Alternator failure....or just about

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94SRUNNER

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Toyotapartsdeal.com

It looks like you have a 99', which means you have the 100A alternator. You may know this but you can get the voltage regulator for ~$88 from Partsouq.com and in my experience their shipping is faster than Toyotapartsdeal.com

Its frustrating that the OEM voltage regulator for the 130A alternator is no longer available. :(
 
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It looks like you have a 99', which means you have the 100A alternator. You may know this but you can get the voltage regulator for ~$88 from Partsouq.com and in my experience their shipping is faster than Toyotapartsdeal.com

Its frustrating that the OEM voltage regulator for the 130A alternator is no longer available. :(

I did not know that thanks for the info. I'm going to pull the alternator and inspect it. I've ordered the brushes so I'll try that first. Thankfully I have another car to drive so if the brushes don't fix it or the bearings are bad I can replace those next
 
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Might not be a horrible idea to change the accessory belt tensioner at the same time. I did mine together with the alternator and power steering pump, as I recall, it made a lot of sense to do them concurrently.
 

JunkCrzr89

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Might not be a horrible idea to change the accessory belt tensioner at the same time. I did mine together with the alternator and power steering pump, as I recall, it made a lot of sense to do them concurrently.
Agree
 
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Might not be a horrible idea to change the accessory belt tensioner at the same time. I did mine together with the alternator and power steering pump, as I recall, it made a lot of sense to do them concurrently.

Excellent suggestion, since you'll be right there. Pain to do it later. 👍
 
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Got this SOB out finally. Bearing could probably use replacement but doesn't seem too bad. Fairly clean inside, regulator looks ok, not melted or dirty.

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94SRUNNER

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JunkCrzr89

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Have you reached out to a local alternator shop (B & M Starter & Alternator Services is in Pensacola) to see about a rebuild?

I haven't but I will definitely keep them in mind when this one craps out again.

That rotor shaft looks to be about toast. New brushes may not keep it going for very long...

I guess I'll see how long I can get and then just send it off for a full rebuild unless I can source those parts myself. I imagine you can't get them from Toyota?

EDIT- Nippondenso internal fan alternator slip ring for Chrysler, Honda, Suzuki, Toyota - 7190904 is that what I need?
 

jerryb

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I was gonna say, look at those ridges!
at least these ones look easier to replace than the 130amp ones. Alternator 100 Amp 1998-2002 LX470 Land Cruiser 4.7L (101211-7860, -7861) - 13856
BUt look at the rotor, it's 49$ that's cheap plus it comes with new rings and bearing. Rotor (Armature) Denso Alternators 12 Volt, 100-125 Amp, 6.1" / 155mm L - 7090655

Ah yeah that's a good point. I will definitely go this route next. For $50 it's worth it to just do that whole assembly. I assume I wouldn't need a press to get that back on right?

I figure I got 187k miles out of this setup so far, if some new brushes get me another 20k before I have to wrestle that thing back out I'll be OK with that. I put about 5k to 7k /year on the truck now.
 

jerryb

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id call and ask them, those guys show rotors with the bearing on that one and without the bearing on the 130amp. Both have new rings though. I'd definitely try to keep an original OEM alt up to speed with decent parts, even if you switched to a rebuild numbered toyota/denso. While fixing the original.

I imagine once one of the brushes starts touching the black plastic under the copper the voltage will just start dropping. There is a spec for it in the book. 14mm comes to mind. not sure.

I was glad I had a second one sitting around. They have gone up in price recently, the 130Amps. I bet the 100amp alt R's are cheaper.

There is one decent thread on club lexus- I think it was- that went through slip ring redo, it had great pics.
 
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id call and ask them, those guys show rotors with the bearing on that one and without the bearing on the 130amp. Both have new rings though. I'd definitely try to keep an original OEM alt up to speed with decent parts, even if you switched to a rebuild numbered toyota/denso. While fixing the original.

I imagine once one of the brushes starts touching the black plastic under the copper the voltage will just start dropping. There is a spec for it in the book. 14mm comes to mind. not sure.

I was glad I had a second one sitting around. They have gone up in price recently, the 130Amps. I bet the 100amp alt R's are cheaper.

There is one decent thread on club lexus- I think it was- that went through slip ring redo, it had great pics.

I actually found that thread on Club Lexus. not sure I want to go that deep if I can just replace the whole rotor assembly for $50.

The FSM says minimum thickness for the slip ring is 12.8mm, also says replace if scored.....I guess this brush replacement will be an experiment to see what you can get with just brushes at this stage. How did those grooves get that bad anyway? I've seen some pictures of guys with over 200k miles and their rings look new
Capture.PNG
 
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Just test drove and no obvious issues. I'm not sure if this is indicative of anything as I have never watched the volt meter this close. When I turn the lights on and off the meter ticks down a hair for a split second then goes back to the 3/4 line. It does this each time I turn the lights on and then off....very slight movement but it's there. Anyone else seen that under normal conditions?

I turned both seat heaters and A/C front and rear on but there was no movement in the gauge.
 
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How did those grooves get that bad anyway? I've seen some pictures of guys with over 200k miles and their rings look new

Small bits of sand/grit get under the brushes. Especially when wet, it makes a slurry. When the brushes are worn down and the spring pressure decreases, when you start the engine or rev it....the brushes 'bounce' a little allowing crud to get underneath them.

Alternator is not in the best spot when think about it. Starter either....if you ask me.
 
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Where do your volt meters sit? I've noticed mine dip just a hair below the 3/4 line every once in a while at idle since brush replacement, and I'm not sure if this is normal and I'm just watching the gauge more intently now.
 
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Where do your volt meters sit? I've noticed mine dip just a hair below the 3/4 line every once in a while at idle since brush replacement, and I'm not sure if this is normal and I'm just watching the gauge more intently now.


Just right.

lex22.JPG
 

94SRUNNER

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Mine sits right at or just below the 14V mark on the factory gauge. My ScanGauge reads anywhere from 12.8-13.9V depending on load. I also have a voltmeter in my USB charger and the reads a consistent 0.2-0.3V higher than my ScanGauge.
 
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@thebeedeegee so what did u end up replacing on the alternator? just the bushings or the whole kit? i.e. bushings, bearings, regulator, seals etc? and from where did u get it?
 

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