# What went wrong with this TDI turbo?



## ac9000 (Nov 6, 2008)

Hi, 
This turbo came from my 2001 Golf GTTDI (115bhp). It was a reconditioned unit that lasted only a few hours. Both supplier and fitter are blaming each other. Any definite answer as to what caused this would be helpful to say the least. The part failed while out on a test drive in the care of the mechanic carrying out the work, but since I supplied the part I'm the one left to foot the bill.
The shaft is snapped and the veins are all ripped to pieces. Could a weak shaft or other turbo component be to blame or is it more likely foreign object damage? The housing shows signs of where the veins have dug in.
The fitter pointed out that a nut was missing from the shaft at the end where the damage occurred, he is blaming this missing nut as the reason for the failure. The supplier is blaming foreign object damage, saying this nut would have spun off at the moment of impact. He said the nut would be in the intercooler. The car was stripped down, and to my knowledge no nut was ever recovered. The supplier won't repair under warranty.
Any help greatly appreciated.
Thanks.




















































_Modified by ac9000 at 11:34 AM 11-6-2008_


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## RedDevil (Sep 21, 2001)

*Re: What went wrong with this TDI turbo? (ac9000)*

my $0.02, mechanic should inspect the part before installing it.
Any pictures of the bearings?


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## ac9000 (Nov 6, 2008)

*Re: What went wrong with this TDI turbo? (RedDevil)*

I agree with you on your point.... I'll get pics of bearings up shortly.


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## 91gti_wolfsburg (Mar 15, 2005)

Look @ the wear on the shaft journal in this pic. 
Not saying that it caused the failure, but that kind of wear does not occur in only a few hours use.








Can we get pics of the end of the shaft where it broke, both sides.
Sometimes you can tell how it broke by examining the broken ends.


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## ac9000 (Nov 6, 2008)

*Re: (91gti_wolfsburg)*

Thanks for your comment. Just to clarify, even though this is a reconditioned turbo, the wear on the shaft should not be as much as is seen in the photos given the timescale from fitting to failure?
Attached are both ends of the shaft, one is concave shaped and the other is convex shaped.
Attahed are several more photos, one shows some type of fracture or damage.



















































_Modified by ac9000 at 10:50 AM 11-6-2008_


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## 91gti_wolfsburg (Mar 15, 2005)

OK, the pictures of the shaft ends tell me that it was a torsional break, meaning that it was twisted off.
Thats correct. The amount of wear on those journals is waay too much for just a couple of hours use.
When it was recon'd if they had re-used that shaft, it should have failed inspection for tolerances, and never been sold.
If you look closely at the shaft ends where it broke you can see spiral shaped ridges of metal. This was twisted off, almost like someone stuffed a screwdriver into the inlet when it was spinning at full boost.
As far as the broken compressor housing back plate, look at those breaks, those were also caused by some sort of rotational force.
The thrust bearing looks _OK_, is the side we are seeing the side that was up against the impeller?
Now, the packing nut should have been kicked back towards the air filter or it should have been found wedged into the compressor housing. The gap that it would have had to fit through to make it all the way to the intercooler is too small for the nut to pass.
I have seen these come off before, but they just rattled around inside the intake chewing up the impeller blades, and never caused a catastrophic failure like this.
I want to say that the shaft was bent at some point, the impeller dug into the compressor housing and it caused the shaft to twist off.
This would explain the excessive wear on the bearings, a bent shaft.
EDIT: Or come to think of it, it [the wear] could have been caused by a severe imbalance. Which at 120,000RPM doesn't have to be that much.


_Modified by 91gti_wolfsburg at 11:21 AM 11-6-2008_


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## ac9000 (Nov 6, 2008)

*Re: (91gti_wolfsburg)*

Thanks very much for such a comprehensive reply. I can't answer what way round the bearings were as the turbo came back to me in pieces. Would you say I should go back to the supplier questioning the shaft wear and can we rule out foreign debris as the cause?


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## g60vwr (Apr 9, 2000)

*Re: (ac9000)*

Did your mechanic mention anything about it was really fast until the turbo blew....


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## RedDevil (Sep 21, 2001)

*Re: (g60vwr)*


_Quote, originally posted by *g60vwr* »_Did your mechanic mention anything about it was really fast until the turbo blew....


You stole my line!








The bearing damage looks bit excessive for just few hours of use.
The only thing I question is the shaft breaking like that as if something made that impeller stop very quickly. (missing nut??)
Because I don't think these bearings had that much play to do that.


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## 91gti_wolfsburg (Mar 15, 2005)

^^THis is why I think maybe the shaft was bent.
As the turbo spooled up, the bend in the shaft got worse, causing an imbalance, which made the wobble worse, which in turn caused the impeller to get stove up, and finally caused the weak spot in the shaft to give out.
I think that the damage to the impeller happened after the shaft gave out. Meaning that while the nut was most likely missing, the turbine was sloppy in the housing banging back and forth, and then when the shaft finally gave out, thats when the fan hit the isht. Quite literally.


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## 91gti_wolfsburg (Mar 15, 2005)

*Re: (ac9000)*


_Quote, originally posted by *ac9000* »_Thanks very much for such a comprehensive reply. I can't answer what way round the bearings were as the turbo came back to me in pieces. Would you say I should go back to the supplier questioning the shaft wear and can we rule out foreign debris as the cause?

I am not too sure where you should go with this.
I would question the bearing wear, and how uneven it is, and how it looks like it was severely out of balance(re: the shaft wear).
It is really hard to ufck up a turbocharger install.
I am pinning this one on the manufacturer.


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## ac9000 (Nov 6, 2008)

*Re: (91gti_wolfsburg)*

Thanks very much for that, your theory makes more sense than those given by the supplier and the fitter.
The supplier has told me that if I get an independent report done by a competitor saying it was parts failure, he will refund me and pay for the report. Is it likely that I could obtain such a report based on the evidence? Obviously I'd ship the item down to wherever for inspection.
The supplier seemed sure that everyone would agree with him, but then I suppose he would say that!


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## 91gti_wolfsburg (Mar 15, 2005)

You dont even have to go that far.
Talk with someone who is experienced in working with metals, an engineer would be able to support all of the things I have said. Perhaps even a certified welder.
All you have to do is to get them to type something up saying what Ive said, and you are golden.


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## ac9000 (Nov 6, 2008)

*Re: (91gti_wolfsburg)*

I had an engineer friend look at the turbo today and he agreed with your theory that the shaft had broken prior to the blades smashing into the housing. I then emailed the seller and informed him of the issues that have come to light. He never gave me much of a reply other than that any report pointing blame at him must come from a turbo specialist and not just any engineer. Not sure of his reasoning here.
Guess I'll have to email a few companies see if I can get one on side.


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## dumped_gti (Dec 16, 2003)

*Re: (ac9000)*

Was the oil feed line replaced at the time of the turbo installment? I have seen this numerous times.. This looks like the turbo was starved for oil, and then the shaft broke.. You should ALWAYS replace the oil feed line.. Your mechanic should have told you this., If they know their VW's..


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## ac9000 (Nov 6, 2008)

*Re: (dumped_gti)*

yes oil feed line replaced, this was a condition of the warranty.


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## RedDevil (Sep 21, 2001)

*Re: (ac9000)*


_Quote, originally posted by *ac9000* »_yes oil feed line replaced, this was a condition of the warranty.

Was the oil feed line primed (filled with oil ) prior to the install?


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## ac9000 (Nov 6, 2008)

*Re: (RedDevil)*

I wasn't there at the time of fitting so have no idea whether or not it was primed. The turbo came with substantial fitting instructions which included this step, the garage said they followed all the steps. Do you suspect a lack of oil also?


_Modified by ac9000 at 1:14 PM 11-7-2008_


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## antichristonwheels (Jun 14, 2001)

*Re: (91gti_wolfsburg)*

exactly. There were obviously problems with the shaft. Who was the supplier? 
Send it to Jeff, he has years of experience with turbos. He can tell you exactly what happened. When the original supplier welches on the deal, you can get one from Jeff:
http://turboauto.biz/


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## ac9000 (Nov 6, 2008)

*Re: (antichristonwheels)*

Thanks very much for the information, only thing is I'm in the UK, will have to see what the shipping will cost, might be bit expensive. Anybody know a good contact in the UK?


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## RedDevil (Sep 21, 2001)

*Re: (ac9000)*


_Quote, originally posted by *ac9000* »_I wasn't there at the time of fitting so have no idea whether or not it was primed. The turbo came with substantial fitting instructions which included this step, the garage said they followed all the steps. Do you suspect a lack of oil also?

_Modified by ac9000 at 1:14 PM 11-7-2008_


You can see the brass residue on the shaft. Shouldn't be there. unless in was running dry at some point.


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## cant get a password (Sep 24, 2004)

*Re: (RedDevil)*

I ran a garret vnt 15gt on my corrado g60 and my diverter valve failed and compressor surge snapped the shaft.Just an Idea but doesn't explain the excessive wear.


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## 91gti_wolfsburg (Mar 15, 2005)

*Re: (cant get a password)*


_Quote, originally posted by *cant get a password* »_I ran a garret vnt 15gt on my corrado g60 and my diverter valve failed and compressor surge snapped the shaft.Just an Idea but doesn't explain the excessive wear.

Lucky for him diesels are incapable of producing compressor surge since they do not have throttle bodies. http://****************.com/smile/emthup.gif


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## matchew (Apr 11, 2006)

*Re: (ac9000)*


_Quote, originally posted by *ac9000* »_Thanks very much for the information, only thing is I'm in the UK, will have to see what the shipping will cost, might be bit expensive. Anybody know a good contact in the UK?

http://www.turbodynamics.co.uk/


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