turbo shaft play

[l1ttle_d3vil]

how much play should there be on a turbo, non-bb s13 t25g?
i can't measure it, but I'd guess its around 0.5 - 1mm side to side and end to end movement. fins don't rub on the compressor or anything.
it blew a bit of smoke previously, and some oil in the compressor inlet.

on the weekend i stupidly managed to get the timing 180º out which made a loud noise out the exhaust is this likely to have damaged the turbo even more?

also, im running the t25g on 12psi (hits around 15 before coming down), if I get it rebuilt is it likely to handle 12psi reliably? or should I not bother and swap it for a t28?

cheers
-matt

[Akane]

You can't just guesstimate it as more often than not it's inaccurate

but if there's oil out the compressor then it's shot already, oil seals are gone for sure. Not sure about the bearings inside, it might be pretty dead already.

I wouldn't bother with a rebuild, just get a geniune GT28RS and be the man. Spool of a T28, but 30+ more hp. But more suited for 2L engines.

I don't know if the 180degree jobbie has broken it. The T25G can run 12psi no probs.

As with all turbos that's not built for high volumes of air but forced to push so - the wheel overspeeds and the bearings and seals starts to cry.

[evil_si]

more than 0.25mm of end float and its no good
there should be some axial play -side to side but not heaps.

personally i wouldnt bother rebuilding, id get a new turbo

[l1ttle_d3vil]

You can't just guesstimate it as more often than not it's inaccurate

i realise that but its the best I can do.
definitely more than .25mm of end float

most of the time its perfect, but when it smokes it really smokes, and I doubt it would pass a revin test as is.
is there a cheap (even if temporary) fix to reduce the smoke?

[Akane]

is there a cheap (even if temporary) fix to reduce the smoke?

No.


Oh wait, yes.

Disconnect the oil feed to the turbo. That'll cost you $0

And how temporary? That I don't know, it depends on how quick the shaft will seize.

[l1ttle_d3vil]

what sort of labour is involved in just doing the seals?

[evil_si]

any decent turbo repairer wont just do the seals, the seals arnt just the problem,

the excessive wear is what has worn the seals, do the seals and they will fail just as quick,

only way to reduce the smoke is replace the turbo or blank old one off.

[l1ttle_d3vil]

ok so if I'm replacing the turbo, what are my options without needing a retune? can I get a t28 and run it on the same boost without any issues, even if the turbo specs are a bit different?

also, if I fit a t28 with the same compressor/exhaust sizes as the t25, will it have similar spool or be slightly laggier due to being bigger?

thirdly, if I were to run a BB turbo, the oil lines would need altering correct? as the bb turbos need restrictors don't they?

thanks for the input guys.

cheers
-matt

[Bazda]

Just buy a masterpower GT25 off me.

[l1ttle_d3vil]

ok was getting to that, but it still doesn't answer my question

[Bazda]

ok so if I'm replacing the turbo, what are my options without needing a retune? can I get a t28 and run it on the same boost without any issues, even if the turbo specs are a bit different?

also, if I fit a t28 with the same compressor/exhaust sizes as the t25, will it have similar spool or be slightly laggier due to being bigger?

thirdly, if I were to run a BB turbo, the oil lines would need altering correct? as the bb turbos need restrictors don't they?

thanks for the input guys.

cheers
-matt

If you change turbo is is more than likely you will have to change oil lines.

If you run a T28 the tune will need to change a little. The t28 wont have the same compressor or exhaust as the T25. As the comp wheel and exhaust wheels are bigger. Maybe you think having the a/r the same means its the same size. But no.

[l1ttle_d3vil]

cheers, PMd.

[Akane]

You'll need to retune due to changes in engine VE if you get a different type of turbo.

[steve murch]

max end float on any t2 series turbo of any sort should be no more than .003" or .065mm.
bearing clearance on the od is .0025" and id .0005".
unless its a gt25 s15 unit