Join Date: Apr 2006
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Other than the corrosion? Raw water cooled engines use a low temperature thermostat in salt water, to prevent salt deposits from building up. Typically 140F. In fresh water, you want a hotter thermostat (170-180F) to get better performance from the engine.
If you can say "I really don't know" that's generally a good reason to hire a surveyor, because even a cheap boat can become a HUGE expense if there are problems you don't catch up front.