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Oil splatter out of dip stick

August 16, 2017, 11:14:29 am

On one of my last days coming home I noticed some oil splatters coming out of the engine grill. There were a few others toward the rear coach engine room. I couldn't see any place that had a leak and the oil level was close to what I expected.
I did notice that the dip stick was loose and decided I must have not seated it properly.

We had the coach serviced in NAC and then home to Georgetown.

When we got home I again saw oil splatters in the front (belt side) of the engine and a few other backend places.
My diesel buddy says "crankcase vent". Unfortunately, he is in Maryland.

I'm parked in a gravel site, its 100+ in the Austin/Georgetown area for the foreseeable future, and we've been unpacking all week.

Any thoughts before I crawl under?
Thanks

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Re: Oil splatter out of dip stick

Reply #1 – August 16, 2017, 11:20:21 am

Elliott,

Not sure how the crankcase breather could do this unless it is obstructed, causing excessive crankcase pressure that is then forcing oil out.  Guess it wouldn't hurt to raise the bed and remove it and blow through it to verify it is not clogged.

Accessing through the bedroom will also allow you a better view of exactly where the oil is coming from.

And, if the crankcase was overfilled, oil would have come out the bottom of the crankcase breather hose, so down at the bottom of the engine.

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Re: Oil splatter out of dip stick

Reply #2 – August 16, 2017, 11:27:02 am

Is this a Cat?

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Re: Oil splatter out of dip stick

Reply #3 – August 16, 2017, 11:55:51 am

2 things,make sure the whole crankcase vent hose is clean,take off and clean so no oil/grease is inside.2nd,make sure the dip stick
is not vibrating out even a little,take some safety wire and wrap it so it cannot move out.If this is a Cummins engine the vent hose
is on top of the valve cover so in my opinion if you have a little too much oil this should not cause it to spill out more.Now if you have way too much oil I can see how that would cause a leak so check your oil level.

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Re: Oil splatter out of dip stick

Reply #4 – August 16, 2017, 12:25:54 pm

A fuel leak can look similar.

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Re: Oil splatter out of dip stick

Reply #5 – August 16, 2017, 02:02:38 pm

Quote from: gracerace – August 16, 2017, 11:27:02 am

Is this a Cat?

Cummins 8.3

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Re: Oil splatter out of dip stick

Reply #6 – August 16, 2017, 02:13:49 pm

Yes, a fuel leak can look much like oil. Did you recently change oil? Is the oil on the dipstick at the normal mark? If it's the dipstick, it could be excessive crankcase pressure from a clogged breather. If the oil level is higher on the dipstick, you could have a fuel leak from the lift pump into the crankcase. This will also dilute the oil and can cause engine damage if not fixed. Oil on the outside of the engine is something you want to find out about sooner than later. Check for fuel leaks at the lift pump.

Pierce

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