Oil pressure blowing out turbo seals?

[SupraSean]

Ok 92 7mgte Fresh rebuild about 1k miles ago,(new bearings, rings, seals etc) started up the car with my t61 i used last year(had about 2k miles on it)started and the turbo seal on the exhaust was blowing oil like crazy, didnt do it last year but i figured just a fluke something happened while it was sitting. so i put on a known good ct26 just to drive it home from my school. Start it up with the ct26, runs great no smoke at all. pull out of the shop, go down the hill, still no smoke. come back up the hill and get into about half throttle on stock wg psi. pull back into the shop and i see smoke so i shut it off. i had an oil leak coming from my softline kit. so i try to doctor it up.I flip the drain flange around so its not so kinked. Start it up and its smoking out the exhaust again. i verified it was the turbo oil seal because there was no oil in the manifold outlet. Oil pressure wasnt crazy high something like 15psi at idle. how can it have two known good turbos blowing the oil seals. Could it still be a fluke?? any input guys would be much appreciated. thanks.

 

[WI88Supra]

I assume you have a good sized oil return line and that it is a straight shot down to the pan?

I haven't seen this issue on supra's much at all. On mazdaspeed cars it's as common as BHG's on ours and the answer is to make a custom oil restrictor bolt.

 

[87supraguy]

I assume you have a good sized oil return line and that it is a straight shot down to the pan?

I haven't seen this issue on supra's much at all. On mazdaspeed cars it's as common as BHG's on ours and the answer is to make a custom oil restrictor bolt.

crazy blow by? pcv not working properly. this was a issue i ran into with my 91 turbo mx6.... granted i was using a cheap ebay turbo i kept blowing oil seals on these turbos because my they idiots i hired to do the "turbo kit upgrade" and they decided blocking off the pcv valve was an approriate mod. IT"S NOT!!! i saw this and hooked it up properly and it fixed everything.

 

[MDCmotorsports]

Check the pcv system. And for the love of God, and the trillionth time.....TURBOCHARGERS DO NOT HAVE SEALS

 

[87supraguy]

no seals? really good to know. so if the turbos leak oil? maybe not a big enough return line to drain oil fast enough, not a small enough restictor on the feed line, or bad pcv system. the turbo internals maybe fine? just trying to put pieces together for my knowing.

 

[raysupra]

try buying a .5 micron filter and putting it on the oil feed.. it will Help make your oil pressure more consistant flowing into the turbo and clean.. also make sure your drain line as Straight down as possible and a 45 to the block.. you don't want Any goofy angles.. purly gravity fed.

I have no idea why the PCV system would have anything to do with your turbo.. so dunno what their talking about.. its for crankcase pressure which needs a good constant intake source..

What have you all done to your oiling system? anything aftermarket?

 

[87supraguy]

...I have idea why the PCV system would have anything to do with your turbo.. so dunno what their talking about.. its for crankcase pressure which needs a good constant intake source..

What have you all done to your oiling system? anything aftermarket?

A crankcase ventilation system is a way for gases to escape in a controlled manner from the crankcase of an internal combustion engine. in other words if the pressure being built up in the crankcase has no where to go becasue of a bad/stuck PCV (positive crankcase ventilation) valve and wont vent it into the intake, it will find a way out by any means possible (which on turbo cars) will end up being the oil lines to the turbo... this was the issue i had on my mazda mx6

 

[raysupra]

ahh.. yea that could be a culprit then.. lol

 

[87supraguy]

... its for crankcase pressure which needs a good constant intake source..

btw a good intake source is need but not a constant one. that's where the valve comes into play. it's open under vaccuum (no boost) and closes under boost. hmmm which makes me wonder... maybe the PCV is backwards possibly? if opening while boosting then it would pressurize your oil system and could also blow oil through the turbo and possibly past the piston rings... it's only a $5 part easy fix give it a try and report back with any updates....

 

[raysupra]

You should have your PCV system vaccum on your Turbo intake. so i guess not constant

 

[MDCmotorsports]

Turbos have "dams" so to speak of. They are piston rings, not SEALS. Seals are rubber.

 

[JStoked]

Turbos have "dams" so to speak of. They are piston rings, not SEALS. Seals are rubber.

Ahh thank you for clarifying that for me sir. Had the same prob with my tdo6. But the oil drain line was kinked pretty bad so im pretty sure that is my prob.

 

[SupraSean]

pcv not being vented was pushing oil out of the turbo. also had a leaking feed line