squeaky fan belt but not s50

[yetti24]

any ideas on this i am at the end of my tether with it, the fan belt squeaks but only when the coolant system is filled up, if not it does not squeak, i have changed the belt, all the pulleys, power steering pump and the water pump but it still squeaks, if i spray wd40 onto the belt it stops for 30 seconds then starts squeaking again , i even tried taking the adjuster pulley out in case the belt was to tight, could it be something to do with the coolant system ? if i drive the car for a few miles it also stops squeaking but once the car has cooled down it starts squeaking again, any ideas greatly appreciated

[UweM3]

I used something called "belt dressing". It's an aerosol can. don't know where to get it, got it from Jake when he went back to live in the states. Makes the belt a little sticky. Never squeaked again.

[d6dph]

http://www.wilcodirect.co.uk/index.php? ... ts_id=1955

[Speedtouch]

Or you could try hairspray: the BMX Freestylers used it on their tyres back in the day to make them stick to the ramps better

[DanThe]

What type of tensioner do you have? The coil spring type is the best, the one that looks like a damper often weakens and causes belt slippage

[yetti24]

i have tried the hycote belt slip stuff does not work, wd40 works but it starts squeaking after 20 seconds of spraying it, tried another new belt and that hasnt worked, the tensioner on my car is an offset pulley with the bolt that goes through, it only fixes in one place as it has a small lug on it, the belts seems really with tensioner on but i have tried it without the tensioner and it still squeaks, i have also tried running the car with no thermostat in case there was a water flow problem as it only squeaks when there is water in the coolant system

[HenryM3]

Had the same sort of problem a few months ago, renewed the same bits with no joy. Now I don't know what car you have fitted the engine to but if it's an M3 look at the undertray and make sure it isn't rubbing on the sump. I know it sounds stupid but I had convinced myself it was all sorts of different things, spent loads of money, then 10 seconds with a stanley knife cured it.