Water in engine oil

[38plymouth]

I have a 120 mercruiser I/O, I think it's a 1979. After several months of use I find alot of water in the oil. I would guess 1-3 quarts of water. The engine runs great and the sparkplugs look really good. I'm going to tear the engine down to look for a cracked head or block. My problem is that since it runs so good I'm wondering if it could be something simple. I was told there is a baffle of some sort in the exhaust manifold that prevents water from coming into the engine. I do have a rattle noise in the rear area that sounds like it's sheet metal or tin when it rattles. Is there anything thing else that I should look for before pulling the head? Is it possible it could be something more simple than a crack or a head gasket.

 

[snapperbait]

Re: Water in engine oil

Yup.. Could be that the exhaust manifold is rusted out on the inside... Don't know about any baffles but there may be... <br /><br />Thats the first place to look...

 

[flashback]

Re: Water in engine oil

could be gasket related also. you know, head gasket, intake gasket, etc. .......good luck....

 

[Trent]

Re: Water in engine oil

Stop!<br /><br />Dont pull your head. Most times water in the engine is riser or manafold. Remove and have them pressure checked. But with a engine that old I would just replace. If you got this long your running in freshwater! The tapping your hearing is the "exhaust shutter" you were talking about. It keeps water from comming inside the exhaust on a sudden stop or waves comming onto the stearn of the boat. I would replace the riser, manafold and gaskets. VERY COMMON.