I'm hoping someone can help me with this one as I've gone through a costly elimination exercise already !!!! When my car has been driven for about 10 or 15 minutes and the steering is on full lock there is quite a bad noise which is like the belt "Whipping" and squeeling. This noise doesn't occur when the car is cold. When I investigated this I could've sworn that the tensioner was causing the problem. Today I changed the whole tensioning unit ( Pulley, Damper, and Bracket ) and the belt. At first I thought everything was ok but to my dismay the noise re-appeared when the car was hot !!!! I don't really want to now change the power steering pump, viscous fan coupling, etc. without having a better idea of what it might be, hence asking for someones opinion on this forum. Any help would be greatly appreciated.

 

You probably have a bad accesory. Use a mechanics stethoscope to isolate the noise to a part; it will be the loudest when the scope is touched to the failed part.

 

Having searched the forums today some people have suggested it might be the alternator pulley which is supposed to "clutch" but if siezed can cause the belt to slip and the auto tensioner to vibrate. Does this sound sensible ? I would try it if I could get the pulley on its own but everywhere I try it's always the alternator complete !!!

 

The ac pully is the one with the clutch. Its a possibility.

 

it could easily the be the serpentine beltauto tensioner and you can see it twist when you rev and you will hear it, you can but the roller on its own which is the cheapest way and it just bolts on

 

I've already changed the auto tensioner and belt because I could see it vibrating when the steering was on full lock.

 

I went out and bought a new pulley for £60 but when I came to fit it I realised I didn't have the splined socket to the job !!! I did have a splined bit for the inner piece and so I thought I'd give it a go anyway. I was about to give up when I actually managed to free the existing pulley !!!! Happy Days. I've run the car for a few days and no more belt squeal or slippage. The pulley seems to be freewheeling when it should and so I returned the new one for a refund. Job done hopefully. Thanks for the help anyway. Cheers.