boat was submerged

[REDSOXS1]

i have an inboard out board 145 hp mercruiser engine that was completely submerged i need to know how to get it running again. also im replacing the deck. its a fibergass wellcraft/bow rider 17 ft im wondering if the hull will lose structual integrity where the deck meets the hull after i replace it and fiberglass over it.

[Thunderhead19]

Salt water immersion or fresh water immersion?

[REDSOXS1]

fresh water. thanks for your help

[Tim B]

First job is to check if the prop-shaft still turns, check the transmittion, take out the plugs and check that the pistons still slide etc.

Then check the cooling water jackets, if everything turns and flows, drain the engine of oil, re-fill it and turn it a few more times by hand (with plugs out; check it sounds ok) then turn it over on the starter motor.

Once you're happy that it looks and sounds alright put the plugs in and try it again. If it's still ok, check the fuel and oil pump, shut-off valve etc. and connect the fuel feed (with a valve in the fuel line!!) and turn it over. When you get it to start, you've done it.

Depending whether it's petrol or diesel and how long it's been submerged this may be quite a long job. I would suggest removing the engine first and bolting it to a steel framework so you can get at all of it. Also, if the worst happens It won't take the boat with it.

Once it is running you'd be well advised to run the engine under diferent loads and take some readings to test it. You can then plot RPM/Power RPM/Efficiency and see how well it matches the plublished data.