Alternator brush replacement (1 Viewer)

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Testing out my new ARB and Engo winch, the 80 got quite a bit of mud and sludge up in the engine compartment. About 10 miles down the road my charging light came on and I was getting around 9.5V while running. I suspected it got really wet and dirty and didn't think much of it except for kicking myself for not replacing the alternator or brushes during my HG job. Oh well. :meh:

I hosed out the engine compartment and let it dry for a day or two but never recovered. Picked up the brush kit PNC - 27370-75060.

The hardest part of the job is removing the alternator from the pivot bolt perch and fishing it out even with the power steering reservoir unbolted and moved out of the way. Otherwise there are 4-5 bolts to remove after deciding whether you're going to remove the battery box and P/S reservoir. 1 :banana: to 1.5 :banana: job and would recommend as preventative maintenance as others have suggested. Others may have different ways to perform this fix (on-vehicle, different cleaning method, etc), to each his own.....

#1 and #2 shows dirty alternator and OEM name plates.

#3 shows the fasteners you need to remove to remove the cover. There are a total 3 nuts and one bolt you need to remove in order to remove the cover. You will also want to remove the bottom most 'generator wire nut' and black shroud at top right in order to remove cover.
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#4 shows shows area you can use with screwdriver to help pry up the cover. Mine was pretty stubborn.

#5 - with the cover removed you will see my dirty innards. Red arrows show the two screws are to remove the brush assembly.

#6 - close up of my worn brush assembly.
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#7 - PNC 27370-75060 "Hecho en Japan", my favorite!

#8 - New, clean brush assembly. You will notice that the fastener tab heights are not symmetrical so be sure to watch how the old one comes out and orient accordingly.

#9 - Clean alternator (degreaser, nylon brush, rags, water bottle mister, blew out with air compressor) ready for cover and final installation.

After placing some dielectric grease on my connections and installing/adjusting belts I have 14V at the alternator and 12.9V at the battery at rest/engine off. Road test has been good so far. Hopefully the fix lasts a long time......

:beer:
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Dan it, just placed a order of junk from toyota yesterday and forgot to get this. Good job man!!
 
80 got quite a bit of mud and sludge up in the engine compartment. About 10 miles down the road my charging light came on and I was getting around 9.5V while running.

See why Woody hates mud?

You can get a coating of mud between the brushes and slip rings, preventing contact. To avoid getting stuck out on the trail if this happens, hose down the alternator with fresh water while it is running and this will usually clean it out. Mud can get into everything and the same approach can often fix things, even clutches that have lost friction after getting mud into them. Wash out the mud and go.
 
Did you have a belly/splash pan attached?
 
Did you have a belly/splash pan attached?

Nope - PO lost that among other things. I think that might be a good investment and will start checking the classifieds
 
thread resurrection: wanted to add to this great write-up on brush replacement. The brushes are usually the culprit and as more higher mileage trucks are driving around this will probably come up.
you can also replace the brushes while on the truck in a pinch as follows.

- remove the 4 screws/bolts that holds the cover on and just loosen the "generator wire nut" to get the cover off. (see above)
slide the cover off and twist it over the connector - no need to disconnect the connector wire as you will have enough room when its out of the way.
- remove the oil filter - this will give you so much more room to leverage the screws that hold the brushes in place without stripping them. you can even fit a smaller electric impact screwdriver in there, worth it especially in the rust belt where the older stubborn screws can give you a headache. I did this on one without removing the oil filter and stripped one of the screws, the lower one. I then had to remove the whole alternator to get it done. On the other when removing the oil filter first it was a non issue with the impact.
- optional - remove the three bolts that hold the ps reservoir allows you the push it out of the way to get in there more if needed.

- remove the 2 screws that hold the brushes, attach new brushes and button everything back up.

you are now able to get back on the road/trail
hope this helps somebody!
 
thread resurrection: wanted to add to this great write-up on brush replacement. The brushes are usually the culprit and as more higher mileage trucks are driving around this will probably come up.
you can also replace the brushes while on the truck in a pinch as follows.

- remove the 4 screws/bolts that holds the cover on and just loosen the "generator wire nut" to get the cover off. (see above)
slide the cover off and twist it over the connector - no need to disconnect the connector wire as you will have enough room when its out of the way.
- remove the oil filter - this will give you so much more room to leverage the screws that hold the brushes in place without stripping them. you can even fit a smaller electric impact screwdriver in there, worth it especially in the rust belt where the older stubborn screws can give you a headache. I did this on one without removing the oil filter and stripped one of the screws, the lower one. I then had to remove the whole alternator to get it done. On the other when removing the oil filter first it was a non issue with the impact.
- optional - remove the three bolts that hold the ps reservoir allows you the push it out of the way to get in there more if needed.

- remove the 2 screws that hold the brushes, attach new brushes and button everything back up.

you are now able to get back on the road/trail
hope this helps somebody!

AWESOME! This thread and instructions how to replace the alternator brushes was perfect and saved a bunch of time! I was going to purchase a rebuilt alternator, but thought it was worth $25 to try the brushes only and everything is good again. Plus I will "wash" the alternator while running after mud adventures. Thanks for the help!
 
Just followed same procedure with my 97 in Norway at campsite with replacement of bushing. Back up charging.
Happy days. Off to sweden finland then St.Petersburg abd back around to Estonia Latvia Lithuania Poland Germany Netherlands back via ferry to UK and back to Ireland
 
I don’t advocate washing out your alternator routinely after mud events. Only do it in an emergency if your alternator stops working after a mud immersion.
 
#7 - PNC 27370-75060 "Hecho en Japan", my favorite!

#8 - New, clean brush assembly. You will notice that the fastener tab heights are not symmetrical so be sure to watch how the old one comes out and orient accordingly.

#9 - Clean alternator (degreaser, nylon brush, rags, water bottle mister, blew out with air compressor) ready for cover and final installation.

After placing some dielectric grease on my connections and installing/adjusting belts I have 14V at the alternator and 12.9V at the battery at rest/engine off. Road test has been good so far. Hopefully the fix lasts a long time......

:beer:
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Thanks for the part number
 
Thanks for the write-up. I just replaced alternator brushes on the 80. I did not pull the alternator. This is a 1 🍌 job. My old brushes have 104,000 miles on them. Still good for a while but nice peace of mind for $15 and an hour. Tip of screwdriver shows location. As written above, pull the oil filer and remove PS reservoir bracket bolts and there is plenty of access. 8MM socket is needed for the cover nuts. My connector did not break but I could not get it to click back on so it will be getting replaced.
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