Fan belt squeal

[shrek37]

Hello all, My 1999 w210 3ltr diesel auto has a massively annoying squeal since I fitted a new non genuine fan belt. I fitted another one yesterday and the squeal has returned today. from cold it squeals for around 5 minutes then is ok all day until cold again. I have checked the alternator and water pump etc for play or bearing noise and nothing. it sounds like alternator side but nothing seems to help. any idea's before I crack up.
cherrs

Ash.

 

[television]

I would have said that it is not tight enough

 

[delboy777]

I would have said that it is not tight enough

I would agree with Malcolm

 

[shrek37]

belt

its as tight as it goes as its a spring loaded tensioner and it feels as tight as it should be, I could be wrong, is there another way to tension the belt other than the sprung loaded one.

Cheers

Ash

 

[television]

When starting from cold the alternator is running at full power to charge the battery, you could try and de glaze the pulleys, and that should help. Is this second belt an original

 

[meanie]

Check the pivot bush for the tensioner arm.They wear out & so you don't get the tension that you need because it binds uo.

 

[wireman]

I thing meanie may be onto some thing, the pivot on my 250d was a ball race which had seen much better days and I had similar belt noise problems. The associated small damper could be shot at as well.