Caterpillar 259D3 Track Loader Troubleshooting

The Caterpillar 259D3 compact track loader is powered by 203.1 cu.in (3.3L) Cat C3.3B DIT 4-cylinder turbocharged diesel engine with a rated power of 73.2 hp (54.6 kW). The Caterpillar 259D3 is equipped with a 2-speed hydro transmission, vertical-lift loader boom, fully suspension undercarriage, and 12.6" (320 mm) or 15.7" (400 mm) rubber tracks. The hydraulic system has a pump with fluid flow rate of 20 gpm (76 lpm) or 30 gpm (112 lpm). The hydraulic pressure is 3335 psi (230 bar). The loader has a rated operating capacity of 2010 lbs (915 kg) and tipping load of 5740 lbs (2610 kg). The lift height is 121" (3.08 m) to hinge pin, and dump height is 89.9" (2.29 m).

Engine Troubleshooting

Engine starts hard or won't start

Air in the fuel pipes - Bleed the fuel pipes.
Dirty fuel filter - Change filter element.
Fuel injection nozzles are clogged or faulty - Clean or replace injection nozzles.
Dirt or water in fuel system - Drain water or flush dirt from the system.
Excessive valve clearance - Adjust valve clearance.
Faulty fuel injection pump - Install a new pump or rebuild.

Diesel starts but immediately shuts off

Air cleaner is clogged - Install new air cleaner element.
Fuel filter element is dirty - Change or clean the filter element.
Fuel injection pump is leaking - Repair any leaks.
Damaged or clogged injectors - Clean or replace fuel injectors.
Fuel injection pump is defective - Repair or change injection pump.

Engine stops suddenly during operation

Low coolant temperature - Warm up engine as required.
Fuel filter element is clogged - Clean the filter or install new filter element.
Air in the fuel pipes - Bleed the fuel pipes.
Fuel injection nozzles are damaged or dirty - If necessary, replace with a new nozzle.
Improper setting of fuel injection pump timing - Use the correct fuel injection pump timing adjustment.

Engine stalls while idle

Incorrectly adjusted low idle speed - Adjust the low idle speed.
Fuel injection pump is broken - Change pump or rebuild it.
Dirty or defective injectors - Replace fuel injectors.
Improper valve clearance - Adjust valve clearance according to specifications.

Lack of engine power

Clogged air filter - Clean or replace element.
Defective or clogged injection nozzle - If necessary, replace with a new nozzle.
Incorrect fuel injection pressure - Check the fuel injection pressure and adjust if necessary.
Valve clearance is not correct - Adjustment procedure required.
Incorrect low idle setting - Test and adjust.
Fuel hoses or lines are dirty - Clean fuel hoses and lines.
Cylinder head gasket is defective - Replace cylinder head gasket.
Piston rings are worn or damaged - Replace piston rings.

Engine overheating

Engine coolant is insufficient - The cooling system needs to be refilled and checked for faults.
Lack of engine oil - Check and refill engine oil.
Damaged radiator cap or dirty radiator core - Clean radiator or install new cap.
Fan belt slipping or worn - Replace the fan belt.
Diesel engine overloaded - Load reducing required.

Oil pressure too low

Engine oil insufficient - Checking oil level and add if necessary.
Plugged engine oil filter - Service or replace engine oil filter.
Improper type of engine oil - Use oil of proper viscosity.
Crankshaft bearing oil clearance is incorrect - Bearings need to be reinstalled.
Worn oil pump - Remove and inspect oil pump.

Abnormal engine noise or knocking

Insufficient engine oil - Checking oil level and add if necessary.
Engine is not warmed up to required temperature - Warm up the engine.
Improper fuel injection timing - Adjust the pump as required.
Low idle speed set incorrectly - Adjust as required.
Damaged or clogged injectors - Replace or clean fuel injectors.
Connecting rod is defective or not aligned - Align or change connecting rod.
Pistons are worn or scored - Pistons need to be replaced.

Drive System Troubleshooting

Machine is not moving forward or backward

Low hydraulic oil level - Need to add oil.
Blocked or defective undercarriage tracks - Repair or remedy blockage.
Stuck relief valve - Repair or install a new relief valve.
Dirty hydraulic filter or suction line - Change hydraulic filter or service suction line.
Defective foot or hand controls - Change or repair.
Defective drive pump or motor - Inspect and change as required.

Machine won't drive straight or drives jerkily

Undercarriage tracks are defective or jammed - Repair or fix jamming.
Tracks are worn or improperly tensioned - Adjust track tension or replace tracks.
Track frame is blocked with debris, dirt, or foreign objects - Remove debris or foreign objects and clean track frame.

Low power

Hydraulic oil filter is dirty - Check, clean, or replace as required.
Damaged or opened relief valve - Change or close relief valve.
Transmission components are faulty or damaged - Check and replace defective components.
Worn input drive shaft - Repair or install a new drive shaft.
Hydraulic system is leaking air - Need to bleed air.

Drive system is overheated

Hydraulic fluid is insufficient - Check and refill the hydraulic fluid.
Hydraulic fluid filter is plugged - Change or service hydraulic filter.
Relief valve is damaged - Rebuild or install a new relief valve.
Drive pump or hydraulic motor is damaged - Inspect and replace as necessary.
Plugged hydraulic oil cooler - Clean the cooling fins.
Overloaded drive system - Load needs to be reduced.

Drive system is excessively noisy

Oil viscosity is incorrect - Drain and refill with correct oil.
Air leaks in hydraulic system - Bleed air from system.
Defective drive pump or hydraulic motor - Inspect and replace as necessary.
Defective or worn mechanical components of drive system - Check the parts for worn or defect and replace if required.

Hydraulics Troubleshooting

Hydraulic system has overheating

Incorrect hydraulic pressure setting - Hydraulic pressure must be set correctly.
Faulty or improperly adjusted main relief valve - Adjust or change relief valve.
Contaminated hydraulic oil - The oil must be changed.
Not enough hydraulic fluid in the system - Add fluid to the hydraulic system.
Hydraulic pump is faulty - Replace or repair pump if necessary.

Boom fails to lift or drop

Lift controls are damaged - Inspect and repair if necessary.
Hydraulic pump is broken - Replace or repair pump if necessary.
Hydraulic control valve malfunction - Install a new valve or repair it.
Hydraulic cylinder is faulty - Install a new boom cylinder or repair it.
Insufficient hydraulic oil - Check and refill the hydraulic oil.

Bucket does not function

Damaged bucket controls - Replace or repair.
Hydraulic pump not working - Change or repair hydraulic pump if required.
Hydraulic control valve is faulty - Repair or replace the valve.
Damaged bucket cylinder - Install a new cylinder or repair it.
Low hydraulic fluid level - Fill up the hydraulic fluid.

Bucket or lift arm functions slowly

Faulty hydraulic oil pump - Check the pump capacity and replace pump if required.
Leaking hydraulic cylinder - Change cylinder piston seals.
Hydraulic oil is insufficient - Check and refill the hydraulic oil.
Hydraulic control valve is defective or set improper - Adjust properly or repair.
Hydraulic system loosing pressure - Adjust pressure correctly.

Bucket or boom is moving jerkily

Air in hydraulic system - Air bleeding is required.
Dirty hydraulic oil filter - Clean or replace the filter.
Hydraulic fluid is contaminated - The fluid must be changed.
Cylinder rod or tube is scratched - Change worn component.

Hydraulic pump makes excessive noise

Hydraulic leaks or low oil level - Remedy hydraulic leakage or refill oil as necessary.
Clogged hydraulic filter - Service or replace hydraulic filter.
Dirty suction line - Service the suction line.
Air trapped in hydraulic pump - Air bleeding is required.
Damaged pump parts - Rebuild or install new pump.

Electrical Troubleshooting

Battery will not charge

Electrical wire connections are corroded or loose - Tighten or clean connections.
Battery terminal clamps are defective - Replace terminal clamps.
Battery failing - Install a new battery.
Loose or defective belt - Belt needs to be adjusted or replaced.

Starter motor turns slow

Battery power is low - Recharge the battery.
Battery is draining quickly - Service or replace the battery.
Corroded battery terminals or disconnected wires - Connect wires properly or change terminals.

Starter motor won't turn

Battery is drained or defective - Charge or replace the battery.
Disconnected or incorrectly connected wires - Inspect battery wires and connect correctly.
Low battery voltage - Recharge the battery.
Starter motor is faulty - Change or repair starter.