Komatsu Mini Excavator PC78US-11 service & repair manual

Description Komatsu Mini Excavator PC78US-11 service & repair manual

Komatsu Mini Excavator PC78US-11 pdf workshop service & repair manual

Serial number 50001 and up

Technical data, specifications, testing, troubleshooting, maintenance, electrical diagrams, hydraulic schematics, adjusting, assembly, disassembly, removal, installation instructions and other information

SERVICE MANUAL CONTENT:
Index and Foreword
Foreword, Safety, Basic Information
How to Read the Shop Manual
Safety Notice for Operation
Precautions to Prevent Fire
Procedures If Fire Occurs
Precautions When You Discard Waste Materials
Precautions When You Handle Hydraulic Equipment
Precautions When You Disconnect and Connect Pipings
Precautions When You Handle Electrical Equipment
Precautions When You Handle Fuel System Equipment
Precautions When You Handle Intake System Equipment
Practical Use of KOMTRAX
Disconnect and Connect Push-Pull Type Coupler
Precautions for Disconnection and Connection of Connectors
Disconnect and Connect Deutsch Connector
How to Disconnect and Connect Slide Lock Type Connector
Disconnect and Connect Connector with Lock to Pull
Disconnect and Connect Connector with Lock to Push
Disconnect and Connect Connector with Housing to Rotate
How to Read the Codes for Electric Cable
Explanation of Terms for Maintenance Standard
Standard Tightening Torque Table
Conversion Table
Abbreviation List

Specification
Specification Drawing
Working Range Drawings
Weight Table
Fuel, Coolant, Lubricants

Structure and Function
Boot-up System
Layout Drawing of Boot-up System
System Operating Lamp System
Battery Disconnect Switch
Engine System
Layout Drawing of Engine System
Engine Control System
Auto-Deceleration System
Engine Automatic Warm-up System
Overheat Prevention System
Turbocharger Protection System
Automatic Idle Stop System
Component Parts of Engine System
Cooling System
Layout Drawing of Cooling System
Control System
Layout Drawing of Control System
Machine Monitor System
KOMTRAX System
Component Parts of Control System
Hydraulic System
Layout Drawing of Hydraulic System
CLSS
Engine and Pump Combined Control System
Component Parts of Hydraulic System
Work Equipment System
Layout Drawing of Work Equipment System
PPC Lock System
Work Equipment and Travel Automatic Lock System
Attachment Oil Flow Adjuster System
Component Parts of Work Equipment System
Swing System
Layout Drawing of Swing System
Swing Control System Diagram
Component Parts of Swing System
Travel System
Layout Drawing of Travel System
System Diagram of Travel Control System
Component Parts of Travel System
Undercarriage and Frame
Layout Drawing of Undercarriage
Idler Cushion
Work Equipment
Structure of Work Equipment
Function of Work Equipment
Work Equipment Clearance Adjustment Shim
Bucket Clearance Adjustment Shim
CAB Related Parts
ROPS CAB
CAB Mount
Remove Wiring Harness Out of Cab

Standard Value Table
Standard Value Table for Engine
Standard Value Table for Engine: PC78US-11
Standard Value Table for Machine
Standard Value Table for Machine: PC78US-11
Machine Posture and Procedures to Measure Performance

Testing and Adjusting
Table of Contents
Precautions Before Work
Related Information on Testing and Adjusting
Tools for Testing and Adjusting
Sketch of Tools for Testing and Adjusting
Engine and Cooling System
Examine Engine Speed
Examine Exhaust Gas Color
Examine and Adjust Valve Clearance
Examine Compression Pressure
Examine Blowby Pressure
Examine Engine Oil Pressure
Visual Check Inside of EGR Valve
Clean Inside of EGR Valve
Examine Fuel Pressure
Examine Fuel Return Rate and Leakage
Bleed Air from Fuel System
Examine Fuel Circuit for Leakage
Handle Cylinder Cut-out Mode Operation
Handle No-Injection Cranking Operation
Examine Fan Belt
Examine Automatic Tensioner
Write Injector Compensation Value to Engine Controller
Power Train
Examine Swing Circle Bearing Clearance
Undercarriage and Frame
Examine and Adjust Track Tension
Hydraulic System
Release Remained Pressure in Hydraulic Circuit
Examine and Adjust Oil Pressure in Work Equipment and Travel Circuits
Examine and Adjust Swing and Blade Circuit Oil Pressure
Examine Oil Pressure of Control Circuit
Examine and adjust oil pressure in pump PC control circuit
Examine and Adjust Oil Pressure in Pump LS Control Circuit
Examine Outlet Pressure of Solenoid Valve
Examine PPC Valve Outlet Pressure
Examine and Adjust Travel Deviation
Examine Parts Which Cause Hydraulic Drift of Work Equipment
Examine Oil Leakage
Bleed Air from Hydraulic System
CAB Related Parts
How to Adjust Mirrors
How to Examine and Adjust Slide Door
Electrical System
Set and Operate Machine Monitor
Start Up KOMTRAX System
Adjust Rearview Camera Angle
Adjust Rightview Camera Angle
Set Region of Bluetooth® Compatible Radio
Handle Voltage Circuit of Engine Controller
Handle Battery Disconnect Switch
Examine Diodes
Pm Clinic
Pm Clinic Service

Troubleshooting
Precautions Before Work
Related Information to Troubleshooting
General Troubleshooting Points
Sequence of Events in Troubleshooting
Checks Before Troubleshooting
Inspection Procedure Before Troubleshooting
Test in Accordance with Testing Procedure
Preparation for Troubleshooting of Electrical System
Procedure for Troubleshooting
Symptom and Troubleshooting Numbers
Information Shown in Troubleshooting Table
Diagnose Open Circuit of Hydraulic Pressure Sensor System Wiring Harness
Connectors List
Connector Layout
Connector Contact Connection Table
T-Branch Box and T-Branch Adapter Table
Fuse Location Table
Failure Code Table
Troubleshooting by Failure Code (Display of Code)
Troubleshooting of Electrical System (E-Mode)
Troubleshooting for Hydraulic and Mechanical Systems (H Mode)
Troubleshooting of Engine (S-Mode)

Disassembly and Assembly
Precautions Before Work
Related Information on Disassembly and Assembly
How to Read This Manual
Coating Materials List
Special Tool List
Sketches of Special Tools
Prepare
Drain and Add Coolant
Drain and Add Hydraulic Oil
Drain and Add Fuel
Collect and Refill Refrigerant
Engine and Cooling System
Remove and Install Supply Pump Assembly
Remove and Install Injector Assembly
Remove and Install Cylinder Head Assembly
Remove and Install EGR Valve Assembly
Remove and Install EGR Cooler Assembly
Remove and Install Starter Assembly
Remove and Install Fan Belt
Remove and Install Automatic Tensioner
Remove and Install Expansion Tank Assembly
Remove and Install Radiator Assembly
Remove and Install Hydraulic Oil Cooler Assembly
Remove and Install Aftercooler Assembly
Remove and Install Engine and Main Pump Assembly
Remove and Install Engine Front Oil Seal
Remove and Install Engine Rear Oil Seal
Remove and Install Fuel Cooler Assembly
Remove and Install Engine Hood Assembly
Remove and Install KDOC Assembly
Remove and Install Fuel Tank Assembly
Remove and Install Air Cleaner Assembly
Remove and Install Air Conditioner Compressor Assembly
Remove and Install Air Conditioner Condenser Assembly
Power Train
Remove and Install Travel Motor and Final Drive Assembly
Disassemble and Assemble Travel Motor and Final Drive Assembl
Remove and Install Swing Motor and Swing Machinery Assembly
Disassemble and Assemble Swing Machinery Assembly
Remove and Install Swing Circle Assembly
Undercarriage and Frame
Separate and Connect Track Assembly
Remove and Install Sprocket
Remove and Install Idler and Idler Cushion Assembly
Disassemble and Assemble Idler Assembly
Disassemble and Assemble Idler Cushion Assembly
Disassemble and Assemble Track Roller Assembly
Remove and Install Revolving Frame Assembly
Remove and Install Counterweight Assembly
Hydraulic System
Remove and Install Center Swivel Joint Assembly
Disassemble and Assemble Center Swivel Joint Assembly
Remove and Install Hydraulic Tank Assembly
Remove and Install Main Pump Assembly
Remove and Install Control Valve Assembly
Disassemble and Assemble Control Valve Assembly
Disassemble and Assemble Work Equipment PPC Valve Assembly
Disassemble and Assemble Travel PPC Valve Assembly
Work Equipment
Remove and Install Blade Assembly
Remove and Install Work Equipment Assembly
Remove and Install Boom Anti-drop Valve Assembly
Remove and Install Arm Anti-Drop Valve Assembly
Disassemble and Assemble Anti-Drop Valve Assembly
Disassemble and Assemble Boom Cylinder Assembly
Disassemble and Assemble Arm Cylinder Assembly
Disassemble and Assemble Bucket Cylinder Assembly
Disassemble and Assemble Blade Cylinder Assembly
CAB Related Parts
Remove and Install Operator Cab Assembly
Remove and Install Slide Door
Remove and Install Operator Cab Glass (Adhered Glass)
Remove and Install Front Window Assembly
Remove and Install Floor Frame Assembly
Remove and Install Air Conditioner Unit Assembly
Remove and Install Operator Seat
How to Remove and Install Seat Belt
Remove and Install Work Equipment Control Lever Assembly
Remove and Install Front Wiper Assembly
Electrical System
Remove and Install Engine Controller Assembly
Remove and Install Pump Controller Assembly
Remove and Install Machine Monitor Assembly
Remove and Install Mass Air Flow and Temperature Sensor
Remove and Install Gateway Function Controller

Maintenance Standard
Engine and Cooling System
Maintenance Standard for Engine Mount
Maintenance Standard for PTO
Maintenance Standard for Cooling System
Power Train
Maintenance Standard for Swing Circle
Maintenance Standard for Swing Machinery
Maintenance Standard for Sprocket
Undercarriage and Frame
Maintenance Standard for Track Frame and Idler Cushion
Maintenance Standard for Idler
Maintenance Standard for Track Roller
Maintenance Standard for Carrier Roller
Maintenance Standard for Track Shoes
Maintenance Standard for Triple Shoes
Maintenance Standard for Rubber Shoes
Hydraulic System
Maintenance Standard for Hydraulic Tank
Maintenance Standard for Main Pump
Maintenance Standard for PC-EPC Valve
Maintenance Standard for Swing Motor
Maintenance Standard for Travel Motor
Maintenance Standard for Control Valve
Maintenance Standard for Boom Anti-Drop Valve
Maintenance Standard for Arm Anti-Drop Valve
Maintenance Standard for Work Equipment and Swing PPC Valve
Maintenance Standard for Blade PPC Valve
Maintenance Standard for Travel PPC Valve
Maintenance Standard for 1st-Line Attachment PPC Valve (with EPC Valve)
Maintenance Standard for Solenoid Valve
Maintenance Standard for Attachment Oil Flow Adjuster EPC Valve
Maintenance Standard for Attachment Circuit Accumulator (For Low Pressure Circuit)
Maintenance Standard for Center Swivel Joint
Work Equipment
Maintenance Standard for Work Equipment Linkage
Maintenance Standard for Boom Cylinder
Maintenance Standard for Arm Cylinder
Maintenance Standard for Bucket Cylinder
Maintenance Standard for Blade Cylinder

Appendix
Precautions Before Work
Air Conditioner System
Precautions for Refrigerant
Air Conditioner Component
Specifications of Air Conditioner
Structure and Function of Refrigeration Cycle
Outline of Refrigeration Cycle
Component Parts of Air Conditioner System
Air Conditioner Unit
Component Parts of Air Conditioner Unit
Air Conditioner Controller
Compressor
Condenser
Receiver Drier
Air Conditioner Related Sensors
Explanation of Procedure for Test of and Troubleshooting of Air Conditioner
Circuit Diagram and Configuration of Connector Pins of Air Conditioner
System Diagram of Air Conditioner
Input and Output Signals of Air Conditioner Controller
Locations of Air Conditioner Parts and Layout of Connectors
Examine Air Leakage (Duct)
How to Examine Air Leakage (Duct)
Examine Air Conditioner with Self-Diagnosis Function
Open the Electrical System Abnormality Record Screen in Service Mode of Machine Monitor
Examine Vent (Mode) Changeover
How to Examine Vent (Mode) Changeover
Examine Fresh/Recirc Air Changeover
How to Examine Fresh/Recirc Air Changeover
Examine Sunlight Sensor
How to Examine Sunlight Sensor
Examine Refrigerant (Dual) Pressure Switch
How to Examine Refrigerant (Dual) Pressure Switch
Examine Relay
How to Examine Relay
Air Conditioner Troubleshooting Chart
Information Shown in Troubleshooting Table
A-1 Troubleshooting for Power Supply System (Air Conditioner Does Not Operate)
A-2 Troubleshooting for Compressor and Refrigerant System (Air is Not Cooled)
A-3 Troubleshooting for Blower Motor System (No Air Comes Out or Air Flow is Abnormal)
A-4 Troubleshooting for Fresh/Recirc Air Changeover
Troubleshooting by Gauge Pressure
Connect Service Tool
How to Connect Service Tool
Precautions for Disconnection and Connection of Air Conditioner Piping
Handle Compressor Oil

Circuit Diagrams
How to Read the Codes for Electric Cable
Hydraulic Circuit Diagram
Symbols Used in Hydraulic Circuit Diagram
Hydraulic Circuit Diagram (at Boom Raise Operation)
Hydraulic Circuit Diagram (at Left Swing Operation)
Hydraulic Circuit Diagram (at Boom Raise and Left Swing Operation)
Electrical Circuit Diagram
Symbols Used in Electric Circuit Diagram
Electrical Circuit Diagram (Machine with Proportional Control Lever)

Engine SAA3D95E-1 workshop service repair manual