Purchased a T25g turbo pulled from an S14 (?) a while back looking to be in great condition externally and with virtually no shaft play. Finally got around to fully disassembling it yesterday to check for and clean out any coking I could. Oiled it and put it back together and it felt great except that both before and after the disassembly and cleaning, if I put my finger over the oil feed and blew into the oil drain, there was a noticeable amount of air escaping from around the shaft on the exhaust turbine side.

I'm unsure if this will go away and seal when there is oil pressure on the ring seals, or if this is an actual issue that warrants new seals / shaft / whatever is letting air and potentially oil through. If anyone knows much about turbo rebuilds or just the turbo seals, Id appreciate the knowledge!

 

The seals aren't designed in a manner that will allow them to seal when you're blowing air through it with your mouth. I can't tell you your turbo seals are good but I can tell you your test shows you nothing useful.

 

Ok that’s a relief. I figured they might be designed that way, but just don’t have the background to know how those ring seals work. Luckily the rest of the turbo is in great shape so it likely is fine.

 

Totally broken. Just send it to me and i'll take care of disposal

 

For free? Generous of you!