Turbo seal or something else?

[hounddogs!]

Under mild boost (generally 10-15 psi, 20 max) I was getting the huge blue cloud from the tailpipe. Assumed a bad turbo seal, and the problem went away with a different turbo in place. The 'new' turbo is only set for about 12-13 psi, so I'm not totally sure that I wasn't blowing oil out of the motor due to the higher pressure.

If the 'leaky' turbo has absolutely no slop axially or radially, do I still assume it's a seal and send the thing off for a rebuild? I'd like to be more than 90% sure it's the turbo before I mail it away.

TIA

 

[Reggie West]

You have not determined if you are pressurizing the block at the same boost levels yet. Run the new turbo at 15 to 20 psi and see what it does. MAKE SURE you will not exceed the limits of the injectors by doing it.