John Deere 644J Loader Repair Service Manual
TM10246

John Deere 644J 724j Operation Tests Technical Manual

Designed to maximize your productivity and uptime while minimizing your daily operating costs, the 225-horsepower Deere 644J combines the muscle of a production machine with the flexibility and maneuverability of a utility loader.

Numerous enhancements within the more spacious cab include a multifunction state-of-the-art monitor, with advanced diagnostics, durable solid-state electrical distribution center, new sealed switch module, and improved ventilation.

Add to that a more efficient drivetrain and hydraulic cooling system with proportional fan control, and you’ve got a multipurpose machine that’ll make any operator and operation more productive.

Productivity never felt this comfortable.

John Deere 644J Repair Service Manual

Essential Maintenance Tips for John Deere 644J Loader Owners

Regular Inspections: Conduct frequent visual inspections of the John Deere 644J loader to identify any signs of wear, damage, or leaks. Pay close attention to critical components such as the engine, hydraulic system, brakes, and tires.
Fluid Checks: Monitor fluid levels regularly, including engine oil, hydraulic fluid, coolant, and brake fluid. Top up fluids as needed and ensure they are at the recommended levels to maintain optimal performance.
Filter Maintenance: Replace air, fuel, oil, and hydraulic filters according to the manufacturer’s recommendations. Clean filters or replace them when they become clogged to prevent contaminants from entering the system.
Lubrication Schedule: Follow the lubrication schedule outlined in the operator’s manual to grease all necessary lubrication points. Proper lubrication reduces friction, extends component lifespan, and ensures smooth operation.
Tire Care: Inspect tires for wear, cuts, and punctures regularly. Maintain proper tire pressure to optimize traction, stability, and fuel efficiency. Rotate tires periodically to promote even wear and prolong tire life.
Cooling System Maintenance: Keep the radiator and cooling system clean and free from debris to prevent overheating. Check hoses, belts, and the radiator core for leaks or damage and replace them as needed.
Electrical System Check: Inspect wiring harnesses, connectors, and battery terminals for corrosion or damage. Test electrical components regularly to ensure they are functioning correctly, including lights, gauges, and warning indicators.
Operator Training: Provide comprehensive training to operators on equipment operation, safety procedures, and maintenance tasks. Well-trained operators can detect issues early, operate equipment safely, and perform basic troubleshooting.
Documentation: Maintain detailed records of all maintenance activities, including inspections, repairs, and parts replacements. Documenting maintenance tasks helps track the history of the loader and ensures timely servicing.
Professional Service: For complex repairs or maintenance tasks beyond your expertise, rely on authorized John Deere service centers or trained technicians. Professional servicing ensures that repairs are done correctly and according to manufacturer standards.

From the convenient controls that customize machine operation to the comfortable fully adjustable air-ride armchair, the Jhon Deere 644J has everything your operators need to do their best.

All-around visibility is unobstructed, and an improved ventilation system helps keep the view clear and the cab environment.

comfortable. The all-new sealed switch module allows convenient fingertip control of multiple machine operations. Up-front, a state-of-the-art multi-function monitor with easy-to-read messaging, large analog gauges, and LED warning lights to provide vital operating info at a glance.

1. Industry-leading 360-degree visibility gives a clear sight lines of the work ahead and the worksite around you.

2. Advanced programmable monitor with analog gauges and LED indicators provide:

A. Vital and general operating information including transmission mode, gear, engine
rpm, and ground speed.

B. Diagnostic readings of most sensors and switches, enabling technicians to quickly troubleshoot problems.

C. Customized machine settings that let an operator match the 644J’s operating characteristics to specific applications by preselecting transmission functions such as Quick Shift and Auto-to-1st for maximum productivity.