Play in gt17 wastegate
Turbo Mini Forums

I'm not sure if this is normal but with the wastegate actuator removed on my gt17 there seems to be a lot of play between the sleeve the actuator arm runs through and the shaft for the arms.

there is no evidence of soot around where is pokes through the turbine housing but I can't believe with that much play (2-3mm sideways) that it will not blow.

How much play is acceptable in this sort of situation?

cheers

James

I don't know what is acceptable but I have a "scrap" GT1752 in pieces at the moment (along with a couple of GT1749V (s), see my other thread with pictures of both) and the play on the wastegate shaft is about 1.5mm side to side at the bushing. This actually equates to 5mm lost travel on the actuator because of the bell crank on the shaft. If a new bush could be fitted, I would, but you can't as the bell crank is welded onto the end of the spindle. I don't think there is even a bush in there anyway, I think the spindle runs directly in the cast iron of the exhaust housing.

Having said that, because of the spherical bearing on the wastegate flap itself, it seats perfectly despite all the excess play.

How much exhaust gas will leak out is another question - the one I have in bits is so knackered, there is carbon/soot everywhere :)

The "equivilant" spindles on the GT1749V (s) have no play, but they aren't having to move a heavy wastegate.

EDIT - typos

Edited by Rod S on 18th Sep, 2011.

Schrödinger's cat - so which one am I ???

I am sure that when Wil had my GT17 rebuilt the bust in the wastegate was replaced for this reason. I remember have a debate with the guy rebuilding it on if it was necessary. Whatever the outcome it was marginal benefit having it replaced.

I think that if you are running a second hand turbo then just use it. If you start replacing bits now you will end up doing a full rebuild.

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