Revo13

I went to start up my 1998 Jeep Cherokee Sport one day and the belt was making a terrible squealing noise. After a few seconds of squealing the belt snapped. In the middle of replacing the belt I discovered that the alternator pulley was not turning at all. I purchased a re-manufactured one from an auto parts store, installed it, and installed the new serpentine belt. All was fine for about a week an a half. I drove it roughly 120 miles and all seemed fine. We got snow here recently and I went to turn on the rear defrost and the belt started squealing. Shortly after the battery gauge stopped working and the check gauges light came on. I shut the Jeep off and went to start it, started right up with no hesitation. The check gauges light was gone and the battery gauge went back to normal. Fast forward a couple days and the belt is back to squealing but I've picked out a pattern. When I first start the Jeep there isn't a squeal. I'll take off down the road and all seems fine, until I come to a stop. Once I come to a stop the battery gauge drops a few levels. When I accelerate the belt squeals. The more I accelerate the squeal stops and then the battery gauge returns to normal. 100% of the time when the battery gauge goes down I am stopped and idling and the belt squeals upon accelerating. But after reaching roughly 15-20mph the squealing stops. Another thing I noticed while stopped is when the battery gauge goes down I hear the blower fan slow down.

Sorry for then lengthy paragraph! I wanted to include as much detail as possible.

Gotyoulooking

Is it a new belt? New belts stretch out a little bit so needs adjustment after a couple miles put into it, even if its not just make sure to tighten enough.

Revo13

The belt is new. I thought that it might need tightened but the combination of other things made me think that it might be something else. Hopefully the snow stops and I can see if tightening the belt helps. How much deflection should the belt have? I've seen multiple people say 1/2" and others say tighten it all the way.

PatHenry

Everything you're describing is classic symptoms of a loose belt.

Edit - Your blower motor for the heat/a/c will slow if it's not getting enough amperage, so that's logical it would slow if the alternator isn't putting out enough juice.

If you don't have a belt tension measurement tool, you can grab the belt about 6 inches or so left (from standing in front of the Jeep) from the PS pump (right along the top between the PS pulley and idler) and twist it. It should not be "twist-able" more than 90 degrees. If it is, it's too loose.

It's certainly possible that there is something else wrong, but I'd tighten up the belt first. If you still get issues, take the belt off and check each pulley by hand to make sure they turn smoothly and without noise. It's common for the idler pulley to fail, but that's easy and cheap to replace.

Also, I have found that the Continental Elite (formerly "Goodyear Gatorback") belts are amazing and are a lot more forgiving than a standard belt. I had all kinds of belt squeal issues and belt noise on my previous Jeep (a TJ which used the spring loaded tensioner) and the Gatorback belt cured all of it.

Revo13

I'll check the belt tension when I get a chance. When I changed the belt all of the pulleys that should turn did, that's how I found the alternator issue.

Here is a link to the belt that I got:
Thanks for the info!

downs

The last belt I bought was from Napa and its napa branded but manuf by Gates which is well known belt and hose company. Just another option other than duralast or the like

fb97xj1

Check the pullies again by hand if you only turned them back and forth like some do. This includes the a/c clutch. It should spin free with no drag at all. Rust can build up behind it and make noise. Get in close and listen for any scraping and if any have any drag. Check for any wobble. If you see any black stuff on the tension pulley, clean it off. Rubber and dirt get burnished onto it and the belt could be sliding across it. Check the balancer for any signs of shifting front or back also, or any rubbing against the timing cover. It could even be the brand of belt. I used NAPA once, and it had some squeal when cold (it wasnt on a Jeep, tho). I have since used Goodyear/Continental or OEM belts and never had another issue. Not with the belts, atleast.

New belts for the XJ should be in the 180-200 ft-lb range, and 160 ft-lb or so with a used belt.

burningcabbage

so how much should the belt stretch? I'm replacing a belt with a water pump and the new belt that was a "direct fit" is like 4" shorter than the one coming out. Do I just need some bacon grease and a prybar or is this the wrong belt?

gat

You might be more benefitted by starting your own thread with you year and sub-model/engine. The power steering pump adjusts to accommodate some difference in length. Are you sure that your engine is the original to that vehicle?