Been street tuning and ironing out the kinks of my build and ive been chasing a small oil leak cant seem to figure out. I have a used turbonetics t3 i think super 60? Didnt know the model exactly when bought. Moroso 4qt oil pan. 10an drain 45 off turbo to straight fitting into pan. Oil is not leaking out of return fitting when pulling return off. All feed fittings are tight and sealed.

After i drive around and do a pull i see a small pool on the center housing right below the bolt that bolts the center housing to the cold side compressor housing. it doesnt seem to be coming from the feed fittings and dripping down, its almost like its coming from those bolts. Is it possible if the seals were shot oil could be pushing out through those bolts?

The turbo had very minimal side to side shaft play and no front to back when i installed it.

This is a new build motor with less than 100miles on it btw.

 

Pics, if at all possible, would help.

 

even if you don't see any oil at the return line, there can be a drainage issue. Meaning, the oil is backing up and cause it to leak at the turbo CHRA.

Don't ask me how I know. LOL

 

Can take pics tomorrow of everything. Today i drained some oil out of my pan because previously i took the return off and oil came out. Theres no kinks or bends in my line its as gradual and downhill as i can get it. Theres no more oil coming out of return when pulling the fitting off.

i have a catch can setup modeled after the sticky’d one on the forums here and i am getting a little oil in the catch can so i know its somewhat working. I dont think crank pressure is causing it.

from looking at t3/t4 internal diagrams it looks like there is a seal that separates oil from going up to where the 4 housing bolts go so im thinking that seal may be on its way out.

i pulled off the intake filter and theres no oil on the inlet wheel or anything. From doing pulls and having someone behind me they say no smoke so im pretty sure its not the shaft seals, just an internal o ring of some kind.



These 4 bolts are where i seem to be seeing some oil pool below. So im thinking there may be a seal before those 4 bolts that is allowing oil to creep past.



This is from a t3/t4 rebuild. Not sure if turbonetics would have same seals but this is what im thinking is shot.

 

if anything, take pics of your fitting at the oil pan. I had to use a floor jack to "massage" the fitting upwards to eliminate the drainage problem I was encountering. When the car is jacked up from the front, the motor looks level and all is good. Once it's lowered back down, the engine is actually tilting forwards (CCW). If you look closely, the front side of the oil pan (where most folks weld/install their oil drain connector), it is NOT 90*. That's where the issue lies....most of the time.

 

Any oil in your intercooler pipes?

 

Did not check intercooler piping, but i will tomorrow and i will also check the angle of the return once the car is on the ground. Hadn’t considered that.

 

Yeah, right before I had the car dyno'd, I dealt with that BS. The oil return line looked good but I kept noticing oil at the CHRA. Had to tweak the oil pan fitting upwards and that solved the issue. All this within hours of going to the dyno shop. Talk about crunch time....lol

 

Like i mentioned i have a moroso oil pan, aluminum one with aluminum AN fitting for return...would be a little apprehensive to try and massage it to an upward angle

 

With car on ground i can see there is a small downward angle. However today i went out and did some pulls and there was a lot less oil on top of the center housing. Im thinking maybe its starting to seal itself a little

 

This is where i was seein a leak

 

the leak WON'T seal itself. Trust me. Remove the oil return line at the oil pan and carefully pry the fitting upwards with a floor jack. You don't have any other choice....besides re-welding that fitting. You sure that's an aluminum oil pan? Looks like steel to me.

 

You’re right it is steel, didnt know it was a zinc coating. Would heating the bung and trying to bend it up help? I feel like bending it from the an fitting risks mashing the threads or deforming the fitting somehow

 

use a piece 2x4 between the jack head and bung.

 

I didn't heat up mine and it worked fine. Just keep a close eye on the floor jack head while raising it. Honestly, it only takes a bit of force to bend the fitting upwards.

 

That oil return looks to flat going around the downpipe like that, easily could be the issue with a back up. Not so much with the steel oil feed line. The focus needs to go back ot the return line angle, and location of the fitting on the oil pan.

 

It looks like not enough return. Check some videos from turbolabamerica. What's the dia of the return. Get something like 12mm.

 

The FIRST issue is the bung angled downward. The return hose diameter is perfectly fine.. dafuq?!

 

OP likely has -10AN lines going to the oil pan. It's not the size of the line that is causing the back-up issue.

 

Yeah its 10an. I agree i wasnt super happy with the drain angle but with the downpipe theres no other way to route it. Right now ive got a 45 off the turbo to a straight end into the pan. I mocked the line up with a straight off the turbo and it looks about the same angle wise so i think im just going to have to bend the bung and leave it