Rear crank shaft seal

[Doe69936]

That does sound handy

[Doe69936]

Ok so having replaced the rear main seal I found that I had the same amount of oil leakage no so much from the bell housing but after cleaning up the oil to look for leaks I found its coming from my dipstick !.
So I'm getting too much crankcase pressure which also explains why I always seem to get too much smoke out of the breather tube.
However it does not blow oil out the breather tube which I find a little odd.
Anyways so thinking maybe too much oil in the crankcase I took out a gallon then another gallon .seem to improve some but still dribling oil out the dipstick
So I loosened the oil fill cap and let it sit there and sure enough it's bouncing all over the place so I'm assuming I'm in for some major engine work
But I've read a little about some possible turbo or air compressor issues causing the same problems.
Thing is the motor starts easy runs cool and gets good milage which to my mind is not indicative of that kind of cylinder blow By

[Seriousracer]

Originally Posted by Doe69936

Ok so having replaced the rear main seal I found that I had the same amount of oil leakage no so much from the bell housing but after cleaning up the oil to look for leaks I found its coming from my dipstick !.
So I'm getting too much crankcase pressure which also explains why I always seem to get too much smoke out of the breather tube.
However it does not blow oil out the breather tube which I find a little odd.
Anyways so thinking maybe too much oil in the crankcase I took out a gallon then another gallon .seem to improve some but still dribling oil out the dipstick
So I loosened the oil fill cap and let it sit there and sure enough it's bouncing all over the place so I'm assuming I'm in for some major engine work
But I've read a little about some possible turbo or air compressor issues causing the same problems.
Thing is the motor starts easy runs cool and gets good milage which to my mind is not indicative of that kind of cylinder blow By

So you saying it will be cumming out soon for a major??

[Doe69936]

Originally Posted by Seriousracer

So you saying it will be cumming out soon for a major??

Well I'm not sure yet after taking out the 2 gallons and letting it blow out some more from the dipstick it seems to have stopped and the pressure has gone down

[Lkn4it]

Take the old seal to a bearing supply.

[Booyah45828]

If you have blow by(dancing oil cap), it's not caused by a high oil level. The reason you get no oil out the breather is because it likely has mesh or baffles to keep that from happening.

Maybe you can latch the dipstick down in some fashion. I'd rather see that then you running the oil level below full.

I've never rebuilt a 5.9 cummins. No liners to swap so we normally just threw them away and grabbed a low mile unit from the salvage yard.

[Doe69936]

Yeah I've ruled out the low oil idea so no point running low.
what I'm hoping for is the turbo seals leaking and blowing air into the crankcase.
If not well the 8.3 is supposed to have sleeve liners but I've never done a rebuild guess there is a first time for everything

[Booyah45828]

You're right, I was thinking you had a 5.9 for some reason.