Turbo Leak Help

[thehemi]

Let me try to give details w/o being boring...

I'm putting a SyTy turbo setup on my S10.
-4 AN oil feed line and -8 AN oil drain line.

Initial start-up, oil leaking (intake and exhaust).

Maybe -4 AN is too much of a feed line?
Installed a 0.073" nitrous jet as a restriction.

Start-up again, oil leaking (intake and exhaust).

Maybe my drain line isn't working the best?
It's in a slight "S" setup, similar to a Syclone.
I decide to run the drain straight into a bucket.

Start-up again, 3-4 runs of 2-3 min each, no leak!
(2-3 min each so I could recollect the drained oil.)
I think the turbo was dumping about 1 qt per min.

Re-route the drain line so it's more downward than
before -- goes under the xover now, no longer over.

Start-up again, oil leaking (intake and exhaust).

Positive pressure in the crankcase, perhaps?
So I decide to try running it w/o the oil filler cap.

Start-up again, oil leaking (intake and exhaust).

What gives? Some say my turbo is hosed. But it wasn't leaking
on the straight shot into a bucket. Unless THAT much flow w/o a
restriction might not cause the leaky turbo seals to get the chance
to leak, perhaps? Or I do have some kind of a pressure problem?

Any advice on where to go from here?

 

[Try Me]

Re: Turbo Leak Help

-4 isnt too big for a feed line, but the turbo may need a restrictor in the top. How much oil pressure are you making at idle? Is it a stock turbo?

 

[thehemi]

Re: Turbo Leak Help

-4 isnt too big for a feed line, but the turbo may need a restrictor in the top. How much oil pressure are you making at idle? Is it a stock turbo?

I put a 0.073" nitrous jet on the oil feed adapter coming out of the block.
Is there some chance that's different than putting one on the turbo itself?

I think my idle oil pressure is around 40-45 psi. Yes, it's a stock turbo.

I did an amateur rebuild of the turbo, so I don't guarantee it isn't hosed,
but the fact it didn't leak when running the drain into a bucket makes me
think the turbo could be okay? But maybe not?

 

[Try Me]

Re: Turbo Leak Help

Where is your oil leak when the oil return is hooked up?

I would say if there is no problem with the return dumping into the bucket, but there is when you have it hooked up then the problem is in the return. Maybe its getting kinked somwhere when its hooked up?

 

[thehemi]

Re: Turbo Leak Help

Where is your oil leak when the oil return is hooked up?

It's definitely coming out of the intake, and from the smoke
out the tailpipe I'm guessing it's leaking out the exhaust, too.

I would say if there is no problem with the return dumping into the bucket, but there is when you have it hooked up then the problem is in the return. Maybe its getting kinked somwhere when its hooked up?

When it had the "S" shape like a stock Syclone, there actually
was a kink on the final 90* bend. I thought that was the issue
at the time, but a re-route didn't solve the problem. Now it's a
more or less straight down with a gentle curve towards the pan
once it passes the crossover pipe.

My drain line connects at the front, passenger side of the pan.
I was sticking my finger in as far as I could after I drilled and
tapped it, there's no blockage as far as I can tell.

It does seem like the drain line must be the issue, but I cannot
route it any better than it is right now. Unless there's some kind
of pressure problem in my crank case? Which I'm not sure how
I can troubleshoot further?