fan belt squeeling

[martin]

when on idle the fanbelt squeels how do i fix this

[insanitybeard]

It could be squealing because of several factors, firstly it could be because the sprung loaded tensioner itself is causing the squeal due to weakened spring tension, or it could be because the one way clutch pulley on the alternator isn't working as it should be- the best way to test the alternator pulley is to remove the alternator belt from the alternator pulley (the procedure for this is covered as part of this article) and spin the alternator pulley (fast) clockwise by hand, if you then quickly (not gradually) stop the pulley from turning, you should be able to see the rotor (the part you can see rotating within the alternator casting when you spin the pulley) carry on rotating briefly after you have stopped the pulley turning (i.e, it shouldn't come to a complete stop as soon as you stop the pulley rotating). If this pulley is defective it can be replaced without having to renew the complete alternator- GSF for example supply it, though be careful as there are a couple of choices of diameter I believe.

There may be other causes for the squealing, such as a air con compressor starting to seize or just a tired and worn out belt, or contamination on the belt/pulleys from an oil leak for example so it's worth looking at the belt and surrounding area/pulleys first before going too far and stripping things down.