View Full Version : Water in engine oil cntd

10-19-2009, 01:31 PM
"Well, after I got the sludgy water infused oil out of the engine(see previous post), I put in new oil and filter. I performed a compression check on all 6 cylinders. The numbers I got are as follows- #1 cyl- 172psi, 3-174, 5-172, 2-178, 4-178, 6-181. I think the numbers looked good, but it didn't answer my problem on where the water was coming in! I now have the engine stripped down to the heads(removed intake manifold) and found a little more sludge in the valley between the heads, and a lot under the valve covers. I'm thinking about pulling the heads. I hope maybe there is a breach in the head gasket some where between the cylinders. Otherwise, I will be stumped about where the leak is. BTW, when draining the block, some sludge, instead of water, was slowly dripping out of the drain plug. My biggest fear is that my block has a crack in it, or it's rusted out in side where oil and water are mixing."

10-19-2009, 05:25 PM
"Your numbers look good, maybe a little bit high (probably due to some carbon build up) but nice and consistent.

The sludge indicates the interconnect between cooling and oil passages has been there a while.

If there was NO water in the cylinders when you pulled the pulls, the problem is likely due to one or two items. The first is the intake gasket leaking. Since you have removed it, it will be hard to confirm this as the source. the other likely cause is the crack you mentioned, in the intake, the heads, or the block.

Ideally, you could have pressure tested the cooling system before the intake came off. If the water jacket wouldn't hold pressure, you'd know that was the source for the water (but not exactly where). That said, you could take the intake and the heads to a machisne shop and get them to inspect those parts for cracks. If those aren't cracked, the block is about all that is left, sad to say.

How old is the block and does it have closed cooling?"

10-19-2009, 05:45 PM
"It's a 1999 block with outside raw water cooling. If it had a fresh water heat exchanger system then I would have checked it. I will pull the heads next then report what else I might discover. Thanks for replying,

03-16-2010, 01:51 PM
I have now pulled the engine(4.3 V6) and it's mounted on an engine stand. We pulled the heads and couldn't really see any evidence of where the water was invading the oil(breach). One thing of very importance is that we did look at the external sea pump and found that the impeller was shot! this explains why the engine suddenly overheated that day when I last ran the boat and I discovered I had a major problem with water in the oil. We suspect the manifold/risers to be the suspect area where there could have been a breach. Those parts are being replaced with new ones because they are getting pretty rusted out and the gasket flat areas between the risers and manifolds are being eaten away from years of use. With a flat block and some 200 grit we couldn't sand down the surface enough to make all of the areas flush (shiny). Therefore we suspect these parts to be the area where water would've breached in and pass through a valve. After we pulled the heads we noticed #5 exhaust valve had some rust color on it while the others were the normal black carbon color. the only thing left to do is clean up everything and reassemble with new gaskets and the new manifold sets. Hopefully the problem will be solved and no more water in the oil!