Questions questions questions....here goes. My 92 4.0 wrangler squeels and screeches so loud its embarassing. The belt is in decent shape and I think its tight enough (i dont want to make it too loose). I tried squirting LPS lube behind each pulley at a time and then starting the car to see which one getts rid of the noise. Unfortunately I couldnt get into some areas. Doing it with the car running just blew the spray away. It somewhat quieted down when I got some by the water pump pulley or possibly onto the belt itself. I really dont want to expeirment by changing the water pump. I was thinking of rigging and induction motor to each individual pulley to see which it is but that seems like a ton of work. Any other way of checking what this is??
Its loud even as I'm driving and at a red light everyone looks at me. <img src="/forums/images/graemlins/scared.gif" alt="" />

Squealing belts usually indicate a missalignment of one or more pullys. I would use a long rod and while idleing put the rod on each belt driven item to make sure it wasn't a bearing going south.
The most common squeal on that engine would be one of the idler pullys. Them things have rollerskate bearings in them and are known to be the weak link in the single belt systems. Take the belt off and examine them for wobble or possible FELT grinding in the bearing. If there is over 80,000 miles on the idlers I'd just replace them anyway.
Big Jim

Thanks Big Jim. i have 150K. i'll try the new idler pulleys, check other pulleys for slop and alignment while the belt is off.

I bought a HO alternator for my project and experienced alot of squealing from the V belt. Wrote the distrubutor and he suggested replacing the belts and REALLY tightening it up. Since the belts were new, I just tigtened it further and it eliminated the squeal. Since yours is a single belt system with tensioners, I would think that the tensioner would be the culprit like Jim said. If you dont find a bad bearing, replace the tensioner and hopefully that will add the pressure you need to end the squealing. Jeep had a problem with A/C compressors kicking in and squealing so check that if its so equipped. Maybe your compressor clutch is going bad. <img src="/forums/images/graemlins/notooth.gif" alt="" />

Had the same problem. But only after I killed the battery because ofleaving the lights on. Boosted the the old sow and the squeel started, no doubt the draw on the battery was making the alt work hard. After a bit of driving the squeel would not go away. WTF I changed thebelt and like a previous response I "reefed" the belt tight and no squeel. I'll probably have to tighten the belt some more because of stretch. 10,000 later no squeel and no belt adjustment yet.