"Besides costing a lot more, m
"Besides costing a lot more, marine starters (as well as alternators, distributors, etc.) are made for marine applications.
More specifically they are spark protected and the windings and magnets are supposedly sealed and protected for use in a humid damp environment.
If you use an auto starter, or any other non-marine electrical component, you run the risk of an explosion if gasoline vapors are in the bilge (gasoline vapors are heavier than air). This would definitely spoil your day, and that of anyone else who might be in the boat with you at the time.
Another concern is that if your boat blows up and the insurance company finds any evidence of non-marine components, they can refuse to pay out.
In the end though, it's your call.
Personally I would not take the chance.
Rod"