Howling noise from turbo and no boost

[220bhp]

I have just heared from CR turbos,not good news ether the turbo shaft is bent with exstensive damage in side the turbo dew to they say overspin, £695 + vat to fix it. This is a brand new turbo and has done very few miles which they find hard to beleive so I have asked them to send a report on what might they think would cause this.
In the mean time I gess its time to do a few sums and make my mined up on what to do.

[GazzaG60]

so boost leak is a possability as i thought. id have a good check of all pipes and diverter and wastegate

was the turbo primed before fitting?

[220bhp]

I have performed two boost leak tests and that includes removing all the boost pipes. After the first one[which found found no leaks] the second leak test was done after refitting all hoses with new clips,this included vacume hoses. I also changed the dv and the n75 from my s6 which ran fine on them.

[GazzaG60]

strange one then.

a mate had a so called recon unit for a volvo that lasted about 2 weeks. similar issues.

[220bhp]

I have had the turbo confermed as originl borgwarner.

[urS6Tom]

Sorry to hear about this

I've just had a brand new RS2 turbo and manifold fitted so will be watching the post mortem with interest!

[HMS-S6]

I may be dismissed at talking rubish but, could it be caused by turbo stalling when shutting the throttle?? Perhaps from a faulty diverter valve not opening properly/enough maybe? Just a thought!

[S2central.net]

Is the wastegate opening and shutting properly ?

[220bhp]

Wastegate has been of and all checked out working fine

[newsh]

The car has done about 450 miles since fitting these items and boost was very good in the begining, a little too good as it was over boosting/spike to 2/2.1ing in 4th and 5th
then cutting the boost then climbing and so on,it pulled like a train in first three gears,I have checked the wastegate diaphramby sucking on it and it appears to hold vaccum but could it still get stuck open,if so how do I check this.

This is what you said in an earlier thread.

[220bhp]

Thanks for the reminder John, the waste gate has been of the car twice now and has been checked for problems, its ok including the diaphram.
John I beleave you had an rs2 setup on a 3b did you experiance any problems in the early stages what was different about your set up to mine and what boost levels where you seeing.

[220bhp]

Can anyone tell me if the wastgate on an s6 is the same as the 3b.

[twoqu]

Lou,

Some info here when John had some trouble.

http://www.s2forum.com/forum/showthread.php?t=33768&highlight=wastegate

I looked at this recently:
034 145 705B 3B
034 145 705E ABY/ADU
034 145 705B AAN
So it would seem that they at least share the same part number. Why the ABY/ADU has a different number I am not sure.

[220bhp]

Thanks for that Robin I will check this to make sure.

[220bhp]

I have now checked the wastegate and it is a 34mm s2 wastegate with a standard s2 spring. Also checked the travel and it is approx 16mm, not the 6mm that newsh had,the diaphram is also intact and working.
I just got the turbo back from CR turbos, they have done a fantastic job very impressed with there help and service, only problem is they forgot to pack there report along with the damaged parts but I should get them tomorrow.
My only problem is I still dont know what is causing the overspin as I beleave I have now checked just about everything.