Gehl CTL70 Track Loader Troubleshooting

The Gehl CTL70 compact track loader driveline system components: a 186.7 cu.in (3.1L) Isuzu 4JG1T 4-cylinder direct injection turbocharged diesel engine with a rated power of 81 hp (60.5 kW), and two-speed transmission. The hydraulic system has a pump with a rated flow of 19.8 gpm (75 lpm). The system pressure is 3000 psi (207 bar). The Gehl CTL70 is equipped with a radial-lift loader boom, undercarriage with four steel rollers, and 17.7" (450 mm) rubber tracks. The loader has a boom lift force of 7425 lbs (3370 kg) and bucket breakout force of 7401 lbs (3358 kg). The rated operating capacity is 2083 lbs (945 kg), and tipping load is 5952 lbs (2700 kg).

Engine Troubleshooting

Engine starts hard or will not start

Air in fuel tank - Bleed fuel tank.
Fuel filter plugging - Clean the filter element.
Fuel injection nozzles are faulty or clogged - Test injection nozzles and change if necessary.
Water in the fuel system - Change fuel and repair fuel system.
Improper valve clearance - Adjust valve clearance.
Fuel injection pump malfunction - Replace or repair injection pump.

Diesel starts but stalls suddenly

Air filter is dirty - Replace or clean air filter element.
Fuel filter plugging - Change filter element.
Fuel injection pump has loose connections - Tighten the connections.
Clogged or defective injectors - Change or clean fuel injectors.
Fuel injection pump malfunction - Change or repair the pump.

Engine stops running suddenly

Low coolant temperature - Warm up the engine.
Fuel filter element clogging - Change the filter element.
Air in fuel tank - Bleed fuel tank.
Faulty fuel injection nozzles - Check and replace nozzles if required.
Improper fuel injection timing - Set the fuel pump timing correctly.

Engine stops at low idle speed

Incorrect low idle setting - Adjustment required.
Defective fuel injection pump - Change pump or rebuild it.
Damaged or clogged injectors - Test and replace fuel injectors if necessary.
Valve out of adjustment - Adjust valve clearance according to specifications.

Diesel engine is losing power

Air filter is clogged - Service or replace the air filter.
Dirty or damaged injection nozzles - Replace injection nozzles.
Fuel injection pressure is wrong - Test fuel injection pressure and adjust it correctly.
Valve clearance is wrong - Check and adjust as required.
Low idle speed setting is incorrect - Correct the settings.
Fuel hoses or lines are dirty - Clean fuel hoses and lines.
Blown cylinder head gasket - Gasket should be replaced.
Piston rings are worn or defective - Install new piston rings.

Engine overheating

Low coolant level - Top up coolant fluid and check system for leaks.
Engine oil insufficient - Check and refill engine oil.
Radiator fins are dirty or radiator cap is defective - Clean radiator or replace cap.
Excessive wear of the fan belt - Belt replacement is recommended.
Engine is under excessive load - Reduce load on the engine.

Insufficient oil pressure

Lack of oil - Fill up the engine oil.
Clogged oil filter - Service or change engine oil filter element.
Different type of engine oil - Drain crankcase and refill with correct oil.
Main bearing oil clearance is excessive - Change bearings.
Oil pump failure - Check and replace if necessary.

Abnormal engine knocking or noise

Insufficient engine oil - Need to add engine oil.
Low coolant temperature - Warm up the engine.
Improper setting of fuel injection pump timing - Use the correct fuel injection pump timing adjustment.
Low idle speed setting is not correct - Adjustment required.
Damaged or clogged injectors - Clean or replace fuel injectors.
Connecting rod is not aligned or defective - Alignment procedure or replacement is required.
Broken or worn pistons - Replace the pistons as required.

Drive System Troubleshooting

Drive system doesn't operate in one direction or either direction

Hydraulic oil level is low - Check and refill the hydraulic oil.
Defective or blocked track mechanism - Correct blockage or repair tracks.
Relief valve is stuck - Repair or replace.
Dirty hydraulic filter or suction line - Change hydraulic filter or service suction line.
Defective or worn foot or hand controls - Change or repair.
Worn drive motor or pump - Inspect and change as required.

Machine will not drive straight or drives jerky

Damaged or jammed undercarriage tracks - Remove jamming or repair tracks.
Tracks are sagging or malfunctioning - Correct track sag with tensioning or repair tracks.
Undercarriage track frame is clogged with dirt, debris, or foreign objects - Clean track frame, remove debris and foreign objects.

Reduced power

Hydraulic oil filter is plugged - Change hydraulic filter.
Damaged or opened relief valve - Replace or close relief valve.
Transmission components are damaged or faulty - Inspect and replace defective parts.
Worn input drive shaft - Replace drive shaft.
Air in hydraulic system - Need to bleed air.

Drive system overheating

Insufficient hydraulic oil - Need to add oil.
Hydraulic fluid filter is clogged - Change or service hydraulic filter.
Worn or defective relief valve - Repair or replace.
Drive pump or hydraulic motor is damaged - Repair or replace faulty component.
Plugged hydraulic oil cooler - Cooling fins should be cleaned.
Overloaded drive system - Reduce drive system load.

Excessive noise

Incorrect oil viscosity - Use oil of proper viscosity.
There is air in the hydraulic system - Need to bleed air.
Hydraulic motor or drive pump is worn - Change or repair faulty component.
Worn or defective mechanical parts of drive system - Check the parts for defect or damage and change if required.

Hydraulics Troubleshooting

Hydraulic system overheats

Hydraulic pressure is not adjusted correctly - Set pressure correctly.
Main relief valve is faulty or misadjusted - Replace or set up the relief valve.
Contaminated hydraulic oil - Hydraulic oil change required.
Lack of hydraulic fluid - Need to add fluid.
Hydraulic pump is defective - Install new pump or repair it.

Boom can't lift or drop

Defective lift controls - Inspect and repair if necessary.
Damaged hydraulic oil pump - Replace or repair pump if necessary.
Defective hydraulic control valve - Repair or replace hydraulic valve.
Hydraulic cylinder failure - Repair or replace hydraulic cylinder.
Hydraulic fluid level low - Fill the system to proper hydraulic fluid level.

Bucket does not tilt

Bucket tilt controls are defective - Repair or change.
Defective hydraulic pump - Repair or replace pump if necessary.
Faulty hydraulic control valve - Repair or change the valve.
Bucket cylinder is faulty - Repair or install a new cylinder.
Hydraulic oil level low - Need to add oil.

Slow bucket or lift arm operation

Faulty hydraulic oil pump - Check pump flow and install new pump if necessary.
Leaking hydraulic cylinder - Correct leakage by changing the seals.
Insufficient hydraulic oil - Fill the system to proper hydraulic oil level.
Faulty or incorrect setting hydraulic control valve - Adjust properly or repair.
Hydraulic pressure loss - Hydraulic pressure must be set correctly.

Lift arm or bucket jerks when working

Air in hydraulic system - Bleed air from hydraulic system.
Dirty hydraulic oil filter element - Replace or clean the filter.
Dirty hydraulic oil - Fill up with fresh hydraulic oil.
Scored cylinder tube or rod - Change damaged component.

Hydraulic pump is excessively noisy

Lack of oil or hydraulic leakage - Correct hydraulic leaks or top up oil as needed.
Hydraulic filter clogging - Replace or clean the filter.
Suction line clogging - Suction line needs to be cleaned.
Air trapped in hydraulic pump - Air bleeding is required.
Worn pump components - Rebuild or change hydraulic pump.

Electrical Troubleshooting

Battery is not charging

Loose or corroded electrical wiring connections - Tighten or service cable connections.
Battery terminal connectors are faulty - Change terminal connectors.
Battery dead cell - Battery replacement required.
Loose or damaged belt - Adjust belt tension or replace belt.

Starter cranks slow

Low battery output - Charge the battery.
Battery will not hold charge - Service charging system or install new battery.
Disconnected battery cables or bad terminals - Connect wiring correctly or install new terminals.

Starter will not crank

Battery is discharged or defective - Replace or charge as required.
Wiring is incorrectly connected or disconnected - Inspect wiring and connect correctly.
Battery capacity is low - Recharge the battery.
Damaged starter motor - Starter needs to be replaced.