Harbor Freight Tools 68122 User Manual page 16

Problem
Engine misfires 1. Spark plug cap loose.
2. Incorrect spark plug gap or
3. Defective spark plug cap.
4. Old or low quality gasoline.
5. Incorrect compression.
Engine stops 1. Low oil shutdown.
suddenly
2. Fuel tank empty or full of impure
3. Defective fuel tank cap creating
4. Faulty magneto.
5. Disconnected or improperly
Engine stops when 1. Dirty air filter
under heavy load
2. Engine running cold.
Engine knocks 1. Old or low quality gasoline.
2. Engine overloaded.
3. Incorrect spark timing, deposit
Engine backfires 1. Impure or low quality gasoline.
2. Engine too cold.
3. Intake valve stuck or overheated engine.
4. Incorrect timing.
Follow all safety precautions whenever diagnosing or servicing the equipment or engine.
Page 16
Possible Causes
damaged spark plug.
or low quality gasoline.
vacuum, preventing proper fuel flow.
connected spark plug cap.
buildup, worn engine, or other
mechanical problems.
For technical questions, please call 1-800-520-0882.
Probable Solutions
1. Check wire connections.
2. Re-gap or replace spark plug.
3. Replace spark plug cap.
4. Use only fresh 87+ octane unleaded gasoline.
5. Diagnose and repair compression.
(Use Engine will not start:
COMPRESSION RELATED section.)
1. Fill engine oil to proper level. Check
engine oil before EVERY use.
2. Fill fuel tank with fresh 87+
octane unleaded gasoline.
3. Test/replace fuel tank cap.
4. Have qualified technician service magneto.
5. Secure spark plug cap.
1. Clean or replace element.
2. Allow engine to warm up prior
to operating equipment.
1. Fill fuel tank with fresh 87+
octane unleaded gasoline.
2. Do not exceed equipment's load rating.
3. Have qualified technician diagnose
and service engine.
1. Fill fuel tank with fresh 87+
octane unleaded gasoline.
2. Use cold weather fuel and oil
additives to prevent backfiring.
3. Have qualified technician diagnose
and service engine.
4. Check engine timing.
Vertical Engine