On my '00 Runner I have noticed that at idle with heater on, rear defroster on, wipers on, etc, the battery voltage will drop from 13.6 down to 12 volts (sometimes even lower). If I engage the A/C, the rpms usually rise enough to boost the dropping volatge. I replaced the OEM battery and much the same symptoms other than before it would drop down to low 11's.

If I bring engine speed up by a couple of hundred rpm over idle, say to 850 - 900 rpm, the altenator brings the voltage right up to more than 13.5 volts. Do you think that my alternator is on its way out? The engine is a 3.4L V6. Never any other propblems like starting etc. even in real cold weather.

I searched the net for remanufactured units. Anyone have any experience with eBay remans? Found voltage regulators but they are more expensive than a remanufactured alternator!

I think the stocker is an 80 amp unit. I am basically stock on electrical load. Any opinions on going to an upgraded reman to say 120 to 130 amps?

Thanks

 

Don't replace the alternator, just put in new brushes

http://www.4x4wire.com/toyota/mainte...nator_brushes/


Aftermarket are junkl. Nothing better than the stock denso alternator.

 

Thats only about a volt and a half drop. Not bad for running all those accesorries at idle. I really wouldnt worry about it. Your car isnt made to sit at an idle with everything on anyways. I think your charging sys is working fine. Your battery will go before your alt will. When your alt does stop charging, get a set of brushes for it. Or if you are that worried, buy a denso reman

 

Alternators optimal output is around the 2000rpm range.At Idle it really doesnt charge. Your system seems fine, just make sure you have a good battery, because a bad one WILL take out your alternator.

 

haha, if you think that's a voltage drop, you should've saw my voltmeter dive down when i had my system and before putting a power cell in it...but all kidding aside, it sounds like you're alright, but the upgrade definitely can't hurt ya...

 

X2

Your system is working normally.

 

Thanks everyone for your input! I will order a set of brushes and pop the alternator out and check the old brushes out once the weather warms up (hopefully in a month or so). That's the problem with digital gauges, sometimes they make you worry for nothing.
Vic

 

Let me know what you find for a price for the brushes. I have a bunch of them that im selling and want to know whats fair

 

If you have a set that will fit an '00 with a 3.4L and Denso alternator, I would be interested in a set. Pricing less than the stealer would be good. Haven't had a chance to look into it yet and may not do so until the warm weather arrives.

 

ok. I do have a set if ya want it. I will see what the dealer charges tomorrow and I will beat their price. I will let you know tomorrow then.

 

Mine does the exact same thing down to about 11.7 at the lowest with everything on. Everything is totally ok.

 

Yep, but I bet if you rev the engine a bit, the voltage will pop right back up to 14V +
Like you said, totally normal.

 

how long does a job like replacing the bushes take usually? doesnt look that hard even for rookies like myself

 

maybe an hour. Depending on how familiar you are with your eng. You only need to remove the back cover of the alt to get to the brushes so its pretty easy

 

dang and that will save atleast a 100 bucks too.. can anyone really verify that this is worth the effort? meaning that it wont go bad pre maturaly bc the rest of the alt is older than the part being replaced.. hope that made sense

 

Yes, the brushes usually wear out first, but there's no guarantee on the rest (bearings, regulator, etc).
Alternators are more in the "if it ain't broke, don't fix it" category......if you'r charging at 14+ volts at 2500 RPM, leave it alone!

 

understood.. but its nice to know your options when it comes time to replace the whole thing or just the brushes

 

Sorry Mike I got a bit carried away with my soapbox......just didn't want you to think this was a preventative maintenance type of thing.

 

i agreed with you to begin with jamie. i normally wait till its shot before replacing. i just had no idea it can be fixed for 30$ or less

 

ok. sorry I havent gotten back to you sooner. I called the stealer and they wanted $23 for the brushes and they had to order them. DUMB. I will sell you a set of alt brushes, delivered to you for $20