Hot water inst. in fresh water cooled eng

this was just talked about on planetnautique as well. my response is to start researching heat exchangers and start fabricating. I am sure you could come up with something. Would you want your shower to spray the same water coming out of the lake? If not, you could install a watertank in the boat and fill it up before you leave home. what kind of boat, are you in salt water?

I have a correct craft 1996, but i am going to install a heat exchanger because of there is salt water where i live.

your idea with a water tank could be used , but then you will need another heat exchanger for this 8i am lucky ,I have a little one in spare, so maybe I should try that. In the water tank there should be a little pump to circulate the water and another one (?) for the shower. There could be some problems with the water tenperature (?) the water in the tank could reach motor temperature 85° Celsius....

yes, you are right... if you had a freshwater holding tank, you would have to make sure the temp doesnt get too hot. I dont know what to do about that. On the other hand, you could leave the water in the tank as cold water and let it heat-on-demand when you pump it. Make the heat exchanger after the watertank. I do not know how much heat cold water could pick up passing through a heat exchanger only once.   Just a thought.