Section 12: Troubleshooting
4220ST & 4420ST Light Utility Vehicles 700-504M
8/05/08
48
Table of Contents
Engine loses power
Throttle cable is sticking.
Clean and oil throttle cable. Replace
worn or damaged cable.
Choke cable is sticking.
Clean and oil choke cable. Replace
worn or damaged cable.
Spark plugs are defective.
Replace spark plugs.
Spark plugs are fouled.
Clean spark plugs or replace.
Fuel supply is restricted.
Check for dirt in fuel tank.
Fuel line is plugged, pinched, or kinked.
Clean or replace fuel line.
Fuel leaks into the crankcase.
Clean or replace fouled spark plugs.
Verify choke position is not stuck on.
Engine oil level is high.
Drain excess oil, check for gas in the
oil. Change if gas is present.
Fuel octane is incorrect.
Use unleaded 87 minimum octane.
Throttle cable is faulty or out of
adjustment.
Adjust or replace throttle cable.
Air cleaning element is plugged.
Replace or clean air cleaner with air.
Engine is overheating.
See Symptoms for engine
overheating.
Engine runs unevenly
Electrical connections are loose.
Reattach electrical connections.
Engine cooling fins are plugged.
Allow engine to cool. Clean cooling
fins with high pressure air.
Throttle cable is sticking.
Clean and oil throttle cable. Replace
worn or damaged cable.
Choke cable is sticking.
Clean and oil choke cable. Replace
worn or damaged cable.
Fuel is stale or dirty.
Replace fuel with new fuel.
Fuel line is plugged.
Clean fuel line.
Fuel type is incorrect.
Use unleaded 87 minimum octane.
(Methanol not allowed).
Fuel leaks into the crankcase.
Clean or replace fouled spark plugs.
Verify choke position is not stuck on.
Spark Plug wiring is defective.
Replace spark plug wiring.
Spark plug is defective.
Replace spark plugs.
Spark plug is fouled.
Clean spark plugs or replace.
Carburetor is not adjusted correctly.
Adjust carburetor.
Air cleaner is plugged.
Replace air cleaner.
Engine starts in gear
Neutral switch is adjusted incorrectly.
Adjust neutral switch to be engaged
with shift selector in neutral.
Shifter link is out of adjustment.
With shift selector in neutral, adjust
shifter link at engine to be in neutral
position.
Symptoms
Probable Causes
Suggested Remedies
