Case 75XT Skid Steer Troubleshooting

The Case 75XT skid steer loader driveline system components: a 239 cu.in (3.9L) Case 4-390 four-cylinder direct injection liquid-cooled diesel engine with a rated power of 75 hp (55.9 kW) and single hydrostatic transmission. The hydraulic system has a pump with a rated capacity of 21 gal/min (79.4 l/min). The system relief pressure is 3000 psi (207 bar). The Case 75XT is equipped with a single reduction final drive, 100HS continuous roller chain, and 10x16.5 tires. The skid steer loader has a maximum lift height of 119.7" (3040 mm) to hinge pin and dump height of 90.6" (2300 mm). The rated operating capacity is 2200 lbs (998 kg), and tipping load is 4400 lbs (1996 kg).

Engine Troubleshooting

Engine difficult to start or doesn't start

Air in the fuel system - Air bleeding.
Fuel filter plugged - Clean or change the filter.
Fuel injection nozzles are dirty or defective - Change fuel injection nozzles.
Dirt or water in fuel system - Drain water or flush dirt from the system.
Excessive valve clearance - Check and adjust.
Fuel injection pump damage - Rebuild or replace pump.

Engine starts but stalls immediately

Clogged air filter - Change or service air filter element.
Fuel filter element is clogged - Replace the filter element.
Problems with fuel injection pump tightness - Inspect fuel injection pump for leaks.
Clogged or defective injectors - Replace fuel injectors.
Fuel injection pump is damaged - Repair or install new pump.

Engine stops unexpectedly during operation

Engine has not warmed up to recommended temperature - Warm up the engine.
Fuel filter element is dirty - Install new filter element.
Air in the fuel system - Air bleeding.
Dirty or damaged injection nozzles - Install a new kit of correctly balanced nozzles.
Fuel injection pump timing is not adjusted - Adjust fuel injection pump as required.

Engine stops at low idle speed

Incorrect low idle speed adjustment - Correct low idle settings.
Damaged fuel injection pump - Change pump or rebuild it.
Fuel injectors are dirty or defective - Replace or clean fuel injectors.
Excessive valve clearance - Correct valve clearance needs to be set.

Lack of engine power

Air cleaner is clogged - Clean or change cleaner.
Fuel injection nozzles are damaged - Service or change injection nozzles.
Uneven fuel injection pressure - Correct the pressure settings.
Excessive valve clearance - Have it adjusted.
Wrong adjustment of low idle speed - Adjust as required.
Fuel hoses or lines are dirty - Service fuel lines and hoses.
Cylinder head gasket is damaged - Change cylinder head gasket.
Leaking or damaged piston rings - Install new piston rings.

Engine overheating

Insufficient coolant - The cooling system needs to be refilled and checked for faults.
Not enough engine oil - Fill the crankcase with engine oil.
Clogged radiator core or leaking radiator cap - Install new cap or clean radiator.
Fan belt slipping or worn - Belt replacement is recommended.
Engine overloaded - Reduce engine load.

Oil pressure is low

Engine oil level low - Checking oil level and add if necessary.
Clogged oil filter - Change or clean engine oil filter element.
Incorrect oil viscosity - Use correct viscosity oil.
Excessive oil clearance of crankshaft bearing - Change bearings.
Worn oil pump - Repair or change.

Engine noise or knocking

Engine oil level low - Fill up the oil to required level.
Engine is not preheated - Warm up the engine as required.
Timing of fuel injection pump is incorrect - Set it up as required.
Too low idle RPM - Correct low idle adjustment.
Damaged or clogged injectors - Replace fuel injectors.
Connecting rod failure or misalignment - Need to replace or align the connecting rod.
Scored or worn pistons - Replace the pistons.

Drive System Troubleshooting

Drive system сan't work in either direction

Hydraulic oil is insufficient - Fill the system to proper hydraulic oil level.
Drive chain failure - Inspect drive chain and replace defective parts.
Defective input drive shaft - Rebuild or change.
Relief valve is damaged - Repair or replace.
Hydraulic filter or suction line is dirty - Check, clean, or change if necessary.
Worn or defective hand or foot controls - Change or repair.
Drive pump or motor is damaged - Repair or replace faulty component.

Reduced power

Hydraulic oil filter is dirty - Check, clean, or change as necessary.
Defective or open relief valve - Change or close relief valve.
Faulty or damaged transmission components - Check and change faulty components.
Damaged input drive shaft - Replace or service the drive shaft.
There is air in the hydraulic system - Need to bleed air.

Overheated drive system

Low hydraulic oil level - Fill the system to proper hydraulic oil level.
Hydraulic fluid filter is plugged - Check, clean, or change as necessary.
Relief valve failure - Service or change relief valve.
Hydraulic motor or drive pump failure - Change or repair faulty component.
Plugged hydraulic oil cooler - Clean the cooling fins.
Drive system overload - Load needs to be reduced.

Drive system is noisy

Improper oil viscosity - Use oil of correct viscosity.
Air in the hydraulic system - Bleed air from hydraulic system.
Hydraulic motor or drive pump failure - Repair or replace faulty component.
Worn or damaged mechanical parts of drive system - Check the components for defect or damage and change if necessary.

Hydraulics Troubleshooting

Hydraulic system overheated

Hydraulic pressure is not correct - Adjust pressure as required.
Main relief valve improper adjustment or failure - Adjust the valve or replace if necessary.
Dirty hydraulic fluid - Fill up with fresh hydraulic fluid.
Hydraulic fluid level is insufficient - Check and refill the hydraulic fluid.
Hydraulic pump is worn - Change or repair hydraulic pump if required.

Boom won't lower or raise

Lift controls are damaged - Repair or replace.
Damaged hydraulic oil pump - Repair or replace pump if necessary.
Hydraulic control valve malfunction - Change or repair hydraulic valve.
Hydraulic cylinder malfunction - Repair or install a new lift cylinder.
Insufficient hydraulic fluid - Fill up the hydraulic fluid.

Bucket tilt does not work

Bucket tilt controls malfunction - Change or repair.
Defective hydraulic pump - Repair or replace pump if necessary.
Damaged hydraulic control valve - Change or repair hydraulic valve.
Hydraulic bucket cylinder is broken - Change or repair cylinder.
Hydraulic oil level low - Checking hydraulic oil level and add if necessary.

Boom or bucket moves slowly

Worn hydraulic oil pump - Check pump flow and change pump if necessary.
Hydraulic cylinder oil leakage - Cylinder seals need to be replaced.
Hydraulic oil is insufficient - Checking hydraulic oil level and add if necessary.
Hydraulic control valve is not set properly or defective - Repair or adjust correctly.
Hydraulic pressure loss - Adjust pressure as required.

Lift arm or bucket jerks when working

Air trapped in hydraulic system - Bleed hydraulic system.
Hydraulic oil filter is dirty - Service or change the hydraulic filter.
Hydraulic oil is dirty - Fill up with fresh hydraulic oil.
Scratched cylinder rod or tube - Replace defective component.

Hydraulic pump is excessively noisy

Lack of oil or hydraulic leakage - Remedy hydraulic leakage or refill oil as necessary.
Hydraulic filter is clogged - Service or replace hydraulic filter.
Plugged suction line - Suction line must be serviced.
Pump is sucking air - Bleed air.
Pump components are worn out - Rebuild or replace hydraulic pump.

Electrical Troubleshooting

Battery won’t charge

Loose or corroded electrical wiring connections - Tighten or clean connections.
Battery terminal connectors are faulty - Terminal connectors need to be changed.
Battery is defective - Battery change required.
Belt is loose or defective - Adjust belt tension or replace belt.

Starter cranks slowly

Low battery output voltage - Low battery charging, charge as required.
Battery will not hold charge - Battery needs to be serviced or replaced.
Disconnected wiring or bad battery terminals - Connect wires correctly or change terminals.

Starter motor is not working

Battery is discharged or worn - Recharge or replace battery.
Battery wires are disconnected or incorrectly connected - Check wires and connect correctly.
Low battery voltage - Battery is drained, recharge it.
Starter motor failure - Starter should be changed.