MD7A Fresh Water cooled engine - water flow diagram

[ckreitlein]

I am preparing an MD7A engine w/ heat exchanger for installation in my CD30 to replace the rusted raw water-cooled MD7A currently in the boat. I took all the hoses off the MD7A replacement engine and now am not sure if I have them back on correctly. Does anyone have a schematic of the water flow in an MD7A engine w/ heat exchanger? I would appreciate seeing one.

[Maine_Buzzard]

From the online document I once found from Martec some time ago.

The freshwater loop goes out from an electric pump to the copper pipe that feeds the exhaust log and the bottom of the thermostat housing. Coming out of the thermostat housing, the freshwater goes to the heat exchanger, then to the pressure tank (the high point in the system).
It then goes to the inlet of the electric pump.

Raw water- from the seacock and strainer, to the raw water pump inlet. From the pump, to the other half of the heat exchangern(with a zinc).
Out of the exchanger, to a vacuum breaker, then to the exhaust injector.

http://www.ybw.com/forums/showthread.ph ... ctric-pump

Hope this helps.

[ckreitlein]

That answers it... thanks