Replacing Alternator Brushes

So I was at the crawl the other week, and when I was swapping some alternator brushes, several people had no idea what I was doing, or that it was even possible. Quick search on showed no decent threads about this, so I took some pictures when I was putting new brushes back into my spare alternator. This does NOT have to be done with the alternator removed, just as easy with it in the vehicle, and actually quicker than removing and replacing the alternator. If you don't want to carry a complete spare alternator, brush failure is probably 60% of offroad failures, and they're not large, heavy, or expensive to carry as a spare.

First of all, you're not going to find these at any normal parts store. I've found them at a few places online, and also at local starter/alternator rebuild shops. This is the correct brush set for a '99, not sure what other years use. Costs about $7-$13 depending on the source.



Tools required. I said it was simple! Phillips screwdriver, 10mm, and 8mm



Remove the cable, and the two nuts associated with it, and the plastic piece at the base just pulls out. (10mm). Disconnect the battery first if it's still in the jeep. Remove the 3 nuts and one little bolt on the back (8mm).



Picture with the back removed. If it's in the vehicle, the other connector doesn't even have to be removed for the back to come off. Undo the 3 Phillips screws holding the brushes in.



Worn out vs. new brushes. Sometimes, mud and dirt can make the springs stick, and they just need pushed in and out a few times to loosen them, there's nothing even wrong with the alternator.



If this is a garage repair and not a trail repair, polish the rotor with increasingly fine wet sandpaper to make the new brushes last longer.



Compress the new brush springs and slip it over the rotor, screw it in



Replace the back, and drive on!

Hope this was useful. Feel free to add details from other year's alternators if it's different.

Excellent! I took the brushes out of mine because I thought they were the problem (and they were) but I needed a working alternator before the alternator shop was open. I'd agree, easier to remove the alternator. Looks identical to 01 XJ brushes.

http://www.rakuten.com/prod/new-alt...hes-nippondenso-chrysler-dodge/256337604.html

That's the site I got this most recent set.

Its worth pointing out, that in some vehicles, like the German vehicles I used to wrench on, that its common practice to change brushes at least once before the entire alternator is considered needing replacement. This isn't some kind of cheapskate repair.

yet in the US, if the alternator quits working, 99.5% of people just replace the whole thing. Yup, not necessarily a cheapskate repair, just one that most people don't do or know about.

SC Rednek said:

yet in the US, if the alternator quits working, 99.5% of people just replace the whole thing. Yup, not necessarily a cheapskate repair, just one that most people don't do or know about.

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Tbh if mine went out id go to the local pick a part and get a new to me used one. But this was very insightful.

The alternator on my Ford Exploder had 300k+ miles and quit working. Couldn't replace the brushes because the armature was completely worn through.

SC Rednek said:

yet in the US, if the alternator quits working, 99.5% of people just replace the whole thing. Yup, not necessarily a cheapskate repair, just one that most people don't do or know about.

Click to expand...

That's because it's faster and cheaper to do that once you buy the first one with a lifetime warranty.

I had mine out in my 89 the last time it went out before the parts guy got it from the back and brought it to me.

This place has exact fit replacement parts for alternators and starters.

Awesome site! I got it bookmarked now. I think there was some confusion that I was saying it's easier to swap the entire alternator. On the contrary, it's only a couple minutes to swap brushes without removing the whole thing. And, if you play in the mud like I do, they really don't last very long, year or two at the most.

Not sure how old this is but I found a set are they pretty simple to change out? Looking at doing it tonight 5 bucks is a lot better than 100 haha

Nice thread to BRUSH up on DIY alternator repairs thanks :worship:

mnoeltne said:

This place has exact fit replacement parts for alternators and starters.

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This is where I buy all my alternator/starter parts too.

If you have a 91-98, the stupid terminal block with the two tiny studs for the field winding is on that site for like 7 bucks. I have a spare on hand now instead of having to run to the parts store for a $100 alternator when (not if) I snap the studs off trying to loosen the microscopic nuts. If it happens again I might just swap rear covers and terminal blocks + harness plugs for the 99-01 plugin style, because it's really obnoxious.