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For engine technical questions, please call 1-800-520-0882.
For other technical questions, please call 1-800-444-3353.
Item 69086
Problem
Possible Causes
Probable Solutions
Engine misfires
1. Spark plug cap loose.
2. Incorrect spark plug gap or
damaged spark plug.
3. Defective spark plug cap.
4. Old or low quality gasoline.
5. Incorrect compression.
1. Check wire connections.
2. Re‑gap or replace spark plug.
3. Replace spark plug cap.
4. Use only fresh 87+ octane
unleaded gasoline.
Do not use gasoline with more than
10% ethanol (E15, E20, E85, etc.).
5. Diagnose and repair compression.
(Use
Engine will not start:
COMPRESSION RELATED
section.)
Engine stops
suddenly
1. Low oil shutdown.
2. Fuel tank empty or full of impure or low
quality gasoline.
3. Defective fuel tank cap creating
vacuum, preventing proper fuel flow.
4. Faulty magneto.
5. Disconnected or improperly
connected spark plug cap.
1. Fill engine oil to proper level. Check
engine oil before EVERY use.
2. Fill fuel tank with fresh 87+ octane
unleaded gasoline.
Do not use gasoline with more than
10% ethanol (E15, E20, E85, etc.).
3. Test/replace fuel tank cap.
4. Have qualified technician service magneto.
5. Secure spark plug cap.
Engine knocks
1. Old or low quality gasoline.
2. Engine overloaded.
3. Incorrect spark timing, deposit
buildup, worn engine, or other
mechanical problems.
1. Fill fuel tank with fresh 87+ octane
unleaded gasoline.
Do not use gasoline with more than
10% ethanol (E15, E20, E85, etc.).
2. Do not exceed equipment’s load rating.
3. Have qualified technician
diagnose and service engine.
Engine backfires
1. Impure or low quality gasoline.
2. Engine too cold.
3. Intake valve stuck or overheated engine.
4. Incorrect timing.
1. Fill fuel tank with fresh 87+ octane
unleaded gasoline.
Do not use gasoline with more than
10% ethanol (E15, E20, E85, etc.).
2. Use cold weather fuel and oil
additives to prevent backfiring.
3. Have qualified technician
diagnose and service engine.
4. Check engine timing.
Equipment does
not operate with
engine running
1. Engine idling.
2. Broken or loose belt.
1. This is normal operation.
Increase engine speed to start operation.
2. Inspect belt and replace if broken or worn.
Tension belt properly.
Follow all safety precautions whenever diagnosing or servicing the equipment or engine.
SAFETY
OPERA
TION
MAINTENANCE
SETUP