Failure of Engine to Start

We listed possible causes of the problem failure of engine to start:

1. Lack of fuel
2. Ignition switch off
3. Under‐priming or over‐priming
4. Incorrect throttle setting
5. Cold oil
6. Defective battery (battery ignition systems)
7. Dirty or defective spark plugs
8. Water in magneto
9. Wet ignition harness
10. Wrong grade of fuel
11. Spark advance retarded too far
12. Vapor in fuel system
13. Water in carburetor
14. Defective ignition wiring
15. Booster magneto defective
16. Incorrect valve and/or ignition timing
17. Defective magneto
18. Broken impulse coupling
19. Magneto breaker points defective
20. Incorrect valve clearance
21. Defective priming system
22. Internal trouble in carburetor
23. Intake manifold air leaks
24. Broken, shredded or defective camshaft
25. Internal engine failure
26. Spark plug wires crossed
27. Miscellaneous (turn engine over slowly by hand with the master & magneto switch off and note any unusual condition, particularly low compression.