Reward for lost Kraken!
Join Date: Apr 2006
Thanked 132 Times in 129 Posts
Rep Power: 11
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.