise PPC press sensor abnormality
- Failure code [DHSLMA] Blade lower PPC press sensor abnormality
- Failure code [DHX1MA] Overload sensor abnormality (Analog)
- Failure code [DV20KB] Travel alarm S/C
- Failure code [DW43KA] Travel speed sol discon
- Failure code [DW43KB] Travel speed sol short
- Failure code [DW45KA] Swing brake sol discon
- Failure code [DW45KB] Swing brake sol short
- Failure code [DW91KA] Travel junction sol discon
- Failure code [DW91KB] Travel junction sol short
- Failure code [DWJ0KA] Merge-divider sol discon
- Failure code [DWJ0KB] Merge-divider sol short
- Failure code [DXA8KA] PC-EPC sol discon
- Failure code [DXA8KB] PC-EPC sol short
- Failure code [DXE4KA] Service current EPC discon
- Failure code [DXE4KB] Service current EPC short
- Failure code [DY20KA] Wiper working abnormality
- Failure code [DY20MA] Wiper parking abnormality
- Failure code [DY2CKA] Washer drive discon
- Failure code [DY2CKB] Washer drive short
- Failure code [DY2DKB] Wiper drive (for) short
- Failure code [DY2EKB] Wiper drive (rev) short
- Before carrying out troubleshooting of electrical system
- E-1 When starting switch turned ON, machine monitor displays nothing
- E-2 When starting switch turned ON (before starting engine), basic check item lights up
- E-3 Engine does not start (Engine does not turn)
- E-4 Preheater does not operate
- E-5 Automatic warm-up system does not operate (in cold season)
- E-6 All work equipment, swing, and travel mechanism do not move or cannot be locked
- E-7 Precaution lights up while engine is running
- E-8 Emergency stop item lights up while engine is running
- E-9 Engine coolant temperature gauge does not indicate normally
- E-10 Hydraulic oil temperature gauge does not indicate normally
- E-11 Fuel level gauge does not indicate normally
- E-12 Contents of display by machine monitor are different from applicable machine
- E-13 Machine monitor does not display some items
- E-14 Function switch does not work
- E-15 Auto-decelerator does not operate normally
- E-16 Working mode does not change
- E-17 Travel speed does not change
- E-18 Alarm buzzer cannot be stopped
- E-19 Windshield wiper and window washer do not operate
- E-20 Swing holding brake does not operate normally
- E-21 Travel alarm does not sound or does not stop sounding
- E-23 While starting switch is in OFF position, service meter is not displayed
- E-24 Machine monitor cannot be set in service mode
- E-25 Monitoring function does not display lever control signal normally
- E-26 KOMTRAX system does not operate normally
- Information contained in troubleshooting table
- System chart for hydraulic and mechanical systems
- H-1 Speed or power of all work equipment, swing, and travel are low
- H-2 Engine speed sharply drops or engine stalls
- H-3 No work equipment, travel and swing move
- H-4 Abnormal noise is heard from around hydraulic pump
- H-5 Fine control mode does not function
- H-6 Speed or power of boom is low
- H-7 Speed or power of arm is low
- H-8 Speed or power of bucket is low
- H-9 Work equipment does not move in its single operation
- H-10 Hydraulic drift of work equipment is large
- H-11 Time lag of work equipment is large
- H-12 Work equipment loaded more is slower during compound operation
- H-13 Boom RAISE speed is low in compound operation of swing + boom RAISE
- H-15 Machine deviates during travel
- H-16 Travel speed is low
- H-17 Machine cannot be steered easily or steering power is low
- H-18 Travel speed does not change or it is kept low or high
- H-19 Track does not move (Only either side)
- H-20 Machine does not swing
- H-21 Swing acceleration or swing speed is low
- H-22 Excessive overrun when stopping swing
- H-23 When upper structure stops swinging, it makes large shock
- H-24 When upper structure stops swinging, it makes large sound
- H-25 Hydraulic drift of swing is large
- H-26 Flow rate in attachment circuit cannot be adjusted
- Method of using troubleshooting chart
- S-1 Starting performance is poor
- S-2 Engine does not start
- S-3 Engine does not pick up smoothly
- S-4 Engine stops during operations
- S-5 Engine does not rotate smoothly
- S-6 Engine lacks output (or lacks power)
- S-7 Exhaust smoke is black (incomplete combustion)
- S-8 Oil consumption is excessive (or exhaust smoke is blue)
- S-9 Oil becomes contaminated quickly
- S-10 Fuel consumption is excessive
- S-11 Oil is in coolant (or coolant spurts back or coolant level goes down)
- S-12 Oil pressure drops
- S-13 Oil level rises (Entry of coolant or fuel)
- S-14 Coolant temperature becomes too high (overheating)
- S-15 Abnormal noise is made
- S-16 Vibration is excessive
Disassembly and assembly53 topics
- How to read this manual
- Coating materials list
- Special tool list
- Sketch of special tool
- Removal and installation of fuel supply pump assembly
- Removal and installation of fuel injector assembly
- Removal and installation of front oil seal
- Removal and installation of rear oil seal
- Removal and installation of cylinder head assembly
- Removal and installation of radiator assembly
- Removal and installation of aftercooler assembly
- Removal and installation of work equipment oil cooler assembly
- Removal and installation of engine and work equipment pump assembly
- Removal and installation of fuel tank assembly
- Removal and installation of travel motor and final drive assembly
- Disassembly and assembly of travel motor and final drive assembly
- Removal and installation of swing motor and swing machinery assembly
- Disassembly and assembly of swing machinery assembly
- Removal and installation of swing circle assembly
- Disassembly and assembly of track roller
- Disassembly and assembly of idler assembly
- Disassembly and assembly of recoil spring
- Removal and installation of of track shoe assembly
- Removal and installation of sprocket
- Removal and installation of revolving frame assembly
- Removal and installation of counterweight assembly (Machine without add-on weight)
- Removal and installation of counterweight assembly (Machine with add-on weight)
- Removal and installation of center swivel joint assembly
- Disassembly and assembly of center swivel joint assembly
- Removal and installation of hydraulic tank assembly
- Removal and installation of hydraulic pump assembly
- Removal and installation of main pump input shaft oil seal
- Removal and installation of control valve assembly
- Disassembly and assembly of control valve assembly
- Disassembly and assembly of work equipment PPC valve assembly
- Disassembly and assembly of travel PPC valve assembly
- Removal and installation of anti-drop valve for boom assembly
- Removal and installation of anti-drop valve for arm assembly
- Disassembly and assembly of anti-drop valve assembly
- Disassembly and assembly of hydraulic cylinder assembly
- Removal and installation of work equipment assembly
- Removal and installation of operator cab assembly
- Removal and Installation of operator's cab door
- Removal and installation of operator's cab glass (stuck glass)
- Removal and installation of front window assembly
- Removal and installation of floor frame assembly
- Removal and installation of air compressor assembly
- Removal and installation of air conditioner condenser
- Removal and installation of air compressor unit assembly
- Removal and installation of machine monitor assembly
- Removal and installation of pump controller assembly
- Removal and installation of engine controller assembly
- Removal and installation of KOMTRAX communications module
Diagrams and drawings2 topics
- Electrical circuit diagram
- Connectors table and arrangement drawing
Inside this manual
Real pages from this service manual (1,012 pages). Open the sample pages (PDF, 717 KB)
- Specifications, page 328: 20 Standard value table
- Troubleshooting, page 583: Failure code [CA731] Eng. Bkup speed sensor phase error
- Diagram, page 703: E-21 Travel alarm does not sound or does not stop sounding
- Foldout diagram: Electrical circuit diagram (1/6)
Other manuals for this machine
Save 10% on 2 manuals, 15% on 3 or more. Other manuals for the PC138US-8, PC138USLC-8 are listed below. Editions cover different serial number ranges: check the serial coverage and tick only the ones that match your machine.
This manual: Service Manual SEN01968-14$109.71
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This is a service manual
Here's how it compares to the other manual types.
This manual
Service manual
Factory repair procedures and technical information such as specifications, troubleshooting, and wiring and hydraulic diagrams, for the models and systems the manual covers. See What's inside for its topics.
Operator's manual
Safe operation, controls, maintenance schedules, lubrication points, inspections, and basic checks. Repair procedures are in the service manual.
Parts manual
Illustrated diagrams with factory part numbers for identifying components and ordering parts. Repair procedures are in the service manual.
Engine service manuals are sometimes sold separately, since certain machine models were offered with more than one engine option.
What it's used for
Factory manual for in-house farm and construction shop use. Straightforward, complete, and easy to follow. It contains the OEM information dealership service departments and parts counters use to diagnose problems, identify components, and perform maintenance or repairs correctly.
Service shops and owner/operators who repair their own equipment
Identifying correct parts and seeing how assemblies come apart and go back together
Keeping equipment running with less downtime
Factory manual, 1,012 pages
Quantity one is the manual described above.
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Binder not included
Manuals over about 300 pages may need a standard 3-ring binder, which you can buy locally to keep the pages organized for shop use.
Questions about model, serial number, engine coverage or contents? Contact us before purchasing and we'll help confirm it's the right manual. Please verify the manual type, machine model, serial number range and engine coverage before purchasing: manuals ordered in error carry a 20% restocking fee (return policy).