Connecting raw water cooling to water heater
My new (30 year old) sailboat has a 1982 2GM (raw water cooled), that was previously hooked up to a Rartitan water heater - that went bad, and was disconnected. I recently removed the Raritan, and am considering replacing it with a Force 10 (as they are half the price). The previous owner had disconnected the faulty old heater, and put the engine hoses back to original, so I am not sure where to come off the engine raw water cooling. I follow the raw water, from seacock to raw water pump, into the engine, but then there is a short hose, that connects to the engine again, and then the hose going to the water exhaust pipe. Just want to make sue this is feasible, and any help on the best way to do it would be appreciated.
The boat was in salt water, during the engines 25 year life, but will now be in fresh water 95% of the time. I realize that I could add a fresh water kit, but as the boat will be in fresh water anyway, I would like to avoid that expense (as presumably one of the biggest benefits would be to avoid salt water to the engine)
I would like to hear form anyone who has experience using a raw water system to heat the hot water, or can tell me how much efficiency difference there would be this way.