2005 Scion xB with a really bad belt squeal.
 

Hi guys, i recently put a new water pump in my xB cuz the old one was leaking fluid. i also changed my belts. i kept getting a belt squeal when i use my a/c. it only did it when i used my a/c. i tried adjusting it to no avail. so i thought maybe i had a bad alternator belt. i replaced it today. now im getting the squeal with or without the ac being off. i dont know what im doing wrong. one of my buddies said maybe the ac compressor bearing was going out. if anyone has any advice id greatly appreciate it. i really dont want to take it to a shop. but cuz i live in Vegas i need my ac. thanks in advanced.

FWIK, it could be misaligned pulleys, bad tensioner, or pulley bearings. Try belt dressing just to see what happens.

Make sure the belt is tight...

You did loosen ALL the bolts for the compressor right? Cos your description doesn't sound like you did.

hi guys, thanks for advice. To james no i havent even touched the compressor let alone the bolts for it. im starting to think im not tightening belt enough. i let the car idle for a few minutes and looked at the belt. the power steering belt is moving but looks tight but when i look at the alternator belt it looks like its flapping around. i thought maybe my eyes were playing a trick on me cuz its spinning pretty fast. im gonna try and tighten it more and see if that does anything. when i adjust belt im doing it from the alternator and i only pull the alternator back by hand and then tighten bolts. ive read in a couple forums to use a screwdriver to pull alternator back so it seems most likely im not putting enough tension on belt. ive also read though that if u tighten it too much itll mess up the waterpump and i dont want to do that since i just replaced it. i wont use belt dressing cuz its a new belt and is not a long term solution.

In my experience, it was really hard to get the serpentine belt tight enough without an extra set of hands (one to pry the alternator into place, another to actually tighten it).

I think the belt dressing was suggested to help you narrow down your search for the noise

sounds like you just need to tighten your belt though

update guys, i got home from work this morning nd adjusted the belt. i got it as tight as i could. i took it for a test drive and it didnt squeel at all. my wife took it to work and she text me that it did chirp a little but thats it. i can live with a little chirping since thats what its done the last three years we've owned it. thanks guys for all the help