diesel in oil

[JusDreaming]

I checked the oil level and is higher rather than lower on dipstick. No sign of water in oil, so I suspect that it is fuel. It is not a lot higher level, but it is higher.
It is a perkins m-20/18 hp. I am currently in Marathon, and can make it on one engine to Ft.Lauderdale, but would rather not.
There is no smoke, and engine runs good, I am thinking it is an injector pump seal, but I am guessing!!!
Question is if Ineed that engine for an emergency, is it going to blow engine, and would it be better to send pump out for rebuild?

[model 10]

Does this engine have a lift pump? I would guess it is more likely to have a leaky diaphragm than the injection pump leaking into the engine.
I would change the oil if I were going to make a run for it.

[JusDreaming]

It does have a lift pump

[rw58ph]

The fuel pump seal probable broke/leaked which would allow fuel to be pump direct into the oil pan. Good thing you caught it as that is how engine run away as the engine start to feed it self and many times blow the engine. However the good side is your engine is sparkling clean like new.

[donradcliffe]

Two likely places where fuel can get into the oil are the lift pump diaphragm and the injection pump seals. See if you smell can diesel on the dipstick oil. The fuel in the oil will drop the oil pressure and can damage the bearings. If you want to go somewhere to get it fixed, I'd change the oil and reserve that engine for short term/emergency use.

[Vasco]

Most likely source lift pump diaphragm.

[donradcliffe]

Originally Posted by Vasco

Most likely source lift pump diaphragm.

Yanmar yes, Perkins no.

[Cheechako]

I've had this happen on Perkins and it was a fouled injector spraying a stream of diesel. This washed out the cylinder and went past the rings into the pan. It would make about 1-1.5 quarts in 8 hours.
If the level gets too high you could end up with a runaway engine. The same engine had a push rod that came off. long story. but that cylinder had low compression, but after correcting the injector the compression came up to normal after a couple hours running time. Engine ran fine the whole time.
As mentioned it could simply be the lift pump too.

[model 10]

Originally Posted by donradcliffe

Yanmar yes, Perkins no.

Why do you say that?

[uncledom]

Definitely can be a bad injector.

[GrowleyMonster]

Does the oil smell like diesel?

I say run it if you need to and check it often. If it definitely is making oil then don't run it, since you have two engines. Maybe crank it up just for docking if you NEED to, after an oil change, if it is a slow intrusion that doesn't raise the level noticeably in just a few minutes. But FIX IT IMMEDIATELY when possible. If you have a problem, it will probably get worse, and soon.

[JusDreaming]

assuming the mechanical lift pump was the problem, I installed an electric pump and completely bypassed the lift pump. But now the problem seems to be worse, so injector pump or bad injector?

[donradcliffe]

As engine runs well with no smoke (so its not an injector), and the lift pump isn't the problem (Yanmar lift pumps are more prone to failure than Perkins)--all signs point to a seal in the injector pump. Time to get the IP rebuilt.

[Terra Nova]

The "slightly" over-full oil sounds more like dip-stick/operator malfunction. If you can't see, feel or smell diesel in the oil, you might be imagining it.

[Cheechako]

Is there any oil sheen on the water from the exhaust? I had little smoke at all with my really bad injector, but was getting a pretty good oil sheen on the water.
If no oil on the water, then... yeah... bad news...