Cam & Aux Belt Tensioner Noise, Recorded.

Tourershine

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T6 Master
So it's been widely reported that VW are aware of an issue with certain year/vin number Transporters that are developing noisy tensioners.
I noticed a while ago that mine was starting to sound a bit noisy on start up when cold, but the noise would slowly disappear as the engine warmed up. The last day or so it's been getting worse, so I recorded the noise this morning and popped into Parkway Leicester to show one of the techs. He confirmed that this is the noise of a faulty tensioner and it would be covered under warranty :)

My T6 is now booked in for a new tensioner, which will include a new cambelt and all the parts associated with a cambelt change, all under warranty. Fantastic service and efficiency from Parkway as usual.

My T6 is a 2017 and it's on 70k

I thought i'd post the clip of the noise for others to use as reference. You can hear the whine/squeal immediately after I fire up the engine.


Ignore the following:
Heavy breathing (Blocked nose)
Squeaky door opening (fixed that now)
Noisy wipers (screen was frozen)
Socks :whistle:
 
Before I had my Cambelt change I had that same noise for 2 years and was told by my not so helpful van centre that is was just a characteristic of the engine :(, total waste of breath.
 
The tech recognised the sound instantly and said it was a timing belt tensioner before I said anything to them.
They said Volkswagen were well aware of the issue and called it officially a 'TSB' (Technical Service Bulletin) that basically meant that if the same fault had been reported 5 or more times in different dealerships, it automatically gets flagged as a potential issue. There were no arguments, he listened to the video I took whilst stood next to the Service desk, confirmed what it was within a few seconds of hearing my van start up, and that it was a warranty issue, and got it booked in.
They also confirmed it was a very common problem.

Is the noise a precursor to anything more serious happening?

As in the tensioner failing and potentially the belt breaking or also failing? It wasn't said in so many words, but it was clear it needed replacing asap.
 
Tensioners in general either seize or get lots of play/fall apart. Either is not good for the cambelt, each giving a slightly different path to possible catastrophe! One the belt will friction burn till it snaps the other will cause slack so the toothed belt can jump.

That said if one has been noisy for two years.....
 
Can someone post the same but with an engine without this issue. I am struggling to pick out the noise.

Pete
 
Can someone post the same but with an engine without this issue. I am struggling to pick out the noise.

Pete

The general clatter of the diesel engine is normal. It's the high pitched consistent squeal under that diesel rattle. I get why people cannot separate the two though. It's all noise.
 
I have 2 T6 going in for warranty repairs tomorrow :-

2018 104 ( 8k miles) for exactly the same noise as your video Vw Assist diagnosed it as Auxillary drive belt and tensioner fault ?

2018 204 dsg 4M ( 18k miles) Egr Flush again !! last done in June.

With the T5 I could tell if one was near me without seeing it by the rattle they all made, with the T5.1/t6 I need to listen for squeeks/ groans and no end of strange noises.
 
Mine had squeal and I recorded it but it sounded more like the belt than a pulley bearing to me, so I put some candle wax on the thin edge of the belt and the sound went away completely.
 
The general clatter of the diesel engine is normal. It's the high pitched consistent squeal under that diesel rattle. I get why people cannot separate the two though. It's all noise.

Got it thanks (mine doesn’t sound like that :thumbsup:)

Pete
 
So it's been widely reported that VW are aware of an issue with certain year/vin number Transporters that are developing noisy tensioners.
I noticed a while ago that mine was starting to sound a bit noisy on start up when cold, but the noise would slowly disappear as the engine warmed up. The last day or so it's been getting worse, so I recorded the noise this morning and popped into Parkway Leicester to show one of the techs. He confirmed that this is the noise of a faulty tensioner and it would be covered under warranty :)

My T6 is now booked in for a new tensioner, which will include a new cambelt and all the parts associated with a cambelt change, all under warranty. Fantastic service and efficiency from Parkway as usual.

My T6 is a 2017 and it's on 70k

I thought i'd post the clip of the noise for others to use as reference. You can hear the whine/squeal immediately after I fire up the engine.


Ignore the following:
Heavy breathing (Blocked nose)
Squeaky door opening (fixed that now)
Noisy wipers (screen was frozen)
Socks :whistle:
I had almost exactly the same symptoms, noise-wise and temperature related.
But after performing some checks I have discovered the shift of alternator tensioner pulley in relation to the belt itself(obviously disregard visible wrench socket)
Screenshot_20200130-005627_Gallery.jpg
As with increasing temperature the noise was disappearing I kept on ignoring the symptoms until I got to this stage:confused:
20200103_152730.jpg

20200103_152755.jpg

Once I replaced my alternator belt and its tensioner the noise went away:thumbsup:
Screenshot_20200130-005612_Gallery.jpg
Screenshot_20200130-011930_Gallery.jpg
€90=£76 well spent and invested:)

Lesson for future reference, any concerning symptoms should always be diagnosed asap and never ignored.
 
I had almost exactly the same symptoms, noise-wise and temperature related.
But after performing some checks I have discovered the shift of alternator tensioner pulley in relation to the belt itself(obviously disregard visible wrench socket)
View attachment 59449
As with increasing temperature the noise was disappearing I kept on ignoring the symptoms until I got to this stage:confused:
View attachment 59447

View attachment 59448

Once I replaced my alternator belt and its tensioner the noise went away:thumbsup:
View attachment 59450
View attachment 59451
€90=£76 well spent and invested:)

Lesson for further reference, any concerning symptoms should always be diagnosed asap and never ignored.

I can see what you're referring to, but are you saying the belt went out of alignment because of that tensioner failing, or is it out because the belt has failed?

Plus, now I can see your picture of a tensioner, it's not hard to work out which part is failing. Look at the water corrosion marks coming from the adjuster bearing.
 
Last edited:
The original cause of my issue was alternator belt tensioner wear. Basically it wore out its own "guiding slide" and that wear allowed the pulley to drift/shift out of alignment. But that misalignment is only visible/present when tensioner is deflected(belt is sitting on it). As a result of only 3/4 of the belt width being in contact with the pulley the belt itself has split and therefore started to produce "squeaking type" noise.

I think I have the photo of this wear on the tensioner somewhere, once I find it I will post it here:thumbsup:

Just to clarify even further I haven't noticed that shift in first place and I have replaced the belt only on my first attempt. Next day I have performed my own verification inspection and I have discovered tesioner pulley shift.

Photo below shows new belt and old tensioner after 1 day of driving the vehicle.
Screenshot_20200130-005627_Gallery.jpg
It is the same photo I have posted before but I wasn't precise enough in my previous post, sorry:thumbsdown:
 
My squeal comes from the belt rubbing on the tensioner inside guide wall. Look at the photo and circled you will see a gap on the outside(green arrow) but it's touching on the inside(red arrow).
As this tensioner has v guides the belt can only sit in one place, so either the belt is too wide or the tensioner is badly designed and the inside guide is too narrow?


upload_2020-1-30_9-36-10.png

Does anyone else have a close up of the tensioner pulley?
 
My squeal comes from the belt rubbing on the tensioner inside guide wall. Look at the photo and circled you will see a gap on the outside(green arrow) but it's touching on the inside(red arrow).
As this tensioner has v guides the belt can only sit in one place, so either the belt is too wide or the tensioner is badly designed and the inside guide is too narrow?


View attachment 59456

Does anyone else have a close up of the tensioner pulley?

Or your tentioner is worn, forcing it off centre.
I will take a shot of mine shortly.
 
The original cause of my issue was alternator belt tensioner wear. Basically it wore out its own "guiding slide" and that wear allowed the pulley to drift/shift out of alignment. But that misalignment is only visible/present when tensioner is deflected(belt is sitting on it). As a result of only 3/4 of the belt width being in contact with the pulley the belt itself has split and therefore started to produce "squeaking type" noise.

I think I have the photo of this wear on the tensioner somewhere, once I find it I will post it here:thumbsup:

Just to clarify even further I haven't noticed that shift in first place and I have replaced the belt only on my first attempt. Next day I have performed my own verification inspection and I have discovered tesioner pulley shift.

Photo below shows new belt and old tensioner after 1 day of driving the vehicle.
View attachment 59455
It is the same photo I have posted before but I wasn't precise enough in my previous post, sorry:thumbsdown:
Sorry for continuing off topic, but it might be useful for others and this is very easy to diagnose from the top(once the bonnet is up;)).
Photos of my faulty alternator belt tensioner below.
20200130_123446.jpg
20200130_123348.jpg
20200130_131251.jpg
 
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