John Deere 120d Excavator Service Repair Manual
TM10737
John Deere 120d Excavator Diagnostic, Operation Test Service Manual
John Deere 120D Excavator Service Repair Manual Overview
The John Deere 120D Excavator Service Repair Manual is an essential guide for technicians, mechanics, and machine owners who need detailed maintenance and repair information. This manual provides step-by-step instructions, diagrams, and technical specifications to ensure proper servicing of the John Deere 120D excavator.
Detailed Content and Instructions
The manual is divided into well-organized sections covering all major components of the excavator. Each section includes detailed troubleshooting guides, repair procedures, and safety precautions to help users efficiently diagnose and fix issues.
Diagrams and Illustrations
Comprehensive wiring diagrams, hydraulic schematics, and exploded component views are included to assist with repairs. These illustrations make it easier to identify parts and understand complex systems within the machine.
Hydraulic System
The hydraulic system section provides in-depth details on hydraulic pumps, control valves, cylinders, and hoses. It covers maintenance procedures such as fluid replacement, leak detection, and pressure adjustments to ensure optimal performance.
John Deere 120d Excavator Service Repair Manual
Repair Technical Manual Contains:
John Deere 120D Excavator Service Repair Manual – Section List
SECTION 00 – General Information
- Group 0001 – Safety
- Group 0003 – Torque Values
SECTION 01 – Tracks
- Group 0130 – Track System
SECTION 02 – Axles and Suspension Systems
- Group 0250 – Axle Shaft, Bearings, and Reduction Gears
- Group 0260 – Hydraulic System
SECTION 04 – Engine
- Group 0400 – Removal and Installation
SECTION 05 – Engine Auxiliary Systems
- Group 0510 – Cooling System
- Group 0520 – Intake System
- Group 0560 – External Fuel Supply Systems
SECTION 07 – Dampener Drive (Flex Coupling)
- Group 0752 – Elements
SECTION 17 – Frame or Supporting Structure
- Group 1740 – Frame Installation
- Group 1749 – Chassis Weights
SECTION 18 – Operator’s Station
- Group 1800 – Removal and Installation
- Group 1810 – Operator Enclosure
- Group 1821 – Seat and Seat Belt
- Group 1830 – Heating and Air Conditioning
SECTION 32 – Bulldozers (Backfill Blade)
- Group 3201 – Blades
- Group 3260 – Hydraulic System
SECTION 33 – Excavator
- Group 3302 – Buckets
- Group 3340 – Frames
- Group 3360 – Hydraulic System
SECTION 43 – Swing or Pivoting System
- Group 4350 – Mechanical Drive Elements
- Group 4360 – Hydraulic System
SECTION 99 – Dealer Fabricated Tools
Group 9900 – Dealer Fabricated Tools
Transmission and Axle Maintenance
The transmission system section outlines gear shifting mechanisms, clutch adjustments, and lubrication requirements. The axle maintenance guide explains how to inspect and service the drive shafts, bearings, and differential components to prevent mechanical failure.
Electrical Components
The manual contains detailed wiring diagrams for the starter, alternator, lighting system, and control panel. Troubleshooting steps help diagnose battery issues, sensor malfunctions, and electrical faults.
Cooling System
A dedicated section covers the radiator, coolant lines, water pump, and thermostat. Proper maintenance procedures, such as coolant flushing and fan belt inspection, are provided to prevent overheating.
By using the John Deere 120D Excavator Service Repair Manual, technicians can ensure efficient operation, prolong equipment lifespan, and minimize downtime.