Oil Coming Out Of Exhaust!!!

Joined
Dec 6, 2011
Messages
13
Ok Here's the story...What is the possible problem(s)?.
Out on the water I ran at 3,700 RPM for about 5 minutes and took back down to 1,500 RPM and motor immediately died. Motor restarted under load (in gear) but ran extremely rough and died under 2000 RPMs' but lasted long enough to make the 20 minute trip back to the loading ramp. At the ramp I noticed oil coming out of the exhaust!!! Engine was not overheating.
Upon further inspection, the engine would tour over but not restart, the engine oil level was above the high mark which I assume means there was water getting into the engine. I have removed the oil but oil did not appear milky. I will compare to clean oil for further verification. I run in salt water and the boat is trailered and always flushed with fresh water after use. The engine on this boat was replaced in 2004 with a GM 350 Crate engine and I am not sure when the risers and manifolds were replaced. This is raw water cooled engine. The drive is Volvo Penta SP. The boat is a 1993 Wellcraft Excel 23.5.
I did a compression test. No water came out when spark plugs were removed, engine turns over, and had apx. 135 - 170 PSI compression on port Cylinders and 150-160 PSI compression on starboard cylinders. I removed port riser and exhaust manifold and noticed rust/scaling in raw water ports. I also noticed some sign if leakage at gasket between riser and manifold. I suspect it may be time to replace risers and exhaust manifolds. What are other tests and inspections I can do? Do these symptoms lead to a common hypothesis? What would cause oil to come out of exhaust...Am I over overthinking that could be more obvious????:facepalm:
 
Joined
Dec 6, 2011
Messages
13
Re: Oil Coming Out Of Exhaust!!!

I just read some more posts and came up with the idea that maybe it wasn't oil coming from exhaust. Maybe it was buildup of carbon being blown out exhaust from too much fuel in cylinders and restarting numerous times. Could too much water in oil cause engine to bog down like explained in prevous post? How much is too much?
 

tpenfield

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Staff member
Joined
Jul 18, 2011
Messages
18,149
Re: Oil Coming Out Of Exhaust!!!

There are a large number of possibilities, but I think that the extra level in the oil is tell tale of the problem. If you have rust in the exhaust ports of the manifold, then water is getting to them, and it may be coming through the engine.

One thing you could do is a pressure test of the cooling system within the engine. That may tell you if and where there is a leak.

I recently had an issue with my older engine and it turned out to be leaking around the area of the valve guides. It eventually got bad enough that it hydro-locked the engine. Bye-bye boat. :mad:
 

sqbtr

Senior Chief Petty Officer
Joined
Feb 23, 2010
Messages
716
Re: Oil Coming Out Of Exhaust!!!

With out knowing exactly what engine you have (electric fuel pump, mechanical fuel pump)

High oil level, doesn,t look milky and running rough. I would check the fuel pump, diaphragm may be blown sending raw fuel down carb throat and out the exhaust. Just a thought that the oil sheen may be fuel.
 
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