Bobcat T750 Track Loader Troubleshooting

The Bobcat T750 compact track loader is powered by Kubota V3800 diesel engine with a rated power of 85 hp (63 kW) or Bobcat D34 diesel engine with a rated power of 85 hp (63 kW). The Bobcat T750 is equipped with 1-speed or 2-speed hydrostatic transmission, vertical-lift loader boom, solid-mounted undercarriage with 5 triple flange rollers, and rubber tracks. The hydraulic system has a pump with fluid flow rate of 23 gpm (87.1 lpm). The hydraulic pressure is 3550 psi (245 bar). The loader has a rated operating capacity of 3325 lbs (1508 kg) and tipping load of 9500 lbs (4310 kg). The lift height is 132" (3350 mm) to hinge pin, and dump height is 104.3" (2650 mm).

Engine Troubleshooting

Engine hard to start or doesn't start

Air in fuel system - Bleed fuel system.
Dirty fuel filter - Clean the filter or install new filter element.
Clogged or burnt injection nozzle - Replace injection nozzles.
Water or dirt in fuel system - Drain, flush, and service the system.
Excessive valve clearance - Adjustment procedure required.
Damaged fuel injection pump - Replace injection pump or repair it.

Engine stalls after starting

Air cleaner is dirty - Service or replace air cleaner.
Clogged fuel filter - Install new filter element.
Poor fuel injection pump tightness - Look for any leaks of fuel pump, tighten it fast.
Fuel injectors are faulty or clogged - Clean fuel injectors or change it.
Fuel injection pump is broken - Change or repair the pump.

Engine shuts off suddenly while running

Coolant temperature is low - Normalize the temperature by warming up the engine.
Dirty fuel filter - Clean the filter or install new filter element.
Air in fuel tank - Bleed fuel tank.
Faulty fuel injection nozzles - Clean or change injection nozzles.
Fuel injection pump timing is not adjusted - Set up as recommended.

Engine stalls when idling

Wrong adjustment of low idle speed - Adjust low idling as recommended.
Fuel injection pump damage - Change or repair the pump.
Clogged or defective injectors - Test and replace fuel injectors if necessary.
Valve clearance is out of adjustment - Correct valve clearance.

Loss of engine power

Plugged air filter - Clean or change filter.
Clogged injection nozzle - Install a new kit of correctly balanced nozzles.
Insufficient fuel injection pressure - Test fuel injection pressure and adjust it correctly.
Valve clearance is not correct - Adjustment procedure required.
Wrong adjustment of low idle speed - Adjust low idle speed.
Dirty fuel lines or hoses - Clean fuel system hoses and lines.
Damaged cylinder-head gasket - Install a new gasket.
Piston rings are worn or damaged - Piston rings need to be replaced.

Engine overheated

Engine coolant is insufficient - Top up coolant fluid and check system for leaks.
Insufficient engine oil - Fill up the engine oil.
Radiator fins are clogged or radiator cap is faulty - Install new cap or clean radiator.
Fan belt is loose or defective - The fan belt needs to be replaced.
Diesel engine is overloaded - Load reducing is recommended.

Insufficient oil pressure

Engine oil insufficient - Check oil level and add oil as required.
Oil filter is dirty - Replace or service engine oil filter.
Oil grade or viscosity is wrong - Use correct viscosity oil.
Incorrect crankshaft bearing oil clearance - Change bearings.
Worn oil pump - Repair or replace.

Engine noise or knocking

Engine oil level low - Check and refill engine oil.
Engine not warmed up - Warm up engine as required.
Incorrect adjustment of fuel injection pump timing - Adjust as recommended.
Incorrectly set low idle speed - Correct the settings.
Clogged or defective injectors - Test and replace fuel injectors if necessary.
Misaligned or defective connecting rod - Need to align or replace the connecting rod.
Pistons are worn or broken - Pistons need to be replaced.

Drive System Troubleshooting

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

Low hydraulic oil level - Need to add oil.
Track mechanism is damaged or blocked - Remove blockage or repair tracks.
Stuck relief valve - Service or change relief valve.
Plugged suction line or hydraulic filter - Replace hydraulic filter or clean suction line.
Defective foot or hand controls - Change or repair.
Drive pump or motor malfunction - Inspect and replace as necessary.

Machine does not move straight or moves jerky

Damaged or jammed track mechanism - Repair or remedy jamming.
Faulty or loose tracks - Adjust track tension or replace tracks.
Track frame is clogged with debris, dirt, or foreign objects - Clean track frame, remove debris and foreign objects.

Power is too low

Hydraulic oil filter is clogged - Change hydraulic filter.
Relief valve is opened or defective - Close or replace relief valve.
Transmission parts are faulty or damaged - Check and change defective components.
Stuck input drive shaft - Repair or replace faulty drive shaft.
There is air in the hydraulic system - Bleed air from hydraulic system.

Drive system keeps overheating

Low hydraulic oil level - Checking hydraulic oil level and add if necessary.
Hydraulic fluid filter is dirty - Replace hydraulic filter.
Relief valve defective or worn - Change or repair defective relief valve.
Worn hydraulic motor or drive pump - Check and repair if required.
Hydraulic oil cooler is dirty - Cooling fins need to be cleaned.
Drive system is overloaded - Load needs to be reduced.

Drive system is noisy

Oil viscosity is wrong - Use correct oil viscosity.
There is air in the hydraulic system - Bleed air from hydraulic system.
Drive pump or hydraulic motor is damaged - Repair or replace faulty component.
Worn or defective mechanical parts of drive system - Check drive system and change faulty components.

Hydraulics Troubleshooting

Hydraulic system has overheating

Hydraulic pressure is incorrect - Adjust pressure correctly.
Main relief valve is damaged or adjusted improperly - Adjust or replace the relief valve.
Contaminated hydraulic oil - Change hydraulic oil.
Hydraulic fluid level is insufficient - Need to add fluid.
Faulty hydraulic oil pump - Install new pump or repair it.

Lift arm fails to drop or lift

Lift controls are defective - Repair or change.
Defective hydraulic pump - Install new pump or repair it.
Hydraulic control valve malfunction - Replace or repair the valve.
Defective hydraulic cylinder - Repair or replace hydraulic cylinder.
Low hydraulic fluid level - Add fluid as required.

Bucket does not function

Damaged bucket controls - Inspect and repair if necessary.
Hydraulic pump is broken - Change or repair hydraulic pump if required.
Hydraulic control valve is faulty - Change or repair hydraulic valve.
Broken bucket cylinder - Repair or change cylinder.
Hydraulic fluid level low - Checking hydraulic fluid level and add if necessary.

Bucket or lift arm moves slowly

Defective hydraulic pump - Test the pump performance and change pump if required.
Leaking hydraulic cylinder - Change cylinder piston seals.
Insufficient hydraulic oil - Need to add oil.
Defective or not adjusted hydraulic control valve - Adjust correctly or repair.
Low hydraulic pressure - Hydraulic pressure must be set correctly.

Bucket or boom is working jerkily

Hydraulic system is leaking air - Bleed air from system.
Clogged hydraulic oil filter element - Change or clean oil filter.
Hydraulic fluid contamination - Change hydraulic fluid.
Scored cylinder tube or rod - Replace failed component.

Excessive hydraulic pump noise

Low oil level or hydraulic leaks - Remedy hydraulic leakage or refill oil as necessary.
Dirty hydraulic filter - Clean or change the filter.
Dirty suction line - Suction line needs to be cleaned.
Air enters the pump - Need to bleed air.
Pump parts are worn out - Install new hydraulic pump or rebuild it.

Electrical Troubleshooting

Battery is not charging

Wiring connections are loose or corroded - Tighten or clean electrical wiring connections.
Faulty electrical terminal connectors - Terminal connectors need to be changed.
Battery dead cell - Change the battery.
Damaged or loose belt - Adjust belt tension or replace belt.

Starter motor cranks slow

Low battery power - Charge the battery.
Battery does not hold charge - Service battery or change it.
Wires are disconnected or battery terminals are corroded - Check battery wires and service or replace terminals.

Starter will not work

Battery is drained or defective - Recharge or replace battery.
Wiring is improperly connected or disconnected - Check wiring and connect properly.
Low battery output - Recharge the battery.
Starter motor is defective - Change or repair starter.