sleestak240

Hey all,
It seems the charging system on my '87 4Runner (22R-E) is acting up, or at least the voltmeter indicates it. I'm somewhat suspicious of the indication, however, and think someone here might be able to provide some insight. The issue of the voltmeter indicating low (slightly above the 50% mark), charge light and parking brake indicator began a few weeks ago. They started flashing pretty sporadically, almost like a bad connection somewhere. I did a cursory under-hood peek and didn't notice anything. A week went by with no indicators at all. Then last week, the indicators came on sporadically and then solidly for a couple of days. Last night I make a quick hop to the store, started with the indicators lit up, drove a few miles, parked, did my business, came out and everything is wonderful...no indicators, full voltmeter reading. This morning I have no indicators and a good voltmeter reading. I'm guessing I ought to just pull the alternator out and run it over and get it checked out just to be proactive, but any other ideas? I've heard the most common issue with these alternators is the wearing of the carbon brushes...should I yank it and see how they are wearing?

amgraham

Go by Advance or some place that can check your charging system, preferably while it is acting up. Or, get yourself a cheap voltmeter so you can check it yourself whenever it does it. All you do is put the leads on the battery terminals and check the voltage (if charging properly it should be somewhere between 14 and 14.5 volts, if not then it'll be closer to 12). If it is charging there you probably have a bad ground somewhere. It sounds like a ground problem to me since you didn't mention anything about it not running well or stalling or anything like that when it's acting up.

Hopefully that helps you. Let us know what you find out. You can get a voltmeter at walmart or radioshack or something, should be less than $10.

amgraham

Oh, and another reason it seems to me to be a ground or connection is generally if an alternator has a problem it just quits working all together. It doesn't normally go in and out.

bob200587

I was told that when those two came on at the same time it indicated the alternator was going out. And at least 3 times on my own truck I've found this to be true.

MMA_Alex

i had them come on and off on a 6 hour drive once. they were on and off gradually more on than off, and the last hour or so they were on the whole way. Long story short my alt died, but did it gradually. Also earlier in the drive when i started it I heard a slight pulley noise after stopping from lunch. Anyway if it keeps coming on and off its probably a bad ground, but my point was that it could be the alt on its way out.

Some auto parts stores will check your alt for free, so thats probably worth doing

sleestak240

Yeah, I ran checks on the fusible link, engine fuse, and charge fuse and they all check out per the FSM. Leads between battery terminals shows around 12-13, definitely not over 14. Started the truck up and not a single complaint from the voltmeter...

Now that you mention it MMA...I heard a quick sound from one of the pulleys while starting a few days ago, definitely something I hadn't heard in the past. I did take a look at my belts and everything seems fine...good wear and tension but it did bother me a little hearing it.

I'll run it over to one of the local parts stores and let them hook an alternator tester up to it and see what the result is.

MMA_Alex

I didn't think much of it either as it was pretty soft, and I could only hear it slightly for a couple seconds at a time at idle. Funny thing is that where the charge light finally ended up coming on is within a mile of the place on the same highway where my dad crashed his car a couple years back.

Not sure exactly what ended up dieing on mine, and I didnt have the time to do the work myself as I was busy packing for college, and had to drive the truck about 600 miles 5 days after it finally died. The OEM alt was pretty expensive though which sucked

mtnfreak

Sounds like your alt. brushes are worn out. At a certain point they'll be kinda loose in the bracket and can move around enough to affect charging. Pretty simple DIY fix with some help from the search function above. If you have a shop or store that will run a diagnostic for free, then take advantage of it.

sleestak240

Yeah, I was planning on taking it in and just swapping out some brushes on my own after I take a look at them and get the alternator tested. Just for the record, I did my homework and used the search function...I just wanted to get some feedback from people who have seen the intermittent light combo like I had been receiving.

MMA_Alex

i definately recomend replacing the brushes yourself if you have the time to mess around with it. I wish I had the time cause the alt was like $250 + install for the new one if i remember right.