Turbine housing leaking oil
 

So I thought my turbo was blown ( Borg Warner S363 ) because it was leaking ( dumping ) oil into the turbine housing. I replaced the turbo with a Borg Warner s362sxe.
Sure enough it's also smoking and leaking from the center section/ turbine housing

My thoughts are either too small of a drain line or something is causing excessive crank case pressure. The car has no pcv just a catch can. Any help is awesome.

Cheers,

Tony

What size are the oil feed and return line?
Some people had used -4 for feeding no restrictor just fine, but the return needs to be -12.
I use -3 and -12 no smoke or leak at all.
I don't know about the crank case pressure though.

Simplest way to fix is remove oil filler cap and replace with a filter or breathable element and at a minimum 10 AN drain positioned properly with a straight shot to the oil pan.

Proper drain configuration includes large enough drain size -10 (5/8") or larger tubing that smoothly bends into the crankcase WITHOUT A BELLY. If oil pools in the tube then it requires pressure to push it into the engine. The fitting/adapter that attaches to the turbo drain can be restrictive and some need to be ported.

here's what you want
https://cimg8.ibsrv.net/gimg/www.rx7...ca0b27bcc9.jpg


What is your oil pressure? Too much pressure may require a restrictor.

Crankcase pressure can be an issue. I made a custom oil filler neck that has a -10 AN fitting and a hose that connects to a well vented catch can. I also fitted a -8 hardline between the rear oil drain in the block (not used with a single turbo) to the base of the filler neck to provide a vent path during high G cornering.

Here's a picture. if you look carefully you can see the -8 fitting on the other side wrapped with electrical tape to protect it from damage.
https://cimg5.ibsrv.net/gimg/www.rx7...87a0556132.jpg

I'm using 4 an feed with no restrictor and was using a 10 an return. I'm thinking of bumping to a 12 an return and maybe adding a restrictor. The car will run for about 2-3 minutes before oil starts to weep out of the turbine housing.

The return was very straight with a small bend of the turbo and a small bend to the block. I'm worried the factory drain fitting on the front cover is causing a restriction. I cut it down and ensured there is no drooping in the line.

I also ran the car with the oil cap off which would alleviate crank case pressure issues so I think I've got it nailed down to either a restrictor, bigger return line, or both. Oil pressure is around 45 at idle. Any idea on what size restrictor to run? There is a lot of differing opinions on what to do run. Thanks for all of the help so far!

Tony

I had all sorts of issues with different restrictors while running my S362SXE with a 4 AN feed line (120 psi oil pressure on startup and above 3,500 RPMs and that's with 10w40 oil).

I eventually purchased the freelance turbo oil feed restrictor and gauge. All I did was start the motor cold and while looking at the gauge on the turbo feed line turn the set screw until the gauge read 60 psi (half the pressure to the engine). It fixed all my issues by reducing the pressure. Honestly just guessing on the correct size restrictor is a gamble. restrictor too small and you could be at 0 oil pressure on the turbo and not know it. Too big and you may not reduce pressure at all. On my the freelance restrictor kit, you'd be shocked at how little of play there is in the set screw between 0 psi and full pressure....

Oh freelance restrictor is amazing. I'm currently running 20w50 too so that could be causing drain slow down while potentially also causing hi oil pressure. Thanks for the tip!

I have 362 sxe too. I used -3AN at the turbo feed and -12 at the drain with unmodified oil presure and never leaked or smoked

I'm going to start with the Freelance regulator! Anyone have any recommendations on building a -12 an return line?

Thoughts on this return line?
https://cimg2.ibsrv.net/gimg/www.rx7...81e9a5c675.jpg
is that too sharp of an angle to close to the turbo? Still having issues even after the restrictor install.

Cheers,

Tony

Any help is appreciated!

Thats good

That's enough fall and and shouldn't cause any problems? This has been a struggle and I'm really over continually removing the return line haha

That should be good.

Is that the drain you've been running?