Turbo Shaft Play...

[Samon]

Hello all,

My first post (I think... maybe not) over in the 'dark-side' of the forums...

I'm about to do the big RB25DE => RB25DE+T conversion, and I'm pretty sure I've got everything I need... only worry I have is with the turbo itself. It's a stock R33 RB25DET one, but there's a little bit of shaft-play. I've heard that it's okay to have a little bit of up/down movement, but no back/forwards (I guess you'd call it 'end-play' or something)... is this right? It moves about 3mm back and forwards... is it worth getting it re-built? What kinda prices am I looking at for that? I've done plenty of searching, but can only really find threads related to 'items for sale' adverting 'no-shaft-play' or 'minimum shaft-play' so far!

Cheers,

Sam.

[Guilt-Toy]

3mm? damn.

its totalled. not worth rebuilding it. buy a replacement for under $400

[DECIM8]

so your facing the wheel and you can pull it up and down or your facing the wheel and can move it side to side with 3mm of play?

if second one then yes its rooted.

[Samon]

so your facing the wheel and you can pull it up and down or your facing the wheel and can move it side to side with 3mm of play?

if second one then yes its rooted.

If I look directly into where the dump-pipe bolts on, i can slide it... in-and-out about 3mm

[DECIM8]

Wells thats better than moving side to side, but still its no good.. I know there is a screw on them anyone know if you can tighten the wheel? some strange key tho

[R31Nismoid]

Better than moving side to side? wtf?

Side to side is perfectly OK, every single turbo will have S-2-S movement even for a ball bearing turbo. Bush bearings move substantially more.

When the car is on, running with oil pressure this movement is taken up by the oil in the cartridge.

Front to back (or in and out) is the BAD movement of the lot.

[Samon]

Better than moving side to side? wtf?

Side to side is perfectly OK, every single turbo will have S-2-S movement even for a ball bearing turbo. Bush bearings move substantially more.

When the car is on, running with oil pressure this movement is taken up by the oil in the cartridge.

Front to back (or in and out) is the BAD movement of the lot.

That's the impression I was under. I'll have to have a look at it tonight when I get home, but how much movement (in and out) is okay?

[DECIM8]

I was thinking side to side movement of 3 mm is pretty big my turbo has none. but more to the point its pretty obvious I know little bout turbos

Edited May 27, 2008 by DECIM8

[Kinks]

Better than moving side to side? wtf?

Side to side is perfectly OK, every single turbo will have S-2-S movement even for a ball bearing turbo. Bush bearings move substantially more.

When the car is on, running with oil pressure this movement is taken up by the oil in the cartridge.

Front to back (or in and out) is the BAD movement of the lot.

From what I have picked up over the years, in a bush bearing turbo any axial (front to back, in and out) movement is bad because it means the thrust washer has worn out. Some radial movement is OK. In a ball bearing turbo, a very small amount of axial movement is OK. Radial movement is a bad sign.

That said, a friend's brand new ball bearing HKS turbo had about 3x more radial play than the stock item we took off. I was quite surprised but I guess they run wider clearances as part of the design.

Plenty of disclaimer on the above though, I have done 2 turbo swaps myself but never one due to imminent failure

[R31Nismoid]

The new turbo = no oil in it.

Turbo taken off car = some oil to pickup the slack.

Turbo off a car, same model etc probably should have less play (except if its worn and so on)

I've had my turbo's off, bush bearing, had a bit of play, same with my GT30

So one of each type, and both had side-t-side, the GT30 had less... but then we are talking MM here so its minimal overall

[Samon]

The new turbo = no oil in it.

Turbo taken off car = some oil to pickup the slack.

Turbo off a car, same model etc probably should have less play (except if its worn and so on)

I've had my turbo's off, bush bearing, had a bit of play, same with my GT30

So one of each type, and both had side-t-side, the GT30 had less... but then we are talking MM here so its minimal overall

Just had another look, much closer this time, and in reality we're talking about less than 1mm in/out play. This should be fine, right?

[R31Nismoid]

Yeah mate, not a problem

[skylinekid]

ok well i just turned arounds grabbed my brand new garrett t04z and it has side to side movement.... like every other ball beraing turbo that i have felt so wat until it starts making funny noises dont worry hahahaha

[GTS4WD]

As said before,

People freakout about shaft play..

You have to bear in mind that there will also be oil running through the turbo that will pick up some of the shaft play.

[nizmonut]

i was reading manufacturers manual the other day and browsed past this particular subject, factory manual says ideal maximum forward to back movement or thrust should be .8 of a millimeter.

Edited May 28, 2008 by nizmonut