For all of those who are experienced with the turbonetics t3/t4 i encourage your response.

I have a T3/T4 Journal bearing which ran fine for quite a while, after a couple months i started getting some smoke at idle and after investigation it appeared the turbo had a very deminished oil flow. When i pulled the inlet feed piece which has a small filter in it, the filter was clogged to hell so when trying to clean it up the filter piece broke out of the piece, i know this is used as a sort of oil restrictor also but since i didnt have access to a replacement piece i put in a standard .065 oil restrictor i had laying around. It worked fine for a couple days than started leaking oil into the end housings. Im wondering if the turbonetics restrictor that came with it was actually more restrictive than the .065 and its getting too much oil or if its some other problem. Just so you get a better idea im using a braided -10an return line tapped slightly above oil level in the pan, also feed line is -3an.

Any help would be appreciated. Thanks guys!

 

From what I've heard from Tnetics - the oil filter is less restrictive than a 0.65" restrictor. You may need to get better seals in there.

Can you post pics of your oil drain?

 

Unfortunately at work atm, but i can tell you its a constant slope, no pits in line, although it does sort of "spiral" downward but thats the first thing i checked was wondering if maybe it was too restrictive. Just curious how is your crankcase vent setup, is it just open? Ive heard from others it need sto be conencted to a vacuum source and may ahve problems with excess crankcase pressure if its just open, any truth to this?

 

Excessive crankcase pressure won't blow your turbo seals.

But yes it should be routed to atleast a catch-can or your intake.

 

Hmm interesting, so even if it was worn piston rings causing excessive crankcase pressure, that most likely wouldnt contribute to this problem? Still if its getting enough oil to go through the seals it seems maybe its the restrictor? What about crankcase pressure causing restriction on the oil drain, thus causing it to leak through the seals?

 

Crank case pressure shouldn't affect oil drain at all.

A few things that I know which contribute to blown turbo seals are:

-Poor drainage
-Excessive oil pressure
-Not enough oil pressure
-Center housing clocked past 15*

Maybe you had too little oil in there? If it's a journal bearing turbo, it should be able to handle our oil pressures. I'm thinking the seals used to replace the turbo are crappy - or the restrictor you used was too much of a restriction.

 

Maybe you're confusing the effects of crankcase pressure on other seals of the engine? It shouldn't affect the turbo.

 

yea im thinking i need to pick up a replacement inlet piece with filter and have a local shop rebuild the turbo for me as im sure its the seals, ive tried my hand at rebuilding a turbo in the past and even with lining up compressor wheel and nut uising matchmarks, the thing was never really balanced properly and has some terrible shaft play after a couple months. Thats another thing on this turbo, it does have a fair bit of shaft play so im thinking its time to pay for a professional rebuild and balance.

 

That's a good idea.

Make sure your wheels aren't damaged - and if the housings are scored from the wheel/shaft play, you'll need to get those machined.

 

Last weekend when i looked at it wheels looked fine, maybe a tiny bit of scoring on compressor side, but none on turbine side.