96 Cherokee 4.0L squeals like a **** when I turn the AC on. I thought I had a bad serpentine belt, so I put in a nice gator belt yesterday. Then I realized that a lot of the noise was coming from what seems to be the idler pulley (even though I replaced it about 6 months ago)

So I bought a replacement pulley. The bearing in the replacement moves a bit better... but I noticed that the old one has a metal spacer that sits against the bearing that the new one didn't come with. I used the old spacer, which is kind of cruddy, and it STILL squealed a little when I first started up with the new pulley installed. It squeals a LOT when the AC is turned on.

So, I pulled it back out and I'm about to polish and grease the spacer. But I can't help but wonder if I'm doing something else wrong.

The belt seems fairly tight, not a whole lot of play on the longest run. And after I get that pulley tension adjuster dialed in to pull the belt tight, I cranked the center bolt in the pulley down pretty tight to keep it in place. I can't find torque specs.

Is any of this wrong? Should I be leaving the pulley's center bolt more loose? Should I not be polishing/greasing this pulley spacer? Am I looking in the wrong place entirely?

Thanks for any help you can give I don't really know what I'm doing.

 

I was having the same problem on my 98 after I put in a new motor. Tightened the belt added a little belt dressing and now it's gone.

 

Yeah, I think you're right on the money. I thought it was a good tension but the polishing didn't make much of a difference, so I started screwing around with the tension bolt while it was running.

Turns out it needed to be a good bit tighter than I thought. I cranked the tension bolt down and it stopped squealing.

Reading the other threads here, I think they're right when they say about half an inch play in between the power steering and water pump. If you can get any more than that out of it it seems to make the pulley of all things squeal.

 

Hmm, I'll have to go out and tighten mine up tomorrow. She's been squeeking for awhile now when I first turn the AC/Defrost on.

 

Wow. that simple. i just did the idler pulley on my 2000 xj and had the same squeak. tightened up the belt and it stopped. very helpful!!!!!

 

you can use dried soap on belt to stop noise. an oldschool trick from my grandpa.