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I've been posting a lot trying to diagnose this loud squealing coming from my car when I accelerate (it stops when the car is idling or stopped, and when the roads are wet). First shop said they thought it was maybe something wrong with the AC condenser, even though the AC doesn't work but they don't feel comfortable working on AC so they sent sent me to another shop.
Second shop said the beast has a single pulley on it and a belt that is too big- hence the squealing. They also said this car SHOULD have a 2-pulley alternator on it, but that they didn't feel comfortable replacing the alternator so they're referring me to a third shop. I asked if they could put a smaller belt on the single-pulley or if I had to put the 2-pulley alternator on it. They said they didn't know. But they also said it SHOULD be just fine and safe to drive, just obnoxious.

So, can anyone help confirm- should it have one pulley or two? Can I just put a smaller belt on the one pulley? Is it safe to drive if the alternator belt is a little too big?

All of my wagons over the years had 2 groove pulleys.

Same here...alternator has always had two pulleys...at least on all the ones I have had

Hmmmm so at some point a PO put in a 1-pulley alternator. Any harm in keeping that there and finding a belt to fit?

Pretty sure the '84 TSM has a diagram of belt routing for all the Jeep models. Did you look at the TSM?

Foolishly don't know what TSM is. Anyway, pictures for what it's worth. Can I rock it like this and just get a better fitting belt? Or do I need the 2-pulley alternator?

Technical Service Manual, the factory manual for your Jeep. Most of '82 is online at http://www.oljeep.com and will be close for most things. You can get a CD-ROM version at RockAuto and other places, or printed copies are available. https://www.rockauto.com/en/moreinfo.ph ... 05&jsn=376

In your case, it looks like a DSPO (dip stick previous owner) replaced the alternator and did not switch over the pulley. You need a second belt to provide the traction needed for the AC compressor. Maybe you can find a source for an alternator with the proper pulley. Check junkyards if the parts store can't help (likely).

The belt width is right, but it's too long. The length adjustment on the alternator should be near the middle. Any parts store can sell you a shorter belt - that's easy. Either get the right part for your application, or have them measure the belt (they should have a device for that) and get one that's a couple inches shorter. Usually the length is printed on the belt, so it may be as easy as reading it. If you had a dual pulley, you'd buy a pair of belts from the same maker at the same time, so they will be the same length when installed and work together. This is very easy, trivial stuff for any competent mechanic. Does not reflect well on the places you went to.

The squealing means slipping. Slipping means heat. It will contribute to early belt failure. But driving it shouldn't be an issue. When you get a two groove pulley, replace both belts.

I would bet there are a bunch of people who have a spare pulley. Post up on WTB and I bet you will get a quick response.

tgreese wrote:In your case, it looks like a DSPO (dip stick previous owner) replaced the alternator and did not switch over the pulley. You need a second belt to provide the traction needed for the AC compressor. Maybe you can find a source for an alternator with the proper pulley. Check junkyards if the parts store can't help (likely).

The belt width is right, but it's too long. The length adjustment on the alternator should be near the middle. Any parts store can sell you a shorter belt - that's easy. Either get the right part for your application, or have them measure the belt (they should have a device for that) and get one that's a couple inches shorter. Usually the length is printed on the belt, so it may be as easy as reading it. If you had a dual pulley, you'd buy a pair of belts from the same maker at the same time, so they will be the same length when installed and work together. This is very easy, trivial stuff for any competent mechanic. Does not reflect well on the places you went to.

Awesome. I'm convinced that I need to go find the proper alternator, but am curious- you say the second belt provides traction to the AC compressor- does it serve an other purpose? What if I don't care about AC?

will e wrote:The squealing means slipping. Slipping means heat. It will contribute to early belt failure. But driving it shouldn't be an issue. When you get a two groove pulley, replace both belts.

I would bet there are a bunch of people who have a spare pulley. Post up on WTB and I bet you will get a quick response.

Thanks! You all and your acronyms- WTB?

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memsiej wrote:

tgreese wrote:In your case, it looks like a DSPO (dip stick previous owner) replaced the alternator and did not switch over the pulley. You need a second belt to provide the traction needed for the AC compressor. Maybe you can find a source for an alternator with the proper pulley. Check junkyards if the parts store can't help (likely).

The belt width is right, but it's too long. The length adjustment on the alternator should be near the middle. Any parts store can sell you a shorter belt - that's easy. Either get the right part for your application, or have them measure the belt (they should have a device for that) and get one that's a couple inches shorter. Usually the length is printed on the belt, so it may be as easy as reading it. If you had a dual pulley, you'd buy a pair of belts from the same maker at the same time, so they will be the same length when installed and work together. This is very easy, trivial stuff for any competent mechanic. Does not reflect well on the places you went to.

Awesome. I'm convinced that I need to go find the proper alternator, but am curious- you say the second belt provides traction to the AC compressor- does it serve an other purpose? What if I don't care about AC?

Likely you have the right alternator but the wrong pulley. If you can find a pulley, you can replace just that. If a shop would have replaced the alternator, they would have swapped the pulleys and sent back your core with the single-groove pulley.

With a properly tensioned belt, it should be fine as long as the AC is off. There is an electric clutch in the compressor hub that only turns the compressor when AC is on. Powering AC is a considerable drag on the belts. My two Jeeps w/o AC have a single belt.

Awesome, thanks. I have a lot to learn about this whole system (obviously) but so far I can't see the point in getting the second belt on there unless I"m trying to run AC which I don't care about.

Working AC will affect the resale value, should it come to that. Life happens.

The second belt isn't just for the AC compressor. The belt on the alternator has only a small contact patch. That's why it's squealing. It's slipping. The second belt gives you double the surface area contact patch so when you load the alternator or spin up the engine quickly, you don't get the belt slipping.

If you look at modern serpentine belt systems, you'll see the belt wrap around all the pulleys on the accessories, giving it a much bigger contact patch. There's a reason they do it that way.

Derf makes good points, but IMO the contact patch isn't all that small compared to other apps with one belt. If it's a problem, using a shorter belt, you can skip the AC pulley and get more contact. But I think it's going to be ok - looks to me like the belt adjustment on the alternator is way out on the end, and it can't be tightened enough not to squeal. I think the shop was right about this. How much can you deflect the belt?

tgreese wrote:Derf makes good points, but IMO the contact patch isn't all that small compared to other apps with one belt. If it's a problem, using a shorter belt, you can skip the AC pulley and get more contact. But I think it's going to be ok - looks to me like the belt adjustment on the alternator is way out on the end, and it can't be tightened enough not to squeal. I think the shop was right about this. How much can you deflect the belt?

You may be right. Though as you go up in amperage, the load on the belt increases. For a 63 amp alternator, I'm sure one belt is fine (even though I like to have more than one "just in case"). But go up above 100 amps and you really start to need that second belt.

agree w previous posts, but that alt belt looks too narrow, When my alternator gave up, the store did not have matching belts, so still running 1 belt, but no AC compressor for the last 6 year, it is a 75A, not an 85A as recommended w AC

letank wrote:agree w previous posts, but that alt belt looks too narrow, When my alternator gave up, the store did not have matching belts, so still running 1 belt, but no AC compressor for the last 6 year, it is a 75A, not an 85A as recommended w AC

Could be too narrow. That would make the belt sit down in the grooves and be effectively longer. There's a clear label on it - I think it's Gates - read the PN and check on RockAuto if it's what's spec'd for that app. Belt width varies by mfr and both width and length will be considered in matching a part to an app.