CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

Installing alternator in 82 CJ7?

How to install alternator in 82 Jeep CJ7 w/serpentine belt?

I don’t think a 82 jeep had a serpentine belt, they had multiple “v” belts. Do you have one belt or a few belts??

Have you run into some unusual problem with removing the alternator, MoMo2? The mounting of an alternator on CJs was pretty straight forward.

It’s not Stock… One serpentine belt. The problem is one person removed the alternator & another is now trying to install it. Were not sure we have all the brackets. If we could just see a picture, diagram or under the hood of another we could install it no problem. Can anyone help me with that?

If it’s not stock, you are going to have a problem with that. A google search of images might be your best bet.

If a single serpentine belt turns everything look at newer Jeeps to find when that setup was first used and get a printout of the belt routing from any McParts store.

Hold on… I just looked up the 82 CJ-7 at Auto Zone and there was a single serpentine belt on that engine. Depending on options belts from 88 to 90.5 inches were used.

Which engine is this? Could be a 4 banger, most likely it’s the 258 I-6, but could also be a 304 V8…or could be any number of aftermarket swaps. The alternator’s mounted differently in each of the above, and it’s no help to show a picture without knowing which engine. But, all options revolve around the same principle. You’ll have two mounting holes on the alt, one will allow the alt to pivot, and the other will slide along an adjuster to tension the belt. And yeah, the 258 probably had one serpentine belt from the factory. You can rebuild that Jeep 5 times over from recyclers and Jeep specialists, so you can probably very easily find an entire assembly pretty reasonably. Other than that, you can probably manipulate a universal mount to get it to work.

Jeeps had a reputation of using parts from where ever they could get them…Does this one have a Motorola alternator? Delco? Motorcraft? you never know what you may find…Same thing with the ignition systems they used…

Its a 258 I-6. Its a Delco alternator. When bolting the back of the alternator to the bracket, the pulleys don’t line up. Could it be the brackets bent on the backside, causing it not to line up? I’m not talking about the mounting brackets, I’m talking about the bracket in back that the alternator bolts to.

hmm, I’m a little confused by what you mean when you talk about bolting to the back of the alternator…there only should be mounting points on the front (pulley) side of the alternator. However, if this isn’t a stock setup, maybe someone jury rigged some oddball mount?

Maybe the info and pics in this link would help? http://www.jeepforum.com/forum/f8/alternator-mounting-bracket-889658/

That’s what I’m thinking. I don’t think it is stock & that’s why I’m having such a hard time lining it up.

It has a place to bolt in the back, but I don’t think it was before. So if I put it back in without trying to bolt it in the back I think it will work. I’ll find out in just a few.
Thank you & everyone else for your help. Much appreciated.

Good luck! Let us know how it goes.

If the front mounting holes are opposite to each other there should be no need for other bracing.

I just got an update on this Jeep. It appears the motor has been changed & that I should be looking for an Alternator for an 84-85 CJ7 258 I-6 4.2 with Serpentine Belt, No Air conditioning but with Power Steering?

The new alternator is 85 Amps. The starter is 65 Amps. Is that going to be a problem? Also, is 85 Amps to much for my Jeep?

No… I run one thats 145 amps. 1991 Jeep Wangler 4.0L 6 CYL high output.

Are the Alternator’s the same size for an 84 or 85 258 6 cyl. Motor? The bottom bracket won’t fit. We’ve already been thru an Alternator that was too big., when we thought the motor was for an 82. Now we think the alternator is too small. ??? Is this the 3 bear’s story? lol…

Jeep stands for “just everyone else’s parts” it’s not uncommon for parts to change year by year especially jeeps of that vintage.