3GM30F Heat Exhanger

[heritage]

I have come to the conclusion that there are two varieties of tube assemblies that fit into the jacket of the 3GM30 heat exchanger. My heat exchanger has 52 small tubes, a horizontal rubber gasket separating the upper and lower section of tubes, and a large O-ring as the gasket. The tube assemble illustrated in the Yanmar parts dept. catalog and also the diagrams that I find on line, show a tube assemble with 25 larger tubes, two gaskets, one that has a "peace symbol" looking gasket that separates the upper and lower tubes.

My engine is the European made version, but the manuals say that the Japanese and European version have the same He, with the larger tubes.

My question is why does my engine have a different heat exchanger tube assembly. Is it original to the engine or an after-market replacement?

 

[Ted]

3GM30F Heat Exchanger

Can you post some photos of your heat exchanger? Take a look at the Yanmar identification tag mounted on the block. Does is show 3GM30 or 3GM30F. If there isn't a "F" is may be an aftermarket heat exchanger. The factory fresh water cooled version will always have an "F" but it still may be a Yanmar heat exchanger even though it wasn't delivered from the factory that way. A photo may tell the story.

 

[heritage]

Here are some pics. You can see in the first pic why I took the HE apart. Salt water leaking from the front cap. Needing to clean it up and replace the gasket.