Belt squeal - help

[Itguy]

Hi everyone

Have noticed that our gti has started squealing the six aux belt a bit when pulling away from standstill with the air con on and working hard.

It's a dsg (if that matters) and I changed the belt (not tensioner) about 3 months ago. If I switch the air con off the squeal stops/doesn't happen.

When it does squeal it's only for a second then it stops, but it sounds bad though.

I've tried some belt slip spray this morning but hasn't really seemed to help although it's very hard to spray the inside of the belt easily.

I also had my air con compressor replaced under warranty last year, around November time.

Any other thoughts? Tensioner need replacing maybe?

Thanks

[skard]

I'd look at the alternator clutch pulley too

[Itguy]

Ok - is there an easy test for it to see if it's good?

I'd kind of ruled it out as the belt/pulley is silent when the aircon is off - is this a mistake?

[skard]

It should only spin one way, I changed mine as a matter of course when I got the car.

On a previous car I had a rumble at tickover, putting aircon on changed the noise, it was the clutch pulley.

Does it have a genuine belt on? Only mentioning as I have had them from motor factors before and they are 5mm longer for instance.

[Itguy]

Interesting - I don't think it is a genuine belt, no. Can't remember what make it is, I think I picked it up off ebay.

Well if the belt is coming off for me to test the pulleys then I will fit a new belt too - got to pop to the dealers for something else too.

It should only spin one way, I changed mine as a matter of course when I got the car.

On a previous car I had a rumble at tickover, putting aircon on changed the noise, it was the clutch pulley.

Does it have a genuine belt on? Only mentioning as I have had them from motor factors before and they are 5mm longer for instance.

[doylebros]

I'd look at the alternator clutch pulley too

As he says ^^^^+ watch this

http://m.youtube.com/watch?v=fyosuYbPxr4

[Itguy]

Nice one, I'll check this out on ours. I did actually notice our tensioner moving up and down a bit and I was thinking I'm sure that doesn't look normal.

Could well be the answer

I'd look at the alternator clutch pulley too

As he says ^^^^+ watch this

http://m.youtube.com/watch?v=fyosuYbPxr4