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-   DIY Turbo Discussion (https://www.miataturbo.net/diy-turbo-discussion-14/)
-   -   Turbo seal leakage (https://www.miataturbo.net/diy-turbo-discussion-14/turbo-seal-leakage-18547/)

sergei 03-20-2008 09:12 AM

Turbo seal leakage
 
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):vash: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!

Braineack 03-20-2008 09:15 AM

does it still leak now?


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

Zabac 03-20-2008 09:16 AM

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

Saml01 03-20-2008 09:59 AM

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

sergei 03-20-2008 10:45 AM


Originally Posted by Braineack (Post 230698)
does it still leak now?


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

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??


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
I will do!


Whats if its not the lack of restrictor causing the oiling but rather the pressurized crank case not letting oil drain properly?
This is why I will adress both: restrictor and pressurized crank. I will go whit that setup:http://beesandgoats.com/boostfaq/PCV_turbo_2fit.jpg

Serge

sergei 03-20-2008 10:55 AM

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

Braineack 03-20-2008 11:07 AM

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

http://www.boostedmiata.com/technical/catch_can.jpg

sergei 03-20-2008 11:21 AM


Originally Posted by Braineack (Post 230776)
plumb both the breather and pcv line into the dry sump tank and call it a day.

http://www.boostedmiata.com/technical/catch_can.jpg

Yes but there is no vacuum that way...

cjernigan 03-20-2008 11:32 AM

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

Braineack 03-20-2008 11:40 AM

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

Saml01 03-20-2008 12:10 PM


Originally Posted by sergei (Post 230757)
This is why I will adress both: restrictor and pressurized crank. I will go whit that setup:http://beesandgoats.com/boostfaq/PCV_turbo_2fit.jpg

Serge

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.

Braineack 03-20-2008 12:14 PM

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


im sure that will solve the problem.

Zabac 03-20-2008 12:32 PM

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

sergei 03-20-2008 12:48 PM


Originally Posted by Braineack (Post 230820)
some turboz need restrictors, especially with a -4an line.....


im sure that will solve the problem.

I hope so, thanks for your support!:)

sergei 03-20-2008 05:55 PM

Update!
 
???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:
http://images3.hiboox.com/images/1208/zxme2owd.jpg
http://images3.hiboox.com/images/1208/4glqabym.jpg

But my turbo was pretty clean with no oil around the turbine and in the "exhaust of the wastegate":
http://images3.hiboox.com/images/1208/wzhnngj5.jpg
http://images3.hiboox.com/images/1208/ugu3all3.jpg

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:vash:
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)
http://images3.hiboox.com/images/1208/fog03q7g.jpg

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

Serge

sergei 03-20-2008 06:02 PM

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

cjernigan 03-20-2008 07:25 PM

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.

sergei 03-21-2008 08:15 AM

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....

mazda/nissan 03-21-2008 10:35 AM

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

Saml01 03-21-2008 01:58 PM

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


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