voltage light on dash on - is my alt toast?

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couple more pics showing the gunk buildup.

I also replaced the AC idler pulley bearing while i had the belts off.
Alternator cancer 007 (Medium).webp
Alternator cancer 010 (Medium).webp
Alternator cancer 005 (Medium).webp
 
OK, cleaned it up really well. Put new brushes in and re-installed with new belts. Scangauge says i'm charging at 14.6 volts. That is at idle. Sounds about right, and the dash light is off!

The biggest pain is just getting to the Alternator. The battery box has to come out along with the battery. The PS reservoir has to be moved also.
 
Nice work, 14.6 is great, your original alternator with new brushes is cheaper and more reliable than a parts store alternator. it can be done without removing the battery box, you just unbolt the PS reservoir and slide the alternator out the back, first time I did it with the battery box removed good to see how everything fits together, try it the other way if you ever need to do it again.

:beer:
 
Look it at the brighter side, you will able to upgrade it to the 130 amp alt in a breeze and with your eyes closed since you practiced with the OEM :D
 
honestly, after you get the alternator out, putting new brushes in is super easy. Everyone should do it, just the same as if they were going to put new contacts in their starters.

Raven, I honestly don't think i could have gotten the alt. in or out with the battery box in place. THe hing for the starter and it's bolt are a very tight squeeze. I had to use a brass drift to get that fit lined back up so i could insert the bolt. With the battery box in place i couldn't have gotten the angle to tap that thing in place. Also, taking the adjuster bolts out are a breeze with the box out. With it in, those things are a pain.

The box only takes a few seconds to get out.
 
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concretejungle said:
honestly, after you get the alternator out, putting new brushes in is super easy. Everyone should do it, just the same as if they were going to put new contacts in their starters.

Raven, I honestly don't think i could have gotten the alt. in or out with the battery box in place. THe hing for the starter and it's bolt are a very tight squeeze. I had to use a brass drift to get that fit lined back up so i could insert the bolt. With the battery box in place i couldn't have gotten the angle to tap that thing in place. Also, taking the adjuster bolts out are a breeze with the box out. With it in, those things are a pain.

The box only takes a few seconds to get out.
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I managed to do it in the past with the OEM small case Denso without removing the battery box but it's impossible when dealing with the larger 130-150 amp case. There is no way to remove or install it without ALL the steps you did. Anyhow I agree with you, I will never remove again another one with the battery box in place. May be the japanese mechanics have smaller hands and can do it with a tweezer but I can't.
 
well, damnit!!! I drove around for 2 days now with great voltage. Got half way to work this morning and the light came on the dash! Looked down at the scangauge and i was showing 12 volts!! WTF! I guess i should have dug deeper into the alt.

I guess i will go ahead and upgrade to the higher output starter. their is one close by for $75 for a 130 amp unit.
 
If you find you need a voltage regulator, I've got one that I bought at NAPA. Ended up not using it but they wouldn't accept a return on an electrical part. PM me if you need it. Also, how much work and $ do you want to put into new alternator, etc. before fixing the leak that caused the problem in the first place?
David
 
hmmmm... we are talking about the same internal voltage regulator right? Inside the alternator? I normally would run a toyota part since it has lasted this long, but right now i have a NAPA about 5 miles down the road.

I'm in a sticky situation here. I need to get this truck back on the road as quickly and cheaply as i can for at least 14 more days. After that i can park it and do what needs to be done.

Had a monkey wrench thrown in the mix...drove 40 miles to the junk yard to get the 130 amp alternator and there was a paper taped to the door saying closed for holiday. Open in a week!! WTF!
 
Well, as per Cdan's suggestion i took the alternator to autozone to have it tested. Failed!

Dang.

also, the voltage regulator is a servicable part. Dan doesn't "usually" have one in stock and it's cost, even smart shoppers, is too high compared to a fully remaned unit for not much more.

I guess i am forced to let her sit until after the salvage yard guys come back from their 4th of July vacation. :o:meh:
 
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I sure don't like to encourage this but if you don't run much at night and go light on the accessories you might be able to just put it on a battery charger overnight every night. Maybe even at work??? A pain in the posterior but might limp you through.

Bill
 
Photoman said:
I sure don't like to encourage this but if you don't run much at night and go light on the accessories you might be able to just put it on a battery charger overnight every night. Maybe even at work??? A pain in the posterior but might limp you through.

Bill
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Thanks for the suggestion. I had thought about that, but i don't want to ruin the less than 1 year old yellow top optima i have. That would be a extra pain. :bang:
 
Sorry-wrong voltage regulator. :frown: I feel your pain. Good luck on getting 'er back up and running.
 
All,

Has been a long time since I have posted but thank you for this thread and forum on the FJ80. My 1996 LX450 with ~300,000 miles which I have primarily been using around the neighborhood and my land and some remote property close by all of a sudden had a red light with no words or picture above the voltage meter (top right side of gauge cluster). I ordered the part number in this forum and removed the alternator/generator and opened it up an sure enough the brush had reached the end of its life. Cleaned everything up, installed new brush, and then proceeded to put it all back together again. I found the removal real easy and the put back together tough as I couldn't get the tensioner bolts lined up and it is pretty tight in there with my big mitts. But with a little persistence it all went back together again and it's working awesome and the light is off.

Thanks everyone.
 
Ok, I lie the red light just came back on. Testing the voltage at the battery I have 12.64 volts, with the truck at idle the voltage is 12.40, at 2500 RPM the voltage is 12.40. My father was driving the truck after the red light came on (I asked him not too!) and it died on him when the battery died. I picked up a new Brush from the dealer and got that installed and could tell the old one was at the end of its life. Sort of like an old wooden pencil with no more eraser above the metal sides. Still some there but just no longer usable.

So any suggestions as to what is going on? Could I have installed something wrong on the alternator? Seems from everything I read these alternators are pretty much lifetime units except for the brush and the regulator and if that goes might as well get a re-manufactured alternator due to cost. However I am not seeing any varied voltage so I think the regulator is fine.

I did take a trip with my kids and father today of approx 75 miles with multiple stops and restarts and the truck performed great. The voltage meter on the dash was above the mid line where yesterday with red light on before brush replacement it wouldn't come off center.

Would appreciate the groups knowledge and ideas on this one. Thanks everyone.
 
FYI i had an experience a few years ago with the battery not charging properly. It ended up being a set of worn out belts that had stretched. After tightening them, the alternator started charging correctly. I ended up replacing them and then re-tightening them after a few months and all is well.

My original problem was the alternator which i did replace. I haven't had an issue since.
 
I gotcha, I just took my original to get rebuilt I had a high output in its replace and it didn't last long. I run 3 sets of lights and was wondering if it's straining the alternator to much so we will see what the original denso can do. Thanks for the reply
 
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