gwhammy

What would cause the oil seal on the cold side to start leaking? The top turbo sat. and is blowing alot of oil out of it. I have a couple of extra center sections to change it out with but it seems odd for it to start leaking like that. It is the top turbo on the setup, could pressure do it?

PourinDiesel

Yes excessive crank case pressure can cause a blown seal in a turbo or any other seal for that matter.
Also, another possibility is a worn thrust bearing. Check for in/out play on the shaft.
You can remedy the crank case pressure by installing/welding a bung onto the valve covers and using KN type breathers on top of each valve cover and that should remedy the issue.

I have also seen a turbo that has sat for a long time seep or leak oil from its center section into the compressor or turbine section if sat vertically (like on the floor) for a long period of time. Same turbo will not leak while running on an engine.

gwhammy

I hadn't thought of crankcase pressure but that makes since. With 270,000 on the motor and some right foot pressure alot of the time that is problably it. I have had trouble with the valve cover gaskets leaking so it adds up to the right answer. I'm guessing 40 to 65 lbs. of boost has compounded the problem and I did pull the trailer about 300 miles loaded when this all started to show up. It blew a boot off at the intercooler and I noticed oil but thought it was off of something else. Thanks for the info POURINDIESEL!