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John Deere 444K Troubleshooting

The John Deere 444K wheel loader driveline system components: 276 cu.in (4.5L) John Deere PowerTech E 4045H 4-cylinder direct injection turbocharged diesel engine with a rated power of 124 hp (92 kW), and 4x3 powershift transmission with torque converter. The hydraulic system has a pump with a rated capacity of 23.5 gal/min (80 l/min). The John Deere 444K is equipped with a power steering system, hydraulic wet multi-disc brakes, and 17.5R25 tires. The wheel loader has a maximum lift height of 141.7" (3600 mm) and breakout force of 17550 lbs (7960 kg). The rated operating capacity is 8200 lbs (3720 kg), and tipping load is 16400 lbs (7440 kg).

Engine Troubleshooting

Engine starts hard or won't start
Air in fuel tank - Bleed fuel tank.
Fuel filter element is dirty - Filter maintenance required.
Dirty or damaged injection nozzles - Inspect nozzles and replace if necessary.
Water in the fuel system - Change fuel and repair fuel system.
Incorrect valve clearance - Adjust valve clearance.
Fuel injection pump is not operating properly - Repair or change injection pump.

Diesel starts but then stops
Plugged air cleaner - Clean or replace element.
Fuel filter element clogging - Replace filter element.
Fuel injection pump leakage - Check the fuel injection pump for leaks and fix it.
Fuel injectors are dirty or defective - Replace or clean fuel injectors.
Fuel injection pump is broken - Repair or change injection pump.

Diesel shuts off while driving
Engine is not preheated - Warm up to required temperature.
Fuel filter element is dirty - Clean the filter or install new filter element.
Air in the fuel pipes - Bleed the fuel pipes.
Fuel injection nozzles are clogged or faulty - Service or change injection nozzles.
Improper setting of fuel injection pump timing - Check the fuel injection pump timing adjustment.

Engine stops at low idle speed
Wrong adjustment of low idle speed - Normalize low idle speed.
Faulty fuel injection pump - Replacement or repair required.
Clogged or defective injectors - Change or clean fuel injectors.
Incorrect valve clearance - Check and adjust as required.

Low engine power
Air cleaner is clogged - Clean or replace air cleaner element.
Fuel injection nozzles are faulty or clogged - Change fuel injection nozzles.
Improper fuel injection pressure - Adjust to correct pressure.
The valve clearance is incorrect - Adjust valve clearance according to specifications.
Low idle speed setting is not correct - Correct the settings.
Restricted fuel lines or hoses - Service fuel hoses and lines.
Cylinder head gasket is defective - Install a new gasket.
Piston rings are broken or leaking - Change piston rings.

Engine overheated
Not enough coolant - Fill the cooling system and check components for leaks or other faults.
Low engine oil level - Fill up the engine oil.
Radiator core is clogged or radiator cap is leaking - Clean radiator or change cap.
Fan belt is loose or defective - Belt change is required.
Diesel engine is overloaded - Load reducing is recommended.

Insufficient oil pressure
Low oil level - Fill up the engine oil.
Clogged oil filter - Replace or service engine oil filter.
Incorrect oil viscosity - Use the specified type of engine oil.
Incorrect crankshaft bearing oil clearance - Bearing needs to be changed.
Worn oil pump - Repair or change.

Engine noise or knocking
Engine oil level is low - Need to add engine oil.
Engine is not fully warmed up - Warm up to required temperature.
Improper setting of fuel injection pump timing - Adjust fuel injection pump as required.
Low idle speed adjustment is incorrect - Adjust as required.
Fuel injectors are dirty or defective - Clean fuel injectors or change it.
Connecting rod is defective or not aligned - Replace or align connecting rod.
Pistons are broken or worn - Pistons need to be replaced.

Transmission Troubleshooting

Low transmission oil pressure
Transmission oil insufficient - Add oil to the transmission housing.
Clogged transmission oil filter element (if fitted) - Clean or replace the transmission filter.
Defective relief valve - Replace the valve.

Transmission is excessively noisy
Low fluid level - Fill the transmission housing to proper fluid level.
Transmission fluid contamination - Transmission fluid change required.
Worn gears or incorrect backlash - Replace defective gears or set backlash properly.
Worn or cracked bearings - Install new bearings.
Shift forks are bent or worn out - Install new shift forks.
Worn or stuck shaft splines - Replace the shaft.

Difficulty shifting gears
Worn or rusty gear shift linkage - Replace or lubricate the shift linkage.
Shift forks are worn or bent - Replace defective shift forks.
Gearshift mechanism is damaged - Replace or repair the mechanism.
Unadjusted or worn clutch - Adjust or replace the clutch.

Transmission fluid leakage
Transmission oil level is high - Correct the oil volume.
Seals or gaskets are broken - Replace worn gaskets or seal.

Hydraulics Troubleshooting

Hydraulic system overheats
Hydraulic pressure incorrectly adjusted - Adjust it correctly.
Unadjusted or defective main relief valve - Adjust relief valve or change if required.
Hydraulic fluid is contaminated - The fluid must be changed.
Lack of hydraulic oil - Fill up the hydraulic oil.
Defective hydraulic pump - Repair or replace pump if necessary.

Boom cannot be lowered or raised
Lift controls are damaged - Change or repair.
Hydraulic pump failure - Install new pump or repair it.
Faulty hydraulic control valve - Change or repair hydraulic valve.
Defective hydraulic cylinder - Change or repair lift cylinder.
Insufficient hydraulic fluid - Checking hydraulic fluid level and add if necessary.

Bucket does not function
Damaged bucket controls - Change or repair.
Hydraulic pump malfunction - Repair or replace pump if necessary.
Faulty hydraulic control valve - Repair or change hydraulic valve.
Bucket cylinder is faulty - Change or repair cylinder.
Insufficient hydraulic fluid - Fill up the hydraulic fluid.

Bucket or lift arm runs slowly
Hydraulic pump is defective - Check pump flow and install new pump if necessary.
Leaking hydraulic cylinder - Replace cylinder piston seals.
Insufficient hydraulic oil - Check and refill the hydraulic oil.
Hydraulic control valve is unadjusted or worn - Repair or set properly.
Hydraulic system loosing pressure - Set pressure correctly.

Bucket or boom is jerky
Air trapped in hydraulic system - Need to bleed air.
Clogged hydraulic oil filter element - Service or replace the hydraulic filter.
Hydraulic fluid is dirty - The fluid must be changed.
Scratched cylinder rod or tube - Replace defective component.

Hydraulic pump is excessively noisy
Leaking hydraulic system or insufficient oil level - Top up hydraulic oil or remedy leakage in system.
Hydraulic filter clogging - Clean or change the filter.
Suction line clogging - Suction line needs to be cleaned.
Pump is sucking air - Bleed air.
Faulty pump components - Rebuild or change hydraulic pump.

Electrical Troubleshooting

Battery does not charge
Wiring connections are corroded or loose - Clean or tighten wiring connections.
Battery terminal clamps are defective - Terminal clamps should be changed.
Battery faulty cell - Battery replacement required.
Defective or loose belt - Install a new belt or adjust belt tension.

Starter turns slow
Low battery output - Battery needs to be recharged.
Battery is draining quickly - Service battery or replace it.
Battery terminals are corroded or wires are disconnected - Connect wires properly or change terminals.

Starter is not cranking
Battery is low or faulty - Recharge or replace battery.
Wiring is improperly connected or disconnected - Check wiring and connect properly.
Low battery voltage - Battery needs to be recharged.
Starter motor is faulty - Repair or install a new starter.

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WHEEL LOADERS SPECIFICATIONS

Caterpillar