300 Tdi Belt Squeal - Penny Trick Warning

Hi Everyone,
Just taken delivery of my 300tdi (Delivery read just driven it back to Austria from UK in 28 degrees ahhh)
Developed a belt squeal, have had the belt off and tensioner (tensioner is stamped 2015 but a little play on the bearings is this normal?) cleaned the pulleys and of course squeal still there. Noticed he alternator was not lined up so adjusted that with a washer or two but still have the squeal.
Decided to try the 'penny trick' which I used a M10 washer - and the squeal disapeared BUT have a look at this picture and see how the belt is overrunning the water pump pulley.



So leads me to think is could be water pump pulley? Noise goes when the belt is spayed with water. Any ideas where to go next - thinking new belt first and then???

MFC said:

Hi Everyone,
Just taken delivery of my 300tdi (Delivery read just driven it back to Austria from UK in 28 degrees ahhh)
Developed a belt squeal, have had the belt off and tensioner (tensioner is stamped 2015 but a little play on the bearings is this normal?) cleaned the pulleys and of course squeal still there. Noticed he alternator was not lined up so adjusted that with a washer or two but still have the squeal.
Decided to try the 'penny trick' which I used a M10 washer - and the squeal disapeared BUT have a look at this picture and see how the belt is overrunning the water pump pulley.

View attachment 152795

So leads me to think is could be water pump pulley? Noise goes when the belt is spayed with water. Any ideas where to go next - thinking new belt first and then???

Click to expand...

Just buy a Gates belt.

Try some belt dressing spray. Takes a while to work, but completely cured the belt on mine.

Al2O3 said:

Just buy a Gates belt.

Click to expand...

+1 - buy the best, buy once - I had to replace a Gates matched pair the other day - they had worn out and the lack of adjustment meant the alternator wasn't getting enough urge under load .... date code on the belts was 1995, so I think a warranty claim is in order

Larry328 said:

Try some belt dressing spray. Takes a while to work, but completely cured the belt on mine.

Click to expand...

+1 - about a fiver on the bay for an aerosol = worth every penny

Thanks for the comments, short update. Just had a parts delivery and included a new Dayco belt - fitted and squeal is gone - for now. Maybe the alternator alignment has helped. See if it comes back!!

+1 on the decent belt. The Dayco one fitted by my garage when I had my timing belt changed was thin and started making a hell of a racket after only a few months.
I changed the tensioner which didn't really make much difference (was worth doing as the old pulley gearing had some play in it). I then noticed that I could make out the ribs on the smooth side of the belt, it had also stretched. Down to Halfords and got a new, different Dayco which was noticeably "heavier", no problems since..

MFC said:

Thanks for the comments, short update. Just had a parts delivery and included a new Dayco belt - fitted and squeal is gone - for now. Maybe the alternator alignment has helped. See if it comes back!!

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Give it a few days, just to take the initial shine off. Then it'll start to grip better and squeak better. Gates seem to have the compound just right.

I put a new dayco on mine when I got it and serviced it...started squeeling, thought it maybe a dodgy belt so fitted another dayco and it stopped, then not too long after...started squeeling, so I've just done the penny trick (using a penny) a few days ago and the squeeling is a lot less and now I'm waiting to see How it goes, maybe I need a gates belt???

Towsey

Don't believe this...did the penny trick and it got rid of about 90% of the noise, but then about a week ago the noise got a lot worse. Belt looks the same as before so I took the penny back out and the noise is back down to how it was before I put the penny in...can anyone explain???

Forgot to say, the inner (nearest engine) part of the belt runs at a different level to the rest of it, like the first 2 ribs are partly worn away so when looking across the flat side of the belt it dips down a bit for that portion

towsey956 said:

Forgot to say, the inner (nearest engine) part of the belt runs at a different level to the rest of it, like the first 2 ribs are partly worn away so when looking across the flat side of the belt it dips down a bit for that portion

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If the belt isn't running true, the V 's of the belt end up under stain inside the V's of the metal pulley. The rubber V's off the belt can be pulled off the back of the belt and end up well and truly stuck in the V's of the pullet wheel. This means that a replacement belt runs on top of the rubber stuck in the V's in the pulley wheel. You probably need to get the pulley wheel cleaned out with a small wire brush.

Cheers
All the pulleys are clean, I always do them when changing a belt and with this thing when it plays up and I take belt off for a look I do them for good measure. I'm sickvof putting new belts on every time I try sumat new

towsey956 said:

Cheers
All the pulleys are clean, I always do them when changing a belt and with this thing when it plays up and I take belt off for a look I do them for good measure. I'm sickvof putting new belts on every time I try sumat new

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Have you tried a Gate's belt yet?

Not yet, to be honest I'm worried about buying a fake belt in this fake rip off world as suppliers round me don't have them

towsey956 said:

Not yet, to be honest I'm worried about buying a fake belt in this fake rip off world as suppliers round me don't have them

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No idea what part number you need, but this is what they look like. LINKY

Thanks for that...I never thought they would be on amazon

I'd also like to find the actual issue with the vehicle. Nothing is visibley out of true but I don't know if they are prone for anything else

towsey956 said:

Thanks for that...I never thought they would be on amazon

I'd also like to find the actual issue with the vehicle. Nothing is visibley out of true but I don't know if they are prone for anything else

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It might not be visible, but something is out of true. There's a few pulleys there that all have to be perpendicular to to engine and parallel to each other. It's quite an ask. Given that and the tension the belt is under, it's hardly a surprise that a squeak can develop with a high friction belt. The Gates belts have a harder compound on the smooth side of the belt and so slide a bit rather than grip and then squeak as the Dayco belts seem to do.

Thanks for that
It seems to be the water pump pulley that's squealing I think, there is a slight possibility it's the alternatoer but I'm sure the the pump. So I don't know if this means it's that pulley or the one before if the one after that's out of keltor but damn it's annoying. The penny trick seemed to help to begin with but now it's making it worse. One thing is that if I get a gates belt and it stays quiet then very good, but it will not have solved the problem.
One thing I have noticed is that when I put the belt on that was on when I got it then it still stays quiet, only problem is that belts knackered and I can't see any writing on it...bugger

Ok so here we are again

I've got my self a gates belt at last from a local factors that's now selling them at £15

But I'm still keen to cure the actual problem before I fit this belt, so has anyone any info about this whole problem, and does the penny trick apply only to the original tensioner or aftermarket ones as well

Thanks

Towsey

towsey956 said:

Ok so here we are again

I've got my self a gates belt at last from a local factors that's now selling them at £15

But I'm still keen to cure the actual problem before I fit this belt, so has anyone any info about this whole problem, and does the penny trick apply only to the original tensioner or aftermarket ones as well

Thanks

Towsey

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Have you had a look at the viscous fan pulley, I've seen them running slightly out of true when they have been warped due to abuse. Watch the grooves very closely and see if they move in and out when the pulley is turned.