2001 DF115 leaking upper end crank seal

[chinook06]

leaking some but not lots of oil from upper end crank seal. engine has 500+ hours runs great is not overfull on oil, crankcase breathers are not plugged although there was a small amount of foamy oil and condensate in the tube. seal appears in great condition with no areas of corrosion or rust on the crank or at least none that are contacting the crank seal. almost seems like a case of to much crankcase pressure causing the leak but saw no indication of what is causing it. any ideas or thoughts appreciated.

Thanks
Bob

[WEDOCQ]

Bob,
I am no mechanic, first off! I have your exact engine and have done a ton of research on them, and have learned of a few common problems. A big one is "engine holder corrosion". Do a google search on this one and you might be surprised! My engine, long story short (and apparently many others). On the port side of engine holder, there is a soft metal plug that accesses the exhaust. because of the type of metal used, it reacted with the aluminum, causing corrosion. This corrosion caused an internal breach of the wall between the exhaust and the crank case. In my case, it also caused water from a water jacket to seep into the crank case as well. In other cases I have seen, it just sends exhaust into the crank case, causing abnormal pressure.
Even if this is not your current problem, I would inspect the engine holder plug for corrosion.
-Shawn

[catacom225]

oil seal

If you have corrosion on the external engine pan plug it will blow outwards, If your broblem is enternal it will pressurise the engine

Why it dosn't blow out the breather pipe i don't know. Drain your oil and check for carbon deposits, my 140 had the same problem with crank seal.
Pulled engine off and found gasket between engine holder and oil pan was blown? , also good idea to do a compression test befor you start work

[chinook06]

thanks

The replies are appreciated and i will look into these possabilaties as the cause of my problem and will post as to what i discover.

[volvo5er]

Hi, i am bringing up this old thread because I have similar issue on 2005 DF115. A lot of oil is leaking through upper crankshaft seal. Does anyone know how to replace the seal or what could be the cause of this leakage.

Thanks in advance

[catacom225]

Crank Seal

First i would do is a compression test, dry and wet . Excessive pressure in the sump should be expelled from the breather one would think. The upper crank seal can only be replaced by splitting the block. How many Hours does your engine have, also good idea to check the engine holder as WEDOCQ suggested

[volvo5er]

Engine has 850 hours. The engine holder has already been fixed. Compression is 190 psi on all cylinders. Is there no other way to change the oil seal, is it only possible by removing the crankshaft?