Serp Belt area noise and tensioner variations

[nrobinson]

I’ve just begun investigating chirping and rumbling noise from the v belt area on my 2003 XC90 d5. Interestingly its much worse at idle – a few revs and it quietens down.

I’ve removed the tension on the belt but not removed it yet, but already suspect I have at least a failing power steering pump as there is play in the pulley / shaft.

I’ve not checked anything else yet including the tensioner, but whilst gathering info on what needs to be done stumbled across a number of worrying discussions, including some on this forum that discussed a problem where the serp belt can jump the bottom crank pulley, go through the cover and basically trash the engine when fouling the timing belt. The discussions were quite old but did suggest it was a common problem, so my first question is, in the passage of time is it that common!?

My next question which is related, is about the tensioner. From what I can see from the discussions I’ve read is that if the belt jumps its normally as a result of a failed tensioner when the spring has weakened and the pulley forced at an angle. One of the threads seem to suggest there is an older type of tensioner that was more prone to this. Is this correct?
At the moment mine looks ok visually

From what I can see looking at VIDA there appear to be two OEM part nos for the tensioner:-
31251252 for engines up to number 349808
31251251 for engines 349809 onwards.
..which even that looks odd as my thinking is the pns would be the other way around based on age.
Is anyone able to tell me what the difference is on these two options?

Thanks
Nick

[SwissXC90]

> The discussions were quite old but did suggest it was a common problem, so my first question is, in the passage of time is it that common!?

There were 400000 XC90s sold worldwide from 2006 to 2014. All engines.

Lets assume the D5, popular in Europe, but not in the USA, was only 30% of all sales. That's 120,000

From 120,000 vehicles sold worldwide, how many forum posts did you read about this "common problem" ?

I'd expect to see tens of thousands of posts if it is indeed a "common problem"
Indeed, I'd expect recall notices it is was that common.

I'm not saying it's not a problem, I'm just questioning the way you arrived at the determination that it is a "common problem"

[ltec]

Originally Posted by SwissXC90

> The discussions were quite old but did suggest it was a common problem, so my first question is, in the passage of time is it that common!?

There were 400000 XC90s sold worldwide from 2006 to 2014. All engines.

Lets assume the D5, popular in Europe, but not in the USA, was only 30% of all sales. That's 120,000

From 120,000 vehicles sold worldwide, how many forum posts did you read about this "common problem" ?

I'd expect to see tens of thousands of posts if it is indeed a "common problem"
Indeed, I'd expect recall notices it is was that common.

I'm not saying it's not a problem, I'm just questioning the way you arrived at the determination that it is a "common problem"

The common problem is that when someone comes onto this forum looking help that they are criticised instead of helped.
If the posts was removed that says only a volvo mechanic can work at a volvo and every other part but genuine volvo is crap their wouldn't be many posts left.
How dare he say an xc90 has a common problem and hurt everyone's feelings.
The only response he has got is this and no one actually trying to help him.
And to finish off your statement that your not saying its not a problem.
There is quite a few people on here looking for a little bit of help who haven't the money for main dealers etc and work at their own cars and all they get is criticism.

[ltec]

Originally Posted by nrobinson

I’ve just begun investigating chirping and rumbling noise from the v belt area on my 2003 XC90 d5. Interestingly its much worse at idle – a few revs and it quietens down.

I’ve removed the tension on the belt but not removed it yet, but already suspect I have at least a failing power steering pump as there is play in the pulley / shaft.

I’ve not checked anything else yet including the tensioner, but whilst gathering info on what needs to be done stumbled across a number of worrying discussions, including some on this forum that discussed a problem where the serp belt can jump the bottom crank pulley, go through the cover and basically trash the engine when fouling the timing belt. The discussions were quite old but did suggest it was a common problem, so my first question is, in the passage of time is it that common!?

My next question which is related, is about the tensioner. From what I can see from the discussions I’ve read is that if the belt jumps its normally as a result of a failed tensioner when the spring has weakened and the pulley forced at an angle. One of the threads seem to suggest there is an older type of tensioner that was more prone to this. Is this correct?
At the moment mine looks ok visually

From what I can see looking at VIDA there appear to be two OEM part nos for the tensioner:-
31251252 for engines up to number 349808
31251251 for engines 349809 onwards.
..which even that looks odd as my thinking is the pns would be the other way around based on age.
Is anyone able to tell me what the difference is on these two options?

Thanks
Nick

Pm sent

[TruckbusUK]

Originally Posted by ltec

Pm sent

Ah, so by posting a PM to the OP Itec (which will no doubt be helpful or at least your opinion) you are effectively behaving in exactly the same way as the other forum members you so love to moan about.

Go on give yourself a treat, tell everyone your opinion/resolution rather than a PM ... some may find it helpful or at least informing to aid with the resolution to similar issues, after all is this not the point of forums to give opinion and help to all?

[ltec]

Originally Posted by TruckbusUK

Ah, so by posting a PM to the OP Itec (which will no doubt be helpful or at least your opinion) you are effectively behaving in exactly the same way as the other forum members you so love to moan about.

Go on give yourself a treat, tell everyone your opinion/resolution rather than a PM ... some may find it helpful or at least informing to aid with the resolution to similar issues, after all is this not the point of forums to give opinion and help to all?

Helping the person who needs help is not the same as criticising him. Unlike you who posted not to help him but to criticise me for trying to help him. Maybe that answers your own question why it was a pm.

[TruckbusUK]

Originally Posted by ltec

Helping the person who needs help is not the same as criticising him. Unlike you who posted not to help him but to criticise me for trying to help him. Maybe that answers your own question why it was a pm.

Dear me, got out of bed the wrong side this morning, I offered no help as I have no experience of the issue or suggestions that my have helped the OP, hence I didn't offer any. You obviously do, but preferred not to share with the whole forum, and keep your knowledge private and only voice your criticisms, again not really the purpose of forum discussion.

[nrobinson]

Looks like I’ve unwittingly started a debate – however just for the record thank you SwissXC90 and Ltec for your feedback.

I am not personally stating its a common problem - just that when I went hunting for info, there were discussions and youtube videos stating that it was a common problem. There was also someone seeming to offer an aftermarket protection guard of some sorts but I’ve never seen any pics. I guess its the old case of when trawling the internet you are going to find 'the bad'.

I think i now need to focus on what is causing the chirps and rumbling. I’ve since removed the belt which I suspect is old and stretched a little but generally looks in good condition. Pulleys all seem to be running freely but there does seem to be a small amount of play in at least the PS pump and on the tensioner pulleys.

Short of swapping out components one by one, which could get expensive – would be interested to hear of any further diagnosis suggestions.

Also interested in the question in my original post on the differences in the two tensioner part no’s?
Rgds
Nick

[wynnj]

I have read of instances of the Serpantine belt taking out the timing belt on this volvo forum, but not necessarily on the XC90 sub group. The D5 has been fitted to numerous models (I've currently got a V70, S60 and XC90) all with essentially the same engine although there are other differences between the Euro 3 and Euro4 versions. Volvo made some changes to the auxilliaries tensioner at least once along the way, but the service procedure remains the same.
Having experienced a timing belt failure on my first S60 (probably because the volvo specialist I used didn't change the tensioner even though I was charged for it when I had him do the belt change) I sympathise with the original enquirer especially as I also had an auxilliaries belt jump off the cranshaft damper pulley when the rubber compound failed, fortunately with no other consequences.
To help allay the enquirer's fears if the Timing belt is changed as per recommended schedule or sooner, including the tensioner and idler pulley, and the auxilliary belt and tensioner is changed at the same time there shouldn't be any problems.
If you pay someone to do it always ask for the old parts back; I unfortunately didn't, but I change them myself now.

[owenfackrell]

I have had the idler pulley fail, in fact it happened twice. I don’t know why it went the second time but the replacement was fine after that. Both times cashed the belt to fail, second time it was accompanied it smoke but no other damage. The indicator was ‘power system services urgent’ message as the alternator stopped.
The third pulley I got from Euro car parts but was the OEM manufacturer for Volvo (IPA or similar) for about a 1/3 of the price.
When the first one went it started by making a noise that changed with the revs. It was a whining noise. It’s hard to discriminate be but once you know what it is you will hear it on other cars.