Water in oil, where to start

[superiormgmt]

I was about to tear into my Mercruser 350 atempting to change my head gaskets. I read on this site that it could be Exhaust manifolds / Risers. This boat has been sitting, outside, for the last five years but only has 160 hours on the 1984 motor. It ran fine before it sat. I pulled off one riser and rusty water poured out of the two center outlets. Does this call for a Presure check, or is there any way to tell if it is just the Exhaust risers? Thanks for any help

 

[rodbolt]

Re: Water in oil, where to start

5 years outside ? was it winterized properly? you may just have a busted block as well. I would pressure test the block assy before dissasembling anything. if the risers and manifolds are originals they are about over it. if the block is not cracked replace the manifolds and risers.

 

[superiormgmt]

Re: Water in oil, where to start

The plugs were pulled and water drained before it sat.

 

[superiormgmt]

Re: Water in oil, where to start

There was about 3 quarts of water in the oil the first time I drained it after sitting.