________________________________________________________________________________________
John Deere 4020 Troubleshooting
The
John Deere 4020 is a 4x2 New Generation series row-crop tractor. This model was
manufactured from 1963 to 1972. The components of JD 4020 driveline system: The
John Deere 6-cylinder gasoline or diesel engine, and 8x4 Syncro Range partially
synchronized transmission or 8-speed full power shift transmission. Max.
forward speed - 20.5 mph (33 kph), max. reverse speed - 5.2 mph (8.4 kph).
The closed center hydraulic system includes a piston pump with fluid
flow rate of 18 gpm (68.1 lpm). The main relief pressure is 2250 psi (155
bar). The rear lift capacity is 3790 lbs (1720 kg).
The John Deere 4020 tractor fitted with standard 7.5x18 front tires
and 18.4x34 rear tires, or row-crop 6.00x16 front tires and 15.5x38 rear
tires. The wheelbase is 100.3" (2540 mm) for standard models and 97.5"
(2470 mm) for row-crop models. The John Deere 4020 is compatible with
JD 148 front end loader with a maximum lift height of 126" (3200 mm), and
JD 158 front end loader with a maximum lift height of 156" (3960 mm).
| Diesel Engine Troubleshooting |
| Diesel won't start or hard to start |
| Fuel filter is dirty - Change the filter element |
| The fuel shut-off valve is closed - Open fuel shut-off valve |
| Air trapped in fuel system - Bleed air |
| Dirty or damaged injectors - Service or change fuel injectors |
| Fuel injection pump is defective - Repair or replace injection pump |
| Bad engine compression - Inspect cylinder block and replace worn components |
| Engine stalls during operation |
| Engine has not warmed up to the recommended temperature - Warm up the engine |
| Air in fuel pipes - Bleed fuel pipes |
| Irregular fuel injection - Adjust fuel injection timing |
| Plugged fuel filter - Service or replace the filter |
| Fuel injectors are damaged or dirty - Change fuel injectors |
| Engine starts and stalls immediately |
| Fuel injection pump out of timing - Adjust the fuel injection pump timing correctly |
| Dirty fuel filter element - Install new filter element |
| Clogged or defective injector nozzles - Check and change nozzles as required |
| Fuel injection pump is not operating properly - Repair or change injection pump |
| Air cleaner element is dirty - Change or replace air cleaner element |
| Low idle speed setting is incorrect - Correct low idle settings |
| Fuel injection pump is not working correctly - Replace or rebuild injection pump |
| Clogged or damaged injector nozzles - Change or clean injector nozzles |
| Valve clearance is out of adjustment - Have it adjusted |
| Engine coolant is insufficient - Fill radiator to proper level. Any leaks must be repaired |
| Cooling system parts are damaged or system is dirty - Replace faulty parts or flush the cooling system |
| Low engine oil level - Fill the crankcase with engine oil |
| Damaged fan belt or incorrect belt tension - Adjust belt tension properly or replace it |
| Defective thermostat - Check and replace if required |
| Fuel injectors are clogged or faulty - Inspect fuel injectors and replace if necessary |
| Improper fuel injection pressure - Check the fuel injection pressure and adjust if necessary |
| Dirty air filter element - Replace filter or install new filter element |
| Clogged oil filter - Clean or replace engine oil filter element |
| Engine is overloaded - Load reducing required |
| Valve clearance is out of adjustment - Correct valve clearance |
| Low idle speed setting is incorrect - Correct low idle adjustment |
| Fuel pipes or hoses are clogged - Clean fuel pipes and hoses |
| Lack of compression: Valves are defective or worn - Replace the valves |
| Incorrect setting of fuel injection pump timing - Repair or replace fuel injection pump |
| Clogged or defective injector nozzles - Install new set of properly balanced nozzles |
| Engine oil level low - Fill up the oil to required level |
| Engine is not fully warmed up - Engine is not warmed up to the required temperature |
| Main bearings or crankshaft wear - Install new parts |
| Broken or worn piston rings - Piston rings replacement required |
| Flywheel mounting screws are loose - Tighten the screws |
| Diesel engine consuming too much oil |
| Oil leaks: Damaged seals or gaskets - Worn parts need to be replaced |
| Incorrect oil viscosity - Use correct viscosity oil |
| Piston rings are seized or worn - Piston rings need to be replaced |
| Valve guides or stems are damaged - Valves replacement required |
| Cylinder liners or pistons are damaged - Check liners and pistons, replace as required |
| Electrical System Troubleshooting |
| Battery cannot be charged |
| Faulty cell in battery - Install a new battery |
| Damaged battery wiring harness - Inspect wiring for damage, replace or repair |
| Loose or corroded cables and terminals - Tighten or service cables and terminals |
| Belt is damaged or belt tension is incorrectly adjusted - Change belt or adjust belt tension properly |
| Battery voltage is low - Battery is drained, recharge it |
| Battery does not hold charge - Service charging system or replace battery |
| Bad battery wiring harness - Inspect wiring for malfunctions, replace or repair |
| Battery cables and terminals are corroded or loose - Clean or tighten cables and terminals |
| Battery voltage is low - Low battery charging, charge as required |
| Drained or worn battery - Recharge or change battery |
| Starter motor is damaged - Starter should be replaced |
| Disconnected or incorrectly connected cables - Need to reconnect cables correctly |
| Transmission Troubleshooting |
| Gear hard to shift |
| Worn or incorrectly adjusted clutch - Adjust correctly or replace |
| Gear shift linkage is stuck or worn - Service or change the shift linkage |
| Shift forks are worn or damaged - Change the shift forks |
| Gearshift mechanism failure - Change or repair failed components |
| Transmission fluid pressure is insufficient |
| Low transmission fluid level - Fill up the transmission fluid |
| Transmission oil filter clogging (if fitted) - Change or clean the transmission oil filter |
| Damaged relief valve - Change relief valve |
| Transmission is excessively noisy |
| Bearings are worn or damaged - Replace faulty bearings |
| Oil level is low - Check transmission oil level and add oil as required |
| Transmission fluid contamination - Fill up with fresh transmission fluid |
| Worn gears or improper backlash - Change damaged gears or adjust backlash properly |
| Damaged or worn shift forks - Replace the shift forks |
| Broken gaskets or seals - Seals and gaskets replacement required |
| Transmission case is cracked - Replace case or transmission assembly |
| Hydraulics Troubleshooting |
| Excessive hydraulic system heat |
| Hydraulic system pressure is not set correctly - Set the hydraulic pressure as required |
| Unadjusted or defective main relief valve - Adjust the valve or replace if necessary |
| Hydraulic oil contamination - Change the oil |
| Aeration in hydraulic system - Check the pump seals, suction pipe, and fittings |
| Hydraulic oil pressure is insufficient |
| Hydraulic fluid level is low - Need to add fluid |
| Hydraulic fluid filter element is dirty - Clean or change hydraulic filter |
| Hydraulic pump is defective - Test the pump flow rate and change pump if required |
| Hydraulic control valve block is faulty or out of adjustment - Set properly or replace |
| Hydraulic cylinder is faulty - Check the cylinder components for damage or wear and change if necessary |
| Hydraulic piping leaks - Identify leaks in the system and repair it |
| Hitch cannot be lifted or lifting is too slow |
| Lack of hydraulic fluid - Check and refill the hydraulic fluid |
| Hydraulic oil is too cold - Allow oil to warm |
| Hydraulic fluid filter is dirty - Hydraulic filter maintenance required |
| Hydraulic pump is defective - Test the pump flow rate and change pump if required |
| Misadjusted or defective main relief valve - Adjust the valve or replace if necessary |
| Hydraulic spool valve is defective or set improper - Change or adjust correctly |
| Hydraulic cylinder is faulty - Check the hydraulic cylinder parts for damage or wear and replace if necessary |
| Damaged or loose suction line - Tighten or change |
| 3-point hitch fails to drop or drops slowly |
| Defective or incorrect setting hydraulic control valve block - Adjust properly or change |
| Hydraulic cylinder is defective - Inspect the hydraulic cylinder parts for damage or wear and replace if required |
| Worn hitch rock shaft - Install a new shaft |
| Defective mechanical parts of the hitch - Replace worn or faulty hitch parts |
| Jerky lowering or lifting of the hitch |
| Air trapped in the hydraulic system - Inspect the pump seals, suction line, and fittings |
| Dirty hydraulic oil - The oil must be changed |
| Hydraulic pump is defective - Check pump capacity and change if necessary |
| Defective or not adjusted hydraulic control valve - Change or adjust correctly |
| Faulty hydraulic cylinder - Check cylinder components for wear or damage and change if necessary |
| Steering System Troubleshooting |
| Difficult steering |
| Steering column is broken or incorrectly fitted - Steering column needs to be refit correctly or replaced |
| Air trapped in the steering system - Bleed air |
| Improper toe-in adjustment - Adjust toe-in properly |
| Tires are incorrectly inflated - Inflate as required |
| Steering pump stopped working - Install a new steering pump |
| Steering valve assembly is damaged or worn - Replace or repair steering valve as required |
| Damaged steering valve cylinder parts - Replace defective components of steering valve cylinder |
| Steering fluid level low - Checking steering fluid level and add it if necessary |
| Oil leakage in the steering system - Retighten joints of the hydraulic steering pipes and hoses |
| Excessive free play of steering wheel |
| Steering column shaft or coupling has maximum wear - Replace defective part |
| Steering valve assembly is defective or worn - Repair or change the steering valve |
| Damaged steering valve cylinder parts - Defective steering valve cylinder components must be replaced |
| Steering pump not working - Repair or replace steering pump |
| Steering linkage or tie-rod ends are defective - Replace failed component |
| Tractor pulls to left or right |
| Tire pressure is improper - Inflate the tires properly |
| Improper toe-in adjustment - Adjust toe-in wheels properly |
| Faulty or worn steering tie-rod ends or linkage - Change damaged part |
| Faulty or worn steering valve assembly - Inspect and replace as required |
| Steering valve cylinder is faulty - Change or repair steering valve cylinder |
| Front hub bearings are worn or incorrectly adjusted - Adjust properly or change bearings |
________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
| Farm Tractors Technical Specifications |
