K04 shaft end play, how much is OK?

[bnoon]

I've got a newly rebuilt/modified K04 and wondered how much shaft end play the K04 should have. Take a look at my video... does it look excessive to you? How much should be normal? I know the ball bearing turbos have tighter clearances, but still... seems like it should be less. Looking for facts here guys, if you know where I can find specs on what it should be that would be awesome.

YouTube - k04 shaft play

YouTube - k04 shaft play

[kingpin748]

I'm always in favor of a little shaft play. But too much, like everything else, is not a good thing.

[bnoon]

Well, I was editing my link... take a look.

[Darksun280]

My stock turbo which has been to hell and back and had zero shaftplay whats so ever when it came out my car. Take that for what its worth.

[bnoon]

damn...

[Tomas]

I think from your video you are talking about radial tolerance, not axial. Dude, I could not tell you specifically what the tolerance is on the K04, but on much larger turbos, the tolerance is 2-5 hundreds of a millimeter (0.02-0.05mm), This tolerance is called the runout. I would say yours is too high. Don't take my word for it though. As I said, no idea what the K04 is supposed to be.

[SharkDiver]

My stock K04 was like that when I took it out.My re-woked K04 didnt have much play at all when it was new but now it has some play in it after about 8k miles now.

[Tomas]

Oh, if you want to meassure the tolerance you will need a vice and a metric dial gauge, or vernier gauge, with an articulated extension attached to a magnetic support. Take the turbo, secure it via housing or flange in the vice, attach dial gauge device somewhere on the vice, and put the tip of the needle onto the compressor or turbine wheel edge. Now turn the shaft. If the is more than 0.05mm play while the shaft is turning sitting on the bearing I'd say the shaft is bent.
If shaft is straight, wiggel the rotor while it is static so you can get a reading on the play between bearing and shaft. Here again, if you more than 0.05mm there is something funny with your bearings or the diameter of the shaft.
What kind of work did you get done on your turbo?Any thing on the rotor itself like clipping shit ? or just stuff on the housings?

[bnoon]

Originally Posted by Tomas Oh, if you want to meassure the tolerance you will need a vice and a metric dial gauge, or vernier gauge, with an articulated extension attached to a magnetic support. Take the turbo, secure it via housing or flange in the vice, attach dial gauge device somewhere on the vice, and put the tip of the needle onto the compressor or turbine wheel edge. Now turn the shaft. If the is more than 0.05mm play while the shaft is turning sitting on the bearing I'd say the shaft is bent. If shaft is straight, wiggel the rotor while it is static so you can get a reading on the play between bearing and shaft. Here again, if you more than 0.05mm there is something funny with your bearings or the diameter of the shaft. What kind of work did you get done on your turbo?Any thing on the rotor itself like clipping shit ? or just stuff on the housings?

The shaft isn't bent, it just scared me how much the shaft moved compared to the ball bearing turbos I've had before in other cars. From what I've been able to find out so far, tighter is not necessarily better for bushing turbos. To tight and the bushings can seize up. Dry seals and bushings also allow more movement, with oil it will firm up a bit. The shaft has no noticeable thrust movement, so all is well.

Clipped exhaust side with a larger compressor wheel are the main mods, ceramic coated as well.

[ptperformance]

Add some oil to the center section and it should tighten up a good amount. I sent you a PM on this as well, thanks.

[wassup61]

That amount of shaftplay is considered within tolerance for a dry journal bearing turbo. If you have any issues let me know.
-Jeff at PG

[bnoon]

Originally Posted by ptperformance Add some oil to the center section and it should tighten up a good amount. I sent you a PM on this as well, thanks.

Yup, got it and provided the information to others above that this is within normal tolerence.

Originally Posted by wassup61 That amount of shaftplay is considered within tolerance for a dry journal bearing turbo. If you have any issues let me know. -Jeff at PG

Thanks for confirming Jeff.