I was wondering what is considered excessive shaft play. Every turbo i have seen has play if you grab hold of one end and wiggle it, but if you grab both ends and wiggle them in the same direction there is no shaft play; this goes for some used turbos and brand new turbos.

So how does one check for excessive shaft play ??? turbo gurus, please help

 

My KAI had 0 shaft play. It would not move side to side, or in and out.

Shaft play is when you grab the nut on the wheel and move it front to back. It should be very firm and solid. Sometimes you'll have a tiny, tiny, tiny bit of movement.. but if it's moving more than 1mm it's probably excessive. (someone please correct me if i am wrong) - The shaft play usually shows signs of a worn out bearing, The turbo shouldn't move side to side.. if that occurs.. you could start grinding the wheel on the housings.. and you'd be able to hear it when the turbo was spooling anyway. Also, when bearings go.. they usually cause the dynamic seal to leak and cause oil to go into the intake.. and also usually smoke.

 

I am no expert, but i would assume that it would depend on whether you have a ball bearing turbo or thrust washer turbo. I would think that a BB turbo would have very little end play where a thrust bearing would have considerably more play then a BB turbo... but then again I have no idea what I am saying... I'm just babbling

 

Nobody has any real information??? I know there are people on here that sell turbos for a living...