Engine
Starter motor does not operate or does not turn engine over
1. Engine run switch in off position.
2. Ignition switch not on.
3. Discharged battery , loose or corroded connections (solenoid chatters).
4. Start control circuit, relay or solenoid damaged.
5. Electric starter shaft pinion gear not engaging.
Engine turns over but does not start
1. Fuel tank empty.
2. Fuel supply valve turned off.
3. Fuel supply valve or filter clogged.
4. Discharged battery, loose or corroded connections.
5. Fouled spark plugs.
6. Spark plug cables in bad condition or cable connections loose.
7. Ignition timing badly out of adjustment.
8. Loose wire connection at coil, battery connection or at plug between ignition module and sensor.
9. Damaged ignition coil.
10. Damaged ignition module or sensor.
11. Sticking or damaged valve or tappets too tight.
12. Engine oil or transmission lubricant too heavy (winter operation)