How does the turbo oil seal typically go?

smurfbus · 04-25-2011, 11:21 AM

Mine seems to be sweating oil INSIDE to the turbo up pipe so the oil goes through the IC and then smokes some.

I found this out by running the engine without the turbo connected on the cold side.

Oil came out from the up pipe but no oil came from the open compressor inlet? It did smoke some even now with this air bypass but that might be oil in the muffler. I dont want to run the engine without muffler.

The turbo is supposed to be a fairly low milage rebuild unit (changed because of smoke). My oil pressure is 90psi on cold idle and 60 psi warm idle and then 80psi at 3000 so does the oil pressure brake the seal if I install any new turbo?

There is a ball valve on the idiot light switch.

Any ideas on what to check? I'd like to get my oil pressure down some if it is correct. The oil pressure sender does not look easy to take out.

JFairman · 04-25-2011, 12:20 PM

According to a conversation I had with Bob at Durabilt Turbo a while back, a restrictive air filter can cause oil to breach the piston ring oil seal on the compressor side of the shaft like you are experiencing.
A small restrictive air filter or a dirty clogged air filter creates a negative vacuum instead of postive pressure at the center of the compressor wheel and behind the compressor wheel in the shaft area while positive pressure is being made at the exducer edges of the compressor wheel and turbo exit or outlet.

With that in mind I would clean all the oil out of the compressor housing and remove that somewhat dirty small K&N air filter and see what happens.

smurfbus · 04-25-2011, 12:29 PM

Thanks, didn't think of that.

Any ideas about the high oil pressure?

TurboKraft · 04-25-2011, 11:15 PM

In our experience, that little filter is too small for a 930. Cute, but too small.

smurfbus · 04-26-2011, 11:08 AM

It did smoke some and the oil kept coming out of the compressor up pipe even when the turbo was out of the loop though.

I wish I had a dwyer gauge so I could measure the pressure loss at the filter.

Could a cam housing oil line restrictor raise the pressure that much (60 psi warm idle)?

Any suggestions for air filter? Stock usually flows plenty but I don't have one and it could be hard to get here.