Closed cooling

[Buttanic]

I have a 1975 pre Alfa 120 Mercruiser that I would like to convert to closed cooling. I have noticed on 120's and 140's with factory closed cooling the exhaust manifold is not fresh water cooled only the engine. Why is the manifold not fresh water cooled like most of the other Mercruisers. Is it because the heat exchanger does not have the capacity to cool both the engine and the manifold. If so could it be done with a larger heat exchanger. <br /><br />Buttanic

 

[Bondo]

Re: Closed cooling

Freebe Tony is building Just such a System Now........<br />Do a search for Tony's Posts over the last month or so..... He's even posted Pictures......<br />He's doing the 165hp, but your motor is the Same, just 2 cylinders Shorter......