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Home / Wheel Loaders / John Deere Wheel Loaders / John Deere 444G

John Deere 444G Troubleshooting

The John Deere 444G wheel loader is powered by John Deere 4045T vertical in-line four-cylinder direct injection turbocharged diesel engine with a rated power of 100 hp (74 kW) at 2350 rpm. The John Deere 444G is equipped with a two-range hydrostatic transmission, power steering system, hydraulic wet disc brakes, and 17.5x25 or 15.5x25 tires. The hydraulic system has a pump with fluid flow rate of 35.9 gpm (136 lpm). The wheel loader has a rated operating capacity of 6645 lbs (3020 kg) and tipping load of 13290 lbs (6040 kg). The maximum lift height is 139 inches (3530 mm) to hinge pin, and boom breakout force is 16170 lbs (7350 kg).

Engine Troubleshooting

Engine starts hard or will not start
There is air in the fuel system - Bleed the system.
Fuel filter element is dirty - Clean or replace the filter.
Fuel injection nozzles are clogged or faulty - Change fuel injection nozzles.
Water or dirt in fuel system - Drain, flush, and service the system.
Valve clearance is not correct - Have it adjusted.
Defective fuel injection pump - Replace injection pump or repair it.

Diesel starts but immediately shuts off
Plugged air filter - Service or replace the air filter.
Clogged fuel filter - Install new filter element.
Fuel injection pump has loose connections - Tighten the connections.
Fuel injectors are dirty or defective - Test and replace fuel injectors if necessary.
Fuel injection pump malfunction - Rebuild or install a new injection pump.

Engine stops running suddenly
Engine not warmed up - Warm up engine as required.
Fuel filter is plugged - Service or replace the filter.
Air in the fuel lines - Bleed the fuel lines.
Faulty fuel injection nozzles - Clean or change injection nozzles.
Improper setting of fuel injection pump timing - Adjust according to specifications.

Engine stops at low idle speed
Low idle speed setting is not correct - Correct low idle settings.
Fuel injection pump failure - Change pump or rebuild it.
Clogged or defective injectors - Change or clean fuel injectors.
Valve clearance is wrong - Adjustment procedure required.

Engine lacks power
Clogged air filter - Service or replace the air filter.
Fuel injection nozzles fault - Inspect nozzles and replace if necessary.
Insufficient fuel injection pressure - Adjust pressure to proper level.
The valve clearance is incorrect - Have it adjusted.
Too low idle RPM - Adjust low idle speed.
Fuel lines or hoses clogging - Clean fuel system hoses and lines.
Damaged cylinder-head gasket - Install a new gasket.
Worn or broken piston rings - Change piston rings.

Engine overheated
Coolant level is low - Top up coolant fluid and check system for leaks.
Engine oil level is low - Need to add engine oil.
Clogged radiator fins or leaking radiator cap - Install new cap or clean radiator.
Fan belt is broken or worn - Replace as required.
Engine overload - Load reducing required.

Oil pressure is low
Lack of oil - Check and refill the oil.
Plugged engine oil filter - Replace or clean engine oil filter element.
Wrong oil viscosity - Use the specified type of engine oil.
Incorrect oil clearance in main bearing - Bearings need to be reinstalled.
Oil pump is damaged - Check and replace if necessary.

Abnormal engine noise or knocking
Engine oil level low - Check and refill engine oil.
Coolant temperature is low - Warm up engine as required.
Timing of fuel injection pump is incorrect - Adjust fuel injection pump as required.
Low idle speed setting is incorrect - Correct low idle settings.
Dirty or defective injectors - Clean or replace fuel injectors.
Connecting rod is defective or misaligned - Need to align or replace the connecting rod.
Pistons are scored or worn - Pistons need to be replaced.

Hydrostatic Transmission Troubleshooting

Hydrostatic transmission noises
Transmission fluid is dirty or fluid level is too low - Add fluid to the correct level or fill the transmission with fresh fluid.
Speed control pedal linkage is damaged or out of adjustment - Adjust or repair linkage.
Relief valve is stuck - Replace relief valve.
Transmission overload - Reduce transmission load.
Transmission components are damaged or worn - Check internal transmission parts for damage or wear and replace if required.

Low power
Insufficient transmission fluid - Fill the transmission housing to proper fluid level.
Defective relief valve - Install a new valve.
Speed control pedal linkage is bent or not adjusted - Adjust or repair linkage.

Transmission oil over heats
Low oil level - Check transmission oil level and add oil as required.
Dirty transmission oil filter element - Clean or replace the transmission filter.
Cooling components are clogged or damaged - Inspect all cooling components and replace or clean if necessary.
Transmission overload - The load should be reduced.

Transmission oil leaking
Broken seals or gaskets - Gaskets or seal replacement required.
Transmission case internal pressure is too high - Change defective components.
Oil return tube is plugged - Clean or replace the tube.

Hydraulics Troubleshooting

Hydraulic system has overheating
Hydraulic pressure is not correct - Hydraulic pressure must be set correctly.
Main relief valve failure or improper setting - Replace or set up the relief valve.
Contaminated hydraulic oil - Fill up with fresh hydraulic oil.
Hydraulic oil level is low - Add oil to the hydraulic system.
Hydraulic pump is faulty - Replace or repair pump if necessary.

Boom can't lift or drop
Lift controls malfunction - Inspect and repair if necessary.
Hydraulic pump not working - Repair or replace pump if necessary.
Defective hydraulic control valve - Repair or change the valve.
Hydraulic cylinder is defective - Repair or replace hydraulic cylinder.
Hydraulic fluid is insufficient - Checking hydraulic fluid level and add if necessary.

Bucket can't tilt
Bucket tilt controls malfunction - Inspect and repair if necessary.
Hydraulic pump malfunction - Repair or install new hydraulic pump.
Hydraulic control valve is faulty - Repair or change the valve.
Bucket cylinder is faulty - Repair or change cylinder.
Low hydraulic fluid level - Checking hydraulic fluid level and add if necessary.

Slow bucket or lift arm action
Hydraulic pump is defective - Test pump performance and replace pump if necessary.
Leaking hydraulic cylinder - Repair leak by replacing the seals.
Insufficient hydraulic fluid - Checking hydraulic fluid level and add if necessary.
Hydraulic control valve is faulty or out of adjustment - Repair or adjust correctly.
Low hydraulic pressure - Adjust pressure correctly.

Bucket or boom is moving jerkily
Air in hydraulic system - Bleed air from hydraulic system.
Clogged hydraulic oil filter element - Clean or install new filter.
Hydraulic oil contamination - The oil must be changed.
Cylinder tube or rod scoring - Change failed component.

Hydraulic pump makes excessive noise
Lack of oil or hydraulic leakage - Correct hydraulic leaks or top up oil as needed.
Hydraulic filter is clogged - Clean or change the filter.
Suction line clogging - Suction line must be serviced.
Pump sucks air - Need to bleed air.
Pump components are damaged - Change or rebuild pump.

Electrical Troubleshooting

Battery does not charge
Loose or corroded cable connections - Service or tighten connections.
Battery terminal clamps are defective - Replace terminal clamps.
Battery faulty cell - Battery change required.
Defective or loose belt - Belt needs to be adjusted or changed.

Starter cranks slowly
Battery capacity is low - Battery needs to be recharged.
Battery runs out quickly - Service charging system or change battery.
Battery cables are disconnected or terminals are faulty - Check wiring connections and replace or clean terminals.

Starter does not work
Battery is drained or worn - Charge or replace the battery.
Wiring is improperly connected or disconnected - Check wiring and connect properly.
Battery voltage is low - Low battery charging, charge as required.
Starter motor is damaged - Starter needs to be replaced.

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WHEEL LOADERS SPECIFICATIONS

Wheel Loaders, Skid Steers, and Compact Track Loaders