________________________________________________________________________________

John Deere 4066R Troubleshooting

John Deere 4066R Diesel Engine Troubleshooting

Engine starts hard or will not start: Fuel filter element is clogged. Filter maintenance required. Air trapped in fuel system. Bleed air. Faulty fuel injection nozzles. If necessary, replace with a new nozzle. Fuel injection pump malfunctioning. Change or repair the pump.

Engine stops running suddenly: Fuel injection pump timing is wrong. Set up as recommended. Fuel filter element is clogged. Change the filter element. Low coolant temperature. Warm up engine as required.

Engine starts but stalls suddenly: Fuel filter element is clogged. Filter maintenance required. Defective fuel injection pump. Replacement or repair required. Air filter plugged. Replace air filter element.

Engine overheats: Clogged radiator fins or leaking radiator cap. Change cap or clean radiator. Engine coolant is insufficient. Add coolant fluid to cooling system and also check it for leaks. Loose or damaged fan belt. Replace as required. Lack of engine oil. Check and refill engine oil.

Engine loses power: Faulty or dirty injection nozzles. Clean or replace injection nozzles. Dirt in the fuel lines or hoses. Service fuel hoses and lines. Air cleaner is dirty. Replace air filter element. Cylinder head gasket is damaged. Install a new gasket.

Engine knocks or noises: Engine is not warmed up to the required temperature. Warm up engine as required. Engine oil level low. Checking oil level and add if necessary. Wrong setting of fuel injection pump timing. Adjust as recommended. Scored or worn pistons. Pistons replacement required. Connecting rod is misaligned or worn. Alignment procedure or replacement is required.

Engine stops while idling: Incorrect low idle speed adjustment. Adjust low idle speed. Excessive valve clearance. Adjust valve clearance according to specifications. Fuel injection pump is faulty. Change pump or rebuild it.

Oil pressure too low: Insufficient engine oil. Fill crankcase to proper oil level. Oil pump is damaged. Remove and inspect oil pump. Clogged oil filter. Change or service engine oil filter.

John Deere 4066R Transmission Troubleshooting

Transmission is excessively noisy: Gears are defective or backlash is improper. Replace defective gears or set backlash properly. Worn or bent gear shift forks. Shift forks need to be replaced. Shaft splines are damaged or worn. Shaft need to be changed. Insufficient transmission fluid. Check and refill the transmission fluid. Worn or broken bearings. Bearings replacement required. Transmission oil contamination. Transmission oil change required.

Difficult to shift gears: Corroded or worn gear shift linkage. Replace or lubricate the shift linkage. Clutch is faulty or misadjusted. Adjust clutch or replace if required. Worn or bent gear shift forks. Change the shift forks. Worn gear shifting mechanism. Repair or change worn components if necessary.

Insufficient transmission oil pressure: Transmission oil level is low. Fill the transmission housing to proper oil level. Clogged transmission oil filter element (if fitted). Service or replace the transmission oil filter. Stuck relief valve. Change relief valve.

Transmission fluid leaks: Damaged gaskets or seals. Seals and gaskets replacement required. Transmission fluid level is high. Correct the fluid level.

Hydrostatic Transmission Troubleshooting

HST transmission makes excessive noise: Worn or out of adjustment speed control linkage. Adjust or replace linkage. Transmission is under excessive load. Reduce loading. Fluid is contaminated or fluid level is insufficient. Fill to required level or change the fluid. Defective relief valve. Replace relief valve as required. Defective or worn transmission parts. Check hydrostatic transmission components for defect or damage and change if necessary.

Transmission fluid overheated: Transmission is under excessive load. Load needs to be reduced. Clogged or damaged cooling components. Check all cooling components and change or repair if required. Insufficient transmission fluid. Need to add transmission fluid. Dirty transmission fluid filter element. Replace or service transmission fluid filter.

Low power: Transmission fluid level is low. Checking transmission fluid level and add if necessary. Relief valve malfunction. Replace the valve. Speed control linkage is defective or unadjusted. Adjust or repair linkage.

External fluid leaks: Oil return tube is plugged. Clean or replace the tube. Worn seals or gaskets. Gaskets or seal replacement required. Transmission case internal pressure is too high. Change defective parts.

John Deere 4066R Hydraulics Troubleshooting

Hydraulic system is overheated: Incorrect hydraulic oil type. Use the correct type of hydraulic oil. Hydraulic oil is dirty. Hydraulic oil change required. Air in the hydraulic system. Air bleeding. Main relief valve failure. Relief valve replacement required.

Insufficient hydraulic oil pressure: Insufficient hydraulic fluid. Add fluid as required. Clogged hydraulic fluid filter element. Change hydraulic filter element or clean if necessary. Leaking hydraulic pipes. Inspect the system for leaks and fix it. Not adjusted hydraulic control valve. Need to adjust. Hydraulic pump not working. Install a new hydraulic oil pump. Hydraulic cylinder not working. Change or repair hydraulic cylinder.

3-point hitch won't lift or lifts slowly: Faulty hydraulic pump. Change or repair hydraulic fluid pump. Main relief valve malfunction. Relief valve replacement required. Faulty hydraulic control valve. Repair or change hydraulic valve. Defective hydraulic cylinder. Repair or change hydraulic cylinder. Hydraulic fluid is insufficient. Fill up the hydraulic fluid. Clogged hydraulic fluid filter element. Change the hydraulic filter element or service if required. Excessive load on hitch. Reduce hitch load.

3-point hitch won't lower or lowers slowly: Hydraulic cylinder is broken. Change or repair hydraulic cylinder. Incorrect setting hydraulic spool valve. Use the correct setting. Hitch rock shaft is worn. Replace the shaft. Misadjusted hitch. Adjust the 3-point hitch.

Hitch jerks when drop or lift: Dirty hydraulic oil. The oil must be changed. Hydraulic pump is faulty. Change or repair hydraulic fluid pump. Air in hydraulic system. Bleed air from hydraulic system. Defective hydraulic spool valve. Change or repair hydraulic valve. Faulty hydraulic cylinder. Replace or repair hydraulic cylinder.

John Deere 4066R Steering Troubleshooting

Steering wheel free play is excessive: Steering column shaft or coupling is worn out. Change defective part. Steering pump not working. Install a new hydraulic steering pump. Steering linkage joints are worn or loose. Replace or repair steering linkage. Power steering control unit has malfunction or wear. Repair or replace the steering unit.

Hard Steering: Air in the hydraulic steering system. Bleed air. Steering filter is dirty. Clean steering filter element. Steering oil level low. Add oil to steering system. Power steering control unit has wear or damage. Replace or repair power steering control unit as required. Steering pump not working. Install a new steering pump. Damaged or stuck steering pump control valve. Replace or clean flow control valve. Improperly fitted or damaged steering column. Refit or change the steering column. Uneven tire pressure. Inflate the tires properly. Incorrect toe-in. Adjust toe-in properly. Steering cylinder leaks. Replace scratched piston rod or worn cylinder seals.

Front wheels wander to left or right: Power steering control unit has malfunction or wear. Inspect and replace as required. Steering cylinder damage. Replace or repair hydraulic steering cylinder. Incorrect toe-in. Check toe-in and correct. Steering linkage joints are worn or loose. Replace or repair steering linkage. Incorrectly adjusted or worn front wheel bearings. Install new bearings or adjust it correctly. Tire pressure is uneven. Adjust the tire pressure.

John Deere 4066R Electrical Troubleshooting

Battery cannot be charged: Corroded or loose cable connections. Service or tighten connections. Defective battery terminal clamps. Install new terminal clamps. Bad cell in battery. Battery change required. Worn or loose belt. Adjust belt tension or change the belt.

Starter turns slowly: Low battery output voltage. Battery is drained, recharge it. Battery runs out quickly. Service or change the battery. Disconnected wiring or bad battery terminals. Connect cables correctly or replace terminals.

Starter will not crank: Battery is discharged or worn. Recharge or change battery. Wiring is incorrectly connected or disconnected. Inspect wiring and connect correctly. Battery voltage is low. Charge the battery. Faulty starter motor. Repair or change starter.

JOHN DEERE TRACTORS ATTACHMENTS
1023E	2025R	2210	2520	3032E
3046R	3520	4066R	4105	4200
4320	4400	4520	4600	4720
430	420	455	X300	X350
X485	X500	X590	X700	X738

JOHN DEERE TRACTORS TROUBLESHOOTING
2640	3040	3310	3650	4100
5050D	5090R	5410	6105R	7200R
E130	L111	LA110	LT155	X300R