I can't seem to get rid of a very annoying belt squeak on my GLH Turbo.
It has an '85 TI engine, but uses an '89 water pump and 90 amp Nippondenso alternator. The water pump uses a smooth pulley and the associated '89+ belt routing. All of the pulleys appear to line up nicely. I adjusted the sleeve in the alternator pivot to get it just right. The accessory bracket has been fitted with poly bushings from PolyBushings.com. I thought maybe the belt was a little loose, so I tightened it and nothing changed. It is more of a constant squeak/chatter as the revs rise than the typical screech you would hear with a loose belt slipping.
I tried using some Prestone belt dressing (spray can), and it helped a little bit but not much. It doesn't squeak much at idle, but as the revs increase it gets worse.
Should I just try a new belt? The belt is older and just something I had lying around. Not sure what else to do at this point.