AUDI A6 C6 2.0 TDIe - TENSIONER STUD TO CHANGE OR NOT?

[Novica]

Hello,

In near future I have intention to change Timing belt and all other things with it on my new A6 2.0 tdie (with 175000km on it, engine code CAGB). I noticed that in some kits include tensioner stud. Do I need to replace it or not?

I have never changed on my A4 (1.9 TDI 96kw AVF engine, 2004), timing belt was changed 2 times and stud remained same (car had 260000km on it when I sold).

Nice to hear your opinions and experience?

Novak

[B5NUT]

I've head of these failing over time, so I would change it. Stick "tensioner stud failed" in Google and you will see why it should be changed.

[Novica]

Already two days I am passing over net, and I read plenty threads in different forums (skoda,vw, etc) about PD engines which suffered snapping of this stud. Mostly happened after changing of timing belt.


There are reasons to change it and not to change. In begging (and I know, because I had PD engine) the timing belt kits did not include this stud but now some kits include and some not. I am not sure if original kit include it or not. Does dealer change it or not. Someone is telling that old stud can be reused if tension pulley is not overtighted after fitting it, especially if it is first time changing the belt. The other problem rise if you change the stud, you must proper tight it if it is loose or overtighted then you will get problem very soon.

What to do?

[dan2485]

If you get the bolt in the kit replace it unless you have a calibrated torque tester to check the torque wrench.

Your average torque wrench is normally out when set even if the wrench is calibrated every year.

Most professionals who use torque wrenches for accurate settings will check/setup the torque using a tester.

this would be a professional bit of kit

http://www.norbar.com/en-us/products...d/273/id/10970

[dan2485]

use lociite 222 to fix the stud to the cylinder head.

[Novica]

Thanks Dan,

To be honest, I use same torque wrench for last 10 years and I have never checked it. I am using it for wheels and for changing timing belt once on my ex passat, 2 times on my ex Audi A4 and I have intention to use now on my A6. But, all these stories about failure of timing belt are moving me away from this job. Anyhow, there is still time to make right decision.

I will keep gathering information about right procedure and see what is best to do.

Cheers

[B5NUT]

The mechanics I've worked with rarely use a torque wrench, and I've worked at Audi dealers and over the time I worked there I could count on one hand the amount of time a torque wrench was used, and never seen one used during a belt change. If you capable of doing the change yourself then get a copy of elsawin of the bay and do the job yourself. Also get the wrench calibrated or replaced, I just picked up a digital wrench from machine mart for £60 so they are not exactly expensive. If you do the job yourself then you know you have done the job right, and not cut any corners.

[Novica]

Today, I have checked my outdated ELSA (last models 2008) and I could not find torque for stud (I was looking on PD engine 2.0 tdi, and various models). On the internet, I found somebody mentioned that torque should be 15NM and to be inserted without any locking medium.

Does anybody know or have document where is stated torque of this stud?

Also, do I need to apply some locking medium as Dan advised or to tight it only to required torque? From other side, I read that if you apply any medium on threads(wet, greased, locking stuff) that can influence on torque.

Novak

[B5NUT]

It's 15nm for the CAGB engine code. Personally I would only use thread lock if it states so, and thread lock will not prevent the bolt from snapping.

[Novica]

My is CAGB, 2.0 TDIe, January 2011, manual transimition.

I do not have this facelift model on my ELSA. But, I read on net that this stud started recently to be changed, and instructions did not mention it before (even the timing belts kits did not include it). Now, whichever kit I found on net(Continental or Dayco), it includes tensioner stud which confirm that this stud should be changed.