Strange belt squeal

spurs · Apr 26, 2012

Hi All,

I have a belt squeal at the moment on my 300tdi with just the one serpentine belt and like to think i have isolated the belt as the problem as with abit of wd40 applied the noise go's. The thing that is confusing me is the fact that when the wd40 wears of when im driving the squeal comes back but only when the engine is reved as when idling it's not making a noise. so is it the belt or one of the pulleys/tensioner. Is there any way of telling if its the tensioner bearings etc?

many thanks
Kyle

discool · Apr 26, 2012

Are you sure it's the serp belt as they are toothed so don't slip therefore don't squeal. these belts do have a replacement life around 75,000miles so when was your last changed.

spurs · Apr 26, 2012

Well Im guessing thats its the serpentine belt because as i apply wd40 to the belt the noise stops.....
I had a new belt put on about 10,000miles ago.
I forgot to mention that the noise started arfter coming done a muddy/very wet farm track the other day.

Kyle

Paddy474 · Apr 26, 2012

Might be crap in the grooves of the pulley wheels, I had that once.

I cleaned them out by holding a wire brush lightly against each of the wheels in turn while the engine was idling.

Paddy

barmatt · Apr 26, 2012

Do a search for "the penny trick" it has cured many a squealing 300tdi.

discool · Apr 26, 2012

This will help you maybe..http://www.landyzone.co.uk/lz/f38/300tdi-squeeling-belt-penny-trick-64595.html

Tony S · Apr 26, 2012

I agree with^^^

spurs · Apr 26, 2012

Many thanks, will giv that a try. will update when iv done it.

kyle

Dippypud · Apr 26, 2012

spurs said:
Many thanks, will giv that a try. will update when iv done it.

kyle

If no joy, check the alternator pulley, it can squeal like a stuck pig when it's on the way out.

but with WD40 the tension is less, so it quietens...wierd

thebiglad · Apr 27, 2012

discool said:
Are you sure it's the serp belt as they are toothed so don't slip therefore don't squeal. these belts do have a replacement life around 75,000miles so when was your last changed.

No they're not. They are grooved but that doesn't stop them slipping. Are you sure you're not confusing the cambelt (which is toothed) with the serp belt?

thebiglad · Apr 27, 2012

spurs said:
Hi All,

I have a belt squeal at the moment on my 300tdi with just the one serpentine belt and like to think i have isolated the belt as the problem as with abit of wd40 applied the noise go's. The thing that is confusing me is the fact that when the wd40 wears of when im driving the squeal comes back but only when the engine is reved as when idling it's not making a noise. so is it the belt or one of the pulleys/tensioner. Is there any way of telling if its the tensioner bearings etc?

many thanks
Kyle

Hi Kyle, there are two different lengths of serp belt for TDi 300, make sure you have the right one.

Too short and it will wear out the bearings of everything connected, too long and it will be sloppy and noisy.

Quoting your VIN to the belt supplier should get you the right one. Belts are cheap enough to replace so why not just change it? Then you'll know your belt is ok.

spurs · Apr 27, 2012

Right Update.....

Had a hell of a time trying the penny trick as someone had managed to cross thread the threads on the tensioner pulley, but anyway. tried the penny and it makes no diffrence.
I See that "thebiglad" quoted the alternator pulley bushes etc but surely if it was this then why when i apply wd40 to the belt the squeal stops....!

Im confused lol

Kyle

thebiglad · Apr 27, 2012

Put on a new belt and NO wd-40, ever !!!!!

spurs · Apr 27, 2012

thebiglad said:
Put on a new belt and NO wd-40, ever !!!!!

LoL i know as i was spraying it on i was thinking "hang on this is solvent based isnt it.....D'oh"

Yeah think thats the next thing to try. I'm not being stupid by thinking that it cant be anything else can it when i spray the wd40 on the belt...

Kyle

The Mad Hat Man · Apr 27, 2012

cos wd40 allows it to slip :doh:

discool · Apr 27, 2012

thebiglad said:
No they're not. They are grooved but that doesn't stop them slipping. Are you sure you're not confusing the cambelt (which is toothed) with the serp belt?

Of course it's grooved, that's because I haven't looked at my belt in years and don't have a cam belt.
Perhaps the wrong belt was fitted. there's two lengths of belt for the V8 engine also.

The best info yet is fit a new belt

davesdisco · Apr 27, 2012

i had the same symptoms mine turned out to foooked alternator bearings

Richard Martin · Apr 27, 2012

The belt drives the alternator, coolant pump and power steering pump, any of them, or the tensioner, could be foobar

spurs · Apr 27, 2012

Richard Martin said:
The belt drives the alternator, coolant pump and power steering pump, any of them, or the tensioner, could be foobar

Yeah but Richard the surely if any of them were fubared then surely the wd40 wouldnt have stoped the noise....

kyle

Fur Trapper · Apr 27, 2012

could be bearing's in the tension pulley

use belt dressing on the belt not wd40 good gosh it will just slick up the belt and slip more if that is the case

Strange belt squeal

Active Member

Well-Known Member

Active Member

New Member

Well-Known Member

Well-Known Member

Active Member

Active Member

Never Knowingly Understood

Well-Known Member

Well-Known Member

Active Member

Well-Known Member

Active Member

Well-Known Member

Well-Known Member

New Member

Well-Known Member

Active Member

Banned

Similar threads