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New Holland 6635 Troubleshooting

New Holland 6635 Engine Troubleshooting

Engine starts up hard or won't start: Fuel filter plugged. Change filter element. Air in the fuel lines. Bleed the fuel lines. Fuel injection nozzles are damaged or dirty. Test injection nozzles and change if necessary. Fuel injection pump damage. Repair or change injection pump.

Engine shuts off while running: Fuel injection pump timing is wrong. Set the fuel pump timing correctly. Clogged fuel filter. Clean or replace the filter. Low coolant temperature. Warm up engine as required.

Diesel starts but immediately stops: Fuel filter element clogging. Install new filter element. Faulty fuel injection pump. Replace injection pump or repair it. Dirty air cleaner. Replace air filter element.

Engine is overheated: Clogged radiator core or leaking radiator cap. Clean radiator or replace cap. Coolant level is low. Fill radiator to proper level and check components for faults. Loose or defective fan belt. Belt replacement is recommended. Insufficient engine oil. Check oil level and add oil as required.

Engine lacks power: Clogged injection nozzle. Check and replace nozzles if required. Restricted fuel lines or hoses. Clean fuel hoses and lines. Dirty air filter element. Clean air cleaner element. Worn cylinder head gasket. Gasket should be replaced.

Engine noises or knocks: Engine not warmed up. Warm up to required temperature. Engine oil insufficient. Check and refill engine oil. Fuel injection pump timing is not adjusted. Set it up as required. Pistons are broken or worn. Replace the pistons. Connecting rod is not aligned or worn. Replace or align connecting rod.

Engine shuts off while idling: Incorrectly adjusted low idle speed. Adjust low idle speed. Incorrect valve clearance. Adjust valve clearance according to specifications. Fuel injection pump is damaged. Repair or change injection pump.

Oil pressure is insufficient: Oil level is low. Add oil as required. Oil pump failure. Repair or change. Oil filter element clogged. Replace or service engine oil filter.

New Holland 6635 Transmission Troubleshooting

Transmission noise: Incorrect backlash or gears are worn. Adjust backlash correctly or replace the gears. Shift forks are bent or worn out. Shift forks need to be changed. Stuck or worn shaft splines. Change the shaft. Transmission fluid level is low. Need to add transmission fluid. Worn or broken bearings. Replace the bearings. Transmission oil contamination. Change the oil.

Gears are hard to shift: Gear shift linkage is corroded or worn. Shift linkage need to be replaced. Worn or unadjusted clutch. Clutch needs to be adjusted or changed. Worn or damaged gear shift forks. Change defective shift forks. Worn parts of the gear shifting mechanism. Change worn parts.

Lack of transmission oil pressure: Lack of transmission oil supply. Check and refill the transmission oil. Dirty transmission fluid filter (if fitted). Clean or change transmission fluid filter. Defective relief valve. Replace the valve.

Transmission oil leaking: Damaged gaskets or seals. Change defective seal or gaskets. High transmission oil level. Correct the oil level.

New Holland 6635 Hydraulic System Troubleshooting

Hydraulic system is too hot: Wrong hydraulic fluid type. Pour the proper type of fluid. Hydraulic fluid contamination. Change hydraulic fluid. Air in hydraulic pipes. Bleed hydraulic pipes. Faulty main relief valve. Install a new relief valve.

Hydraulic fluid pressure too low: Insufficient hydraulic oil. Check and refill the hydraulic oil. Dirty hydraulic fluid filter element. Clean or replace the hydraulic filter. Hydraulic piping is leaking. Check the hydraulic system and fix leaks. Hydraulic spool valve is out of adjustment. Spool valve adjustment required. Hydraulic pump failure. Replace or repair hydraulic fluid pump. Hydraulic cylinder malfunction. Change or repair hydraulic cylinder.

3-point hitch fails to lift or lifts slowly: Hydraulic pump malfunction. Change or repair hydraulic oil pump. Main relief valve is faulty. Relief valve must be changed. Hydraulic control valve block is damaged. Install a new hydraulic valve or repair it. Hydraulic cylinder not working. Repair or install a new hydraulic cylinder. Low hydraulic oil level. Need to add oil. Clogged hydraulic fluid filter. Clean the hydraulic filter element or replace if necessary. Excessive hitch loading. Reduce hitch load.

3-point hitch won't lower or lowers slowly: Faulty hydraulic cylinder. Replace or repair hydraulic cylinder. Incorrect adjusted hydraulic control valve. Adjust correctly. Lift arm shaft is worn. Install a new shaft. The three-point hitch is not adjusted. Need to make adjustments.

Hitch lift or drop is not smoothly: Hydraulic fluid is dirty. Hydraulic fluid change required. Hydraulic pump is faulty. Install a new hydraulic fluid pump. Air trapped in hydraulic system. Bleed air from system. Hydraulic spool valve block is faulty. Change or repair hydraulic valve. Hydraulic cylinder not working. Repair or change hydraulic cylinder.

New Holland 6635 Steering System Troubleshooting

Excessive steering wheel free play: Steering column coupling or shaft has maximum wear. Change defective component. Steering pump stopped working. Steering pump needs to be replaced or repaired. Worn or loose steering linkage assembly. Check and replace as required. Power steering control valve has damage or wear. Repair or change the steering control valve.

Hard Steering: Air in the hydraulic steering system. Bleed air from system. Dirty steering filter element. Service steering filter. Steering oil level is low. Fill up steering oil to required level. Power steering control valve is damaged or worn. Inspect and change as required. Steering pump malfunction. Steering pump needs to be replaced or repaired. Steering pump control valve is stuck or faulty. Change or flush control valve. Defective or incorrectly mounted steering column. Change steering column or mount correctly. Uneven tyre pressure. Inflate the tyres properly. Incorrect toe-in. Adjust toe-in properly. Steering cylinder leaks. Change damaged piston rod or worn seal sleeves.

Tractor pulls to right or left: Power steering control valve is defective or worn. Repair or replace the steering control valve. Steering cylinder is damaged. Repair or change hydraulic steering cylinder. Incorrect toe-in. Adjust toe-in properly. Loose or worn steering linkage components. Check and change as required. Improperly adjusted or defective front wheel bearings. Replace or adjust the bearings correctly. Uneven tyre pressure. Inflate the tyres properly.

New Holland 6635 Electrical System Troubleshooting

Battery will not charge: Electrical cable connections are corroded or loose. Tighten or clean connections. Defective battery terminal connectors. Terminal connectors should be replaced. Battery bad cell. Change the battery. Belt is loose or defective. Install a new belt or adjust belt tension.

Starter motor cranks slow: Low battery capacity. Battery needs to be recharged. Battery runs out quickly. Service battery or replace it. Disconnected wiring or bad battery terminals. Check cable connections and replace or service terminals.

Starter is not working: Battery is low or faulty. Replace or charge as required. Wire harness is disconnected or incorrectly connected. Check wire harness and connect as required. Low battery voltage. Battery is drained, charge it. Damaged starter motor. Replace or repair starter.