1983 Sea Ray with watery oil

[Stumpedboater]

After discovering water in the oil of my 5L Mercruiser, I drained the oil and filter. Next time out the starter drive broke and locked the starter. Changed the starter and went for a ride all to come back and find the oil was again contaminated. I believe the starter issue was because of water in the cylinders so I took out the plugs and the front three cylinders on the right bank all had water in them. The exhaust manifold was replaced before I got the boat earlier this year so it should be good but I am wondering so I took it off and have filled it with water to await a bleed down test. Is there a better way to test the manifold? I check the compression in all four cylinders in the right bank and they are between 150 and 160. Is it fair to assume the head and head gasket are good? If the bleed down doesn't prove anything what would be my next step? Any suggestions would be appreciated. Thanks

 

[bondo]

The exhaust manifold was replaced before I got the boat earlier this year so it should be good but I am wondering so I took it off and have filled it with water to await a bleed down test. Is there a better way to test the manifold?

Ayuh,..... Take the riser / elbow off, 'n inspect the gasket, as that's where they leak,....

 

[Stumpedboater]

Thanks for your insight. I have taken the manifold of and separated the riser as well. I did stand the manifold on end and filled it with water and overnight it probably leaked a cup of water into the exhaust portion of the manifold. Looks pretty conclusive that there is a hole in the inner chamber.