John Deere 120D Crawler Excavator Operator’s Manual
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OMT237811 – John Deere 120D Crawler Excavator Operator’s Manual
John Deere 120D Crawler Excavator Operator’s Manual (OMT237811) Overview
The John Deere 120D Crawler Excavator Operator’s Manual (OMT237811) is an essential guide designed to provide operators with detailed instructions for safe operation, routine maintenance, and system overviews. This manual ensures that the machine performs at its peak efficiency while extending its lifespan.
CONTENTS Introduction
IMPORTANT
EPA Non-road Emissions Control Warranty Statement-Compression Ignition
CARB Non-road Emissions Control Warranty Statement-Compression Ignition
Technical Information Feedback Form
Safety
Safety and Operator Conveniences
General Precautions
Operating Precautions
Maintenance Precautions
Safety Signs
Operation
Operator’s Station
Monitor Operation
Operating the Machine
Maintenance
Machine
Periodic Maintenance
As Required
Every 10 Hours or Daily
Initial Service – 50 Hours
Every 50 Hours or Weekly
Every 100 Hours
Initial Service – 250 Hours
Every 250 Hours
Every 500 Hours
Every 1000 Hours
Every 2000 Hours
Every 4000 Hours
Every 5000 Hours
Every 6000 Hours
Miscellaneous
Machine
Operational Checkout
Troubleshooting
Storage
Machine Numbers
Specifications
Detailed Content and Instructions
The manual covers all aspects of operating and maintaining the John Deere 120D Crawler Excavator. It includes step-by-step instructions, safety guidelines, and troubleshooting tips to assist operators in handling the machine effectively.
Diagrams and Technical Illustrations
To enhance understanding, the manual contains detailed diagrams and schematics that visually represent critical components such as hydraulic circuits, transmission layouts, and electrical connections. These illustrations help operators and technicians quickly identify and resolve issues.
Key Systems Covered in the Manual
Hydraulic System
The hydraulic system section explains the hydraulic pump, control valves, cylinders, and hoses. It includes maintenance schedules, fluid specifications, and troubleshooting steps for issues like pressure loss or slow operations.
Transmission
Operators will find guidance on gear shifting, lubrication, and fluid level checks to keep the excavator’s transmission system operating smoothly. The manual also includes preventive maintenance tips to avoid potential failures.
Electrical Components
The electrical system chapter outlines the battery, alternator, wiring diagrams, and fuse locations. It provides step-by-step instructions on diagnosing and fixing common electrical problems.
Cooling System
To prevent overheating, the manual details radiator maintenance, coolant levels, fan operation, and thermostat checks. Proper cooling system maintenance ensures optimal engine performance.
Axle Maintenance
The axle maintenance section includes lubrication procedures, torque specifications, and component inspections to prevent excessive wear and tear.
By following the John Deere 120D Operator’s Manual (OMT237811), operators can ensure the safe, efficient, and long-lasting use of their equipment.