Could be either one OR both. A bad belt can squeal, a bad bearing in any of the belt driven components could be causing a squeal. OR a bad bearing in an idler may have caused the nelt to glaze and you have both problems.
Easy way to tell is to remove the belt, start the engine for a bit and see if the noise is gone. Don't let it dun a long time but you should notice the lack of noise withing 10 -20 seconds anyway.
If the noise is gone then rotate all the different parts turned by the belt. If one doesn't turn OR turns with a squeak or scrape then you probably have a bad bearing. You may have to feel for the bad bearing as well, a bearing should turn smooth and with very little drag. A bad bearing can show up as a rough turning bearing as well. That will not feel smooth.
It could also be that the tensioner spring is failing. The only way to repair that is to replace the tensioner.
Belts can be a VERY BIG PIA. In more ways than one.
Sunday, June 21st, 2009 AT 3:25 PM