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Discussion Starter · #1 ·
Its been a while since I posted, but I have been trying to figure out this little problem. Oil has been leaking out of the compressor side on two of my turbos. It has been leaking through the inlet and blowing oil towards the intercooler. The first was a cheap chinacharger. So I figured it was the build quality. I made another thread about changing the turbo. It is a PTE gt3251b and I have had it on for a few months now. But the problem persisted within a few days of driving. And I get the occasional smoke after a long idle or cruising. No smoke under heavy decel(high vacuum) So I think the piston rings are fine. The engine has about 6000 miles on the rebuild. I have to do a compression check to get some numbers.

After some research on this and other forums, I found that the most common problem with oil in the compressor housing is due to bad pcv valves that are routed from the valve cover to the intake tract pre-turbo. However I do not have an intake pipe going into the turbo inlet. And my pcv and oil catch can have been routed like this:



And here is what the leaking oil looks like:





Here are some other issues I have considered but not sure is the culprit:

Improperly routed pcv to catch can.
Too high oil pressure(turbo oil inlet does have a restrictor in place)
valve seals(head had a valve job done at the same time as the engine rebuild)
bad bearings and seals on the turbo compressor side, no sign of oil leaking on the exhaust side.

Perhaps I am over thinking the problem and it may be something small. But my first attempt to fix this will start with the rerouting the pcv lines and getting it to route back into the intake manifold. Although my BOV is occupying the old pcv vacuum port because anything smaller and I get compressor surge. Which I think is not enough vacuum in small diameter line to open the bov.
 

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your catch can setup aint right

i dunno if thats killin your turbos though....oil feed and return okay and unkinked? sure you didnt surge those turbos to kill them?
 

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Discussion Starter · #3 · (Edited)
The way the diagram is the way it is now(as I am trying to figure another way to route it back into the intake manifold), before I had the the open end of catch can going into the original port for the pcv on the intake manifold. But doing that left me with t-ing into another vacuum source for the tial bov which didnt open all the way and you could here compressor surge. I didn't drive it much longer after hearing that.

As for the oil return, the hose return does not have much of a bend to. Think half a "U". Plus I have a small clamp on the bend to keep it from kinking.

I do plan on rebuilding the turbo, but have heard of others doing the same and still having the problem.
 

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I had the same problem when i was running a ball bearing turbo. I did a ton of reading. From memory, most sources were saying. 1. Too much oil pressure. 2.Oil return not 'vertical' enough. and 3.Wrong size restrictor. (even though mine had roughly a 1mm hole).
 

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The way the diagram is the way it is now(as I am trying to figure another way to route it back into the intake manifold), before I had the the open end of catch can going into the original port for the pcv on the intake manifold. But doing that left me with t-ing into another vacuum source for the tial bov which didnt open all the way and you could here compressor surge. I didn't drive it much longer after hearing that.

As for the oil return, the hose return does not have much of a bend to. Think half a "U". Plus I have a small clamp on the bend to keep it from kinking.

I do plan on rebuilding the turbo, but have heard of others doing the same and still having the problem.

I dont think your pcv is the problem, you dont have to vent it back into intake. it you return going to oil pan or the block. i think thats the problem. a slight disproportion in that return bend will cause oil to come out through the compression. if tat return bend is lower than the stock drain and then come up. it will alway do that. you can either raise the turbo up or run the return to the oil pan
 

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Discussion Starter · #7 ·
if tat return bend is lower than the stock drain and then come up. it will alway do that. you can either raise the turbo up or run the return to the oil pan
The oil return does go straight down with no sharp bends into the oil pan. I'll get a pic of that soon.

Its used, and in need of a rebuilt. However I had this problem with the other chinacharger, right out of the box. But from my understanding, its usually the oil seals on the exhuast side that go first, not the compressor side. And as said before there is no sign of oil in the exhaust side, yet it still smokes from time to time.

The nut is there, kinda hard to see but its there. :lol:
 
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