Hi!
I need your opinion.
Last summer I let a "performance shop" install my GT28R turbo set up. I noticed that I have some oil leakage in my downpipe. I've check the oil feed and there were no oil restrictor in there (-4an)My pressure runs between 20 to 80 psi.
So I will put a 0.035 to 0.04 restrictor there. Thanks for that thread: https://www.miataturbo.net/forum/sho...r+turbo+1%2F16
My turbo drain tube is a 3/8 inches and it is not clogged

My question: If my seal has been leaking for couple months, does it mean it is dead or should it works fine after my "mods".?? I heard that they don't usually "break".

Thanks!

BTW I will plug the pcv port on the intake and run a "vaccum" at the pcv port on the valve cover going to the turbo inlet (threw a catch can)...I don't want a pressurized crankcase anymore!

 

does it still leak now?


there's technically no seal, just a metal circlip, it's the pressure differentials that keep it from leaking.

 

sounds like you already know the answer...

in addition to what you want to do, i would pop the housing off and clean all the oil residue and reassemble it and see if it still leaks, you may not need a new one

 

Whats if its not the lack of restrictor causing the oiling but rather the pressurized crank case not letting oil drain properly?

 

I haven't give it a try yet, I'm still working on it. I was asking the question to know if I should upgrade right now for a gt3071??

I will do!

This is why I will adress both: restrictor and pressurized crank. I will go whit that setup:

Serge

 

I will have a catch can on both circuits.
I found the catch can from the compressor tools section in a home hardware storeat 25$ each!

 

plumb both the breather and pcv line into the dry sump tank and call it a day.

 

Yes but there is no vacuum that way...

 

Plum a line from the can directly to the intake tube after the filter. Done.

 

there's about 1-2 ~hg of vacuum in boost...

 

Why not try one at a time, preferably starting with the PCV. I have read many posts where people say running a restrictor is not always optimal. Dont know why, dont ask. Maybe clogging.

 

some turboz need restrictors, especially with a -4an line.....


im sure that will solve the problem.

 

most BB turbos need restrictors when running other than OEM feed line for example
they dont need as much oil as regular turbos...

 

I hope so, thanks for your support!

 

???I removed the turbo, ext. wg, exhaust manifold this afternoon and surprise!!!
At first I thought my turbo was leaking some oil and this is why there was a crust of carbon in my downpipe:



But my turbo was pretty clean with no oil around the turbine and in the "exhaust of the wastegate":



But look at the carbon builup at the exhaust side of the head?!?(3mm narrower than on the exhaust manifold (Begi log style))...no carbon buildup in the exhaust manifold, in the turbo...but a lot of carbon crust in the head and downpipe
I rebuild my engine last year, overbore it to a 1.9L, pauter rods, wiseco pistons, reroute, standalone SDS, 12.1 A/F at WOT, 14-15 on cruise, RC injectors, compression 180 all the board (cold, checked yesterday)


What the f**k is goin' on?!?
Any ideas, help appreciated. I think I will need to remove the head and make it cleaned...

Serge

 

Could that result from a pressurized crankcase?? The PVC I utilised was dead...

 

Yes. A pressurized crankcase will keep your rings from sealing, keep your oil from draining out of the turbo as well as some other things.

 

Can someone tells me if that carbon builup on the exhaust port is considered normal?
Thanks very much for your help! Very appreciated.

If I can avoid to remove the head for a cleanup....

 

i've got a carbon build-up on the back of my car so feel fortunate i don't think that it will hurt the head too much other than being dirty

 

Seafoam it when you get everything reassembled. it may help.