Finally finished my home brew build using a Saab Garrett T25 turbo. I had to clock the turbo for my application which meant turning both turbine and compressor housing to fit my manifold. I have drilled the sump for the oil drain.
When I first ran the car, after a few minutes, the turbo was smoking between the turbine and the centre section of the turbo (no smoke at the exhaust). Looking underneath the turbo I could see oil weeping. I figured the second hand turbo I bought had damaged seals so I bought another second hand turbo. I didnt look as if it had any 'oil leaking' problems. I went through the process of clocking the turbo, fitting it and starting the car....after a few minutes, exactly the same thing happened, it starting smoking when the car was revved and oil started weeping from underneath the turbo between the exhaust turbine housing the centre section.
Am I missing something or have I just been unlucky buying two faulty turbo's??! Another thing Im thinking, does this particular turbo no like being clocked?

 

Is the oil feed hose attached properly? Maybe the threads are shot or you overtorqued it?

 

Where exactly is your drain tapped into (location). Sounds as if oil is backing up.

 

I have tapped the drain in the common place, bottom left side of the sump on the exhaust side of the engine. I had the same thought that the oil may be backing up.
I took the hose off the drain barb just to convince myself that oil was making its way down the hose and started the car briefly...its definately coming through.
Does the engine have to be vented in some way? If it isnt, could this cause the oil not to drain through the tapping?
Im convinced I have overlooked somethng as both turbo's had they same symptoms?!

 

Too much oil pressure going to the turbo?

 

what size restrictor are you using?

 

Restrictor?? Is that something to do with the oil feed line? I bought a braided oil feed line from BEGI which stated it was for a Garrett turbo. The thread didnt fit into the turbo so I adapted it by clamping a piece of fuel hose to the thread then clamped the other end of the hose to the original oil feed/bolt from the Saab (this is a hard line). I'll try and add a picture to show what I did.
Could I be supplying too much oil? When I watched the oil come out of the drain hose, there was quite a lot coming out.

 

you NEED one of these for garrett BB turbos. It will screw into the center section of turbo, which then will connect to turbo oil feed line. full oil pressure on garrett BB turbo no good. looks like this:

 

I use to have a Saab turbo........... and I used a 1/8 rivet it worked great !

 

Thanks for the help, will I have damaged the turbo seals without the restrictor? I only ran the car for a short time after noticing the oil weeping. Both turbos are from 15yr old Saab's, will they still be BB type turbos?
As for the suggestion of adding a 1/8 rivet, how exactly did you do it?

 

I had a journal bearing turbo years and years ago in my Corrado that blew the seals the same way, after about a week they fixed themselves after adding the restrictor. The turbo in my Jetta which did the same thing never recovered.