3.0 Mercruiser water in valve cover

[trevtt600]

I purchased a used 3.0 to replace mine with a cracked block (motor has a 30 day warranty). I ran it for the first time today out of the boat on the ground. After i ran for about 5 minutes or so, i shut it off, and removed the valve cover oil cap. I notice a water/oil milky mixture in the valve cover. I pulled the cover off because i am swapping it out with my old one, and there was a decent amount of milky substance in there. Is this something to be concerned about? Or since the motor probably has not been ran for over a year or more, is this just moisture that has been sitting in the motor for so long. Do i need to run it longer and see if my oil gets milky also? I installed my old manifold off old engine with a new gasket also. Pressure tested the manifold as per the instructions on this site with no leaks. What are your thoughts?

 

[grahamh]

Re: 3.0 Mercruiser water in valve cover

Something is wrong, I don't think that sitting alone would let that much moisture build up, unless maybe it was left outside in the rain without the oil cap on or something like that?

You could try draining the old contaminated oil, refilling it with new oil and running it again, just to make sure, but my guess is that something is wrong, either the new block is cracked too, or it could have a blown headgasket.

 

[fat fanny]

Re: 3.0 Mercruiser water in valve cover

Take it back (motor) not worth the hastle get another one!!!!!!