Home / Skid Steer Loaders / Bobcat Skid Steer Loaders / Bobcat M444

Bobcat M444 Troubleshooting

The Bobcat M444 skid steer loader is powered by 49.8 cu.in (0.8L) Onan Super CCK 4-cycle 2-cylinder air-cooled gasoline engine with a rated power of 15.5 hp (11.5 kW) at 3000 rpm. The Bobcat M444 is equipped with a radial-lift loader boom, variable sheave transmission, 60H drive chains, and 7.00x15 standard tires. The hydraulic system has a pump with fluid flow rate of 7.5 gpm (28.4 lpm). The hydraulic pressure is 1700 psi (117 bar). The skid steer loader has a rated operating capacity of 1000 lbs (454 kg) and tipping load of 2000 lbs (910 kg). The lift height is 108 inches (2745 mm) to hinge pin, and dump height is 86 inches (2185 mm).

Engine Troubleshooting

Engine difficult to start or doesn't start
Fuel tank is empty - Add fuel.
Wrong fuel grade - Use quality fuel.
Air in fuel tank - Bleed fuel tank.
Disconnected or loose spark plug wire - Check spark plug wiring connection, repair or change.
Defective spark plug - Install new spark plug.
Dirty fuel filter - Fuel filter needs to be replaced.
Brake pedal not depressed - Press the brake pedal.
Carburetor settings incorrect - Adjusting as required.
Poor cylinder compression - Check cylinder block and change worn parts.
Damaged or incorrectly adjusted choke cable - Adjust properly or replace the cable.

Engine runs intermittently
Air intake grill is clogged - Clean and wash as required.
Ignition system malfunction - Check ignition and replace faulty components.
Faulty or stuck choke cable - Service or change the cable.
Air filter element is plugged - Service or replace air filter.
Dirty or faulty fuel pump - Test fuel pump and replace if necessary.

Engine starts but then stalls
Spark plug is faulty - Change spark plug as required.
Carburetor is clogged or defective - Service or repair carburetor.
Ignition coil is faulty - Install a new ignition coil.
Loose or broken valve springs - Replace valve springs.
Stuck valves - Valves need to be cleaned.

Engine keeps overheating
Engine oil insufficient - Checking oil level and add if necessary.
Engine is running overloaded - Load reducing is recommended.
Clogged cooling fins - Need to clean or wash.
Carburetor fuel mixture is too lean - Make the correct settings.
Wrong ignition timing - Ignition timing needs to be set properly.
Valve setting is wrong - Valves needs to be set correctly.

Engine noise or knocking
Stale or low octane fuel - Change gasoline.
Engine is under excessive load - Reduce load.
Lack of engine oil - Checking oil level and add if necessary.
Low idle speed adjustment is incorrect - Adjust the low idle speed.
Dirty or defective fuel pump - Check fuel pump and replace if necessary.
Main bearings or crankshaft failure - Crankshaft or bearings need to be replaced.
Valve clearance is not correct - Need to adjust valve clearance.
Piston rings or cylinder bore are damaged - Change defective parts.

Engine loses power
Carburetor is clogged or incorrectly adjusted - Adjust carburetor properly or service it.
Air filter element is plugged - Change or service air filter.
Dirty or faulty fuel pump - Clean or change fuel pump.
Ignition system malfunction - Check ignition system and replace faulty parts.
Cylinder head gasket is defective - Change cylinder head gasket.
Stuck or burned valves - Service or change valves.
Worn or defective push rod - Push rod should be replaced.
Faulty cylinder block parts - Defective parts need to be replaced.
Plugged oil filter (if equipped) - Service or replace oil filter.

Excessive fuel consumption
Insufficient choke opening - Inspect choke cable and adjust as required.
Improper adjustment of carburetor main jet - Adjust main jet as required.
Spark plug is faulty or loose - Tighten or replace spark plug.
Stuck, burned, or worn valves - Replace or service valves.
Rings, sleeve, or piston are damaged - Replace defective components as required.
Improper valve clearance - Check and adjust.

High oil consumption
Seals or gaskets are wearing excessively - New components need to be installed.
Damaged valve stems or valve guides - Valves need to be changed.
Worn or stuck piston rings - Have piston rings replaced.
Piston or cylinder liner is scuffed - Inspect piston and liner, change as required.
Breather hose or pipe is plugged - Service or replace.

Drive System Troubleshooting

Machine will not move forward or backward
Insufficient hydraulic oil - Need to add oil.
Drive chain malfunction - Check drive chain and change defective parts.
Defective or worn relief valve - Repair or replace.
Dirty suction line or hydraulic filter - Service suction line or change hydraulic filter.
Worn or damaged foot or hand controls - Repair or change.

Power is too low
Plugged hydraulic oil filter - Change or clean hydraulic filter.
Transmission parts are damaged or faulty - Check and replace defective components.
Defective input drive shaft - Replace drive shaft.
Hydraulic system is leaking air - Bleed air from system.

Drive system keeps overheating
Low hydraulic fluid level - Add fluid as required.
Hydraulic fluid filter is plugged - Check, clean, or change as necessary.
Transmission parts are damaged or faulty - Check and repair if required.
Transmission overloading - Reduce the load.

Drive system is excessively noisy
Improper oil viscosity - Use correct oil viscosity.
Air leaks in hydraulic system - Air bleeding is required.
Transmission parts are worn - Check and repair if required.
Mechanical parts of drive system are worn or damaged - Check drive system and change faulty components.

Hydraulics Troubleshooting

Hydraulic system has overheating
Incorrect hydraulic pressure setting - Correct adjustment is required.
Unadjusted or defective main relief valve - Set up or change the relief valve.
Contaminated hydraulic oil - Hydraulic oil change required.
Lack of hydraulic fluid - Fill the hydraulic system with oil.
Worn hydraulic oil pump - Replace or repair pump if necessary.

Lift arm won't raise or lower
Damaged lift controls - Check and repair as required.
Damaged hydraulic oil pump - Repair or install new hydraulic pump.
Hydraulic control valve failure - Replace or repair the valve.
Faulty hydraulic cylinder - Install a new boom cylinder or repair it.
Insufficient hydraulic fluid - Checking hydraulic fluid level and add if necessary.

Bucket tilt does not work
Defective bucket controls - Check and repair as required.
Hydraulic pump failure - Replace or repair pump if necessary.
Hydraulic control valve malfunction - Repair or replace hydraulic valve.
Bucket cylinder failure - Repair or replace cylinder.
Low hydraulic fluid level - Add fluid as required.

Boom or bucket moves slowly
Hydraulic pump is faulty - Flow-rate hydraulic pump and replace pump if necessary.
Hydraulic cylinder oil leakage - Replace cylinder piston seals.
Low hydraulic oil level - Check and refill the hydraulic oil.
Hydraulic control valve is defective or set improper - Set correctly or repair.
Hydraulic system loosing pressure - Adjust it correctly.

Lift arm or bucket movements are jerky
Hydraulic system is leaking air - Bleed air from hydraulic system.
Hydraulic oil filter element is clogged - Clean or install new filter.
Dirty hydraulic oil - Hydraulic oil change required.
Cylinder rod or tube is scuffed - Replace defective component.

Hydraulic pump is excessively noisy
Insufficient oil level or leaking hydraulic system - Correct hydraulic leaks or top up oil as needed.
Hydraulic filter is clogged - Change or clean oil filter.
Suction line is dirty - Clean suction line as required.
Air enters the pump - Remove air from hydraulics.
Pump components are worn out - Rebuild or change hydraulic pump.

Electrical Troubleshooting

Battery is not charging
Wiring connections are loose or corroded - Tighten or clean connections.
Faulty battery terminal connectors - Terminal connectors need to be changed.
Battery failing - Replace the battery.
Damaged or loose belt - Adjust belt tension or replace belt.

Starter turns slow
Low battery output voltage - Battery is drained, recharge it.
Battery discharges quickly - Battery needs to be serviced or replaced.
Faulty battery terminals or disconnected cables - Check battery wires and service or replace terminals.

Starter doesn't crank
Battery is low or faulty - Battery needs to be recharged or replaced.
Battery cables are disconnected or improperly connected - Inspect cables and connect properly.
Low battery capacity - Low battery charging, charge as required.
Faulty starter motor - Repair or replace starter.