Bad battery or alternator?

It's not your alt that killed your battery. It's your battery that killed the alt. If the battery had a bad cell for a while then the alt works it's ass off to try to bring it back to 12.7V or so. It can't cause the cell is dead.

As far as getting the alt back on I've had to take a grinder to shitty auto parts alts in the past to get them to fit over the bushing.
 
It should move. That is just a copper bushing to hold the alternator tight. Try a larger box socket on one side and a smaller socket on the other side and press the sockets together as you would do with U-joint removal. Don't hammer as it will break the bracket.

I don't adjust that.

That's good to know for future reference!


As far as I know, no.

Measure the alt width, then the opening. If it won't fit, bring it back to AZ, compare the two and try again.

I guess you didn't buy that Dremel did you?

No Dremel for me. Been making due with a cheap HF version for a while. Need to get a real one though! As for measuring — that's pretty much what I did. :cool:

It's not your alt that killed your battery. It's your battery that killed the alt. If the battery had a bad cell for a while then the alt works it's ass off to try to bring it back to 12.7V or so. It can't cause the cell is dead.

As far as getting the alt back on I've had to take a grinder to shitty auto parts alts in the past to get them to fit over the bushing.

Interesting. I'll have to think on that some but it certainly sounds plausible.

I seriously considered grinding it down, and I would have if I couldn't adjust that sleeve. But I decided to exchange it again first and try to get a better fitting one.

So off to the parts store I went because I decided that I wasn't going to screw with it all day. But first I grabbed my digital calipers and measured the new alt. It measured in at 58.23mm.


After discussing it with the parts store guy, I asked to see my old alternator. I measured it at 58.03mm.

I then requested a new alternator but of course they were out. I advised them that all 3.4L 3rd gens had the same size alternator but that 1999-02 came with a slightly beefier 80amp alternator. Luckily, they had one in stock and I measured it too. It measured 57.90mm


May not seem like much, but it was more than enough to prevent the first alternator from going back in.

So while a pain in the ass, I did get a slightly beefier 80amp piece of shit alternator — all under warranty.

It really goes to show you how crappy the parts store brands are in comparison to OEM stuff. I plan to keep an eye out for a used OEM alternator and rebuild it as much as I can. Or just buy a new Toyota reman one.

My truck is now on its 4th alternator first was OEM, then AZ one and then another AZ one, and finally today's alt from AZ. So while they are free under warranty, I don't like being stranded and I don't like swapping junk alternators all the time either. So no more. These things are junk! Even my new one seems to be all over the place voltage-wise — though nothing alarming.

It started off at 14.1 volts but has bounced around between 13.4v — 14.1v even though conditions hadn't really changed. So I don't expect this one to last more than a year. Hopefully I'll have swapped it out before then.

I did test the "new" 1999 alternator once I installed it though and it was putting out 13.9v which is kinda strange because the ScanGauge was reading 14.1v. Meh...whatever I guess.


 
As the old saying goes, size matters. And here, most definitely.

Being made in Mexico at least is a plus. Usually parts I have found being made there are more reliable than from the PRC. I have had some alts, starters, and other pumps last for years with no problems from the big box stores. Others die in days, weeks, or months.

Good to hear you are back on the road Creeping along.....
 
Glad you got it figured out. If you want to read my experience with some battery and alt issues read this thread from post 20 on. It's a good read. I'm thetoaster on that site:

Van down, electrical

Good read indeed! Now I want to look into those vans! Do you still have the van? Gone through anymore alternators after you fixed the wire?

As the old saying goes, size matters. And here, most definitely.

Being made in Mexico at least is a plus. Usually parts I have found being made there are more reliable than from the PRC. I have had some alts, starters, and other pumps last for years with no problems from the big box stores. Others die in days, weeks, or months.

Good to hear you are back on the road Creeping along.....

Yeah I had it in my head that it was some Chinese junk. Was surprised when I saw it was made in Mexico.

Definitely back on the road creepin. The Creeper lurks again....

 
It really goes to show you how crappy the parts store brands are in comparison to OEM stuff. I plan to keep an eye out for a used OEM alternator and rebuild it as much as I can. Or just buy a new Toyota reman one.

My truck is now on its 4th alternator first was OEM, then AZ one and then another AZ one, and finally today's alt from AZ. So while they are free under warranty, I don't like being stranded and I don't like swapping junk alternators all the time either. So no more. These things are junk! Even my new one seems to be all over the place voltage-wise — though nothing alarming.

I had similar experience before I really knew about car parts. I kept a spare AZ alternator in the GM truck I had (I was young and stupid and owned a GM) because it would either seize up and snap a belt or stop working within 12 months. For Toyota, if you want it to work well, OE parts for starter and alternator (and many other parts) seem to work best.

Thanks for sharing this, hopefully someone else won't go down that road.
 
I had similar experience before I really knew about car parts. I kept a spare AZ alternator in the GM truck I had (I was young and stupid and owned a GM) because it would either seize up and snap a belt or stop working within 12 months. For Toyota, if you want it to work well, OE parts for starter and alternator (and many other parts) seem to work best.

Thanks for sharing this, hopefully someone else won't go down that road.

Everyone goes down this road even after reading stuff like this. I just installed crap alt in friends car and told him I would only warranty the work if he went OEM. He agreed and when I get there he said it's okay he got a cheap one with lifetime warranty. I was pretty upset and told him I won't warranty my work or replace it again when it fails. I showed him forums online of how crappy they are and he didn't care. Warranty makes people feel good but don't mean it's quality.
 
Check Alt Brushes First

Sorry I didn't had enough time to go through how far your reached ending with replacing your alternator and battery.

My advice as follows:
I think you alternator brushes went bad.

Alternators dosen't go out just like that,, i had an alternator with two working diodes out of three and still working fine, yes overloaded but working fine.

Even though you are thinking that your alternator died im 95% sure that the brushes went out, its easy to replace and costs nothing. I got OEM for $10 last week.

If you still have the old alternator it may be worth to replace brushes and keep it as spare or resell it.

In your case Alternator went our resulting in battery going low,, even when putting new battery you kept consuming without recharging.

As batteries dosen;t go out in one overnight, i suspect that your battery yes is old but may still have some life in it.

Next time, probably after many years, if faced similar situation please take a long steel thing and hit the alternator while engine is running, let a buddy watch battery light if it will go OFF when hitting the alternator. If so happened so then bad brushes.

The voltage test when engine is running while all lights and stuff are ON is for diode test. If 14.4 then all fine, if dropped between 13.8-14.2 still fine with idle but not fine when RPM is above 1500. If dropped below 13.8 you are having bad diodes.

Hope this helps,
At your disposal...
 

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Everyone goes down this road even after reading stuff like this. I just installed crap alt in friends car and told him I would only warranty the work if he went OEM. He agreed and when I get there he said it's okay he got a cheap one with lifetime warranty. I was pretty upset and told him I won't warranty my work or replace it again when it fails. I showed him forums online of how crappy they are and he didn't care. Warranty makes people feel good but don't mean it's quality.

To each his own! Working at a dealer in the service department opened my eyes to a lot of stuff out there, and we saw some of the most well maintained cars on the road (Lexus). You truly get what you pay for when it comes to cars.
 
Watch Out..!!

That's good to know for future reference!




No Dremel for me. Been making due with a cheap HF version for a while. Need to get a real one though! As for measuring — that's pretty much what I did. :cool:



Interesting. I'll have to think on that some but it certainly sounds plausible.

I seriously considered grinding it down, and I would have if I couldn't adjust that sleeve. But I decided to exchange it again first and try to get a better fitting one.

So off to the parts store I went because I decided that I wasn't going to screw with it all day. But first I grabbed my digital calipers and measured the new alt. It measured in at 58.23mm.


After discussing it with the parts store guy, I asked to see my old alternator. I measured it at 58.03mm.

I then requested a new alternator but of course they were out. I advised them that all 3.4L 3rd gens had the same size alternator but that 1999-02 came with a slightly beefier 80amp alternator. Luckily, they had one in stock and I measured it too. It measured 57.90mm


May not seem like much, but it was more than enough to prevent the first alternator from going back in.

So while a pain in the ass, I did get a slightly beefier 80amp piece of shit alternator — all under warranty.

It really goes to show you how crappy the parts store brands are in comparison to OEM stuff. I plan to keep an eye out for a used OEM alternator and rebuild it as much as I can. Or just buy a new Toyota reman one.

My truck is now on its 4th alternator first was OEM, then AZ one and then another AZ one, and finally today's alt from AZ. So while they are free under warranty, I don't like being stranded and I don't like swapping junk alternators all the time either. So no more. These things are junk! Even my new one seems to be all over the place voltage-wise — though nothing alarming.

It started off at 14.1 volts but has bounced around between 13.4v — 14.1v even though conditions hadn't really changed. So I don't expect this one to last more than a year. Hopefully I'll have swapped it out before then.

I did test the "new" 1999 alternator once I installed it though and it was putting out 13.9v which is kinda strange because the ScanGauge was reading 14.1v. Meh...whatever I guess.




Brother 13.9-14.1 is no good. Unless its just after start and battery is thirsty.
Take the ride for a reasonable spinn,, you probably did by now.
Voltage must be in your condition (new BAT + New ALT) is 14.3 with idle and high beam on with some other stuff.
should be 14.4 with 2000RPM with everything in ON.
if voltage keep 13.9 that means alternator is not good. (sorry)
check grounding wire from engine bay to Negaitve battery terminal.

Bad alternator will result in short battery life = buying new battery wasting money and when you fed up with that then you will obliged to get OEM ALT.

Im having 2.7 with its OEM 18years ALT just replaced brushes and voltage is 14.3 during idling when everything is ON including blower fan. (not showing OFF but to let you have a idea.)

Hopefully all of the above is not the case but the battery was thirsty sucking all the current from ALT.
 
Brother 13.9-14.1 is no good. Unless its just after start and battery is thirsty.
Take the ride for a reasonable spinn,, you probably did by now.
Voltage must be in your condition (new BAT + New ALT) is 14.3 with idle and high beam on with some other stuff.
should be 14.4 with 2000RPM with everything in ON.
if voltage keep 13.9 that means alternator is not good. (sorry)
check grounding wire from engine bay to Negaitve battery terminal.

Bad alternator will result in short battery life = buying new battery wasting money and when you fed up with that then you will obliged to get OEM ALT.

Im having 2.7 with its OEM 18years ALT just replaced brushes and voltage is 14.3 during idling when everything is ON including blower fan. (not showing OFF but to let you have a idea.)

Hopefully all of the above is not the case but the battery was thirsty sucking all the current from ALT.

I agree. All these others saying 13.8 is okay but imo it's not. 14.3v is what my 20 year old alt holds.
 
You will also need to get a proper positive battery terminal. Get the OEM battery terminal. It is well built and not too expensive.
 
just for future reference.
that little bushing in the mount is meant to adjust and be slid back. they are on MANY different rigs. its not really a sign of quality, or lack of, if a particular alt doesn't fit in that space. that's WHY that bushing exists...


also, 13.8-14.2 is pretty much a standard for good alternator output.
 
With no load the battery should be 12.7 volts.
I would check it with one of the cables disconnected for a bit.

That also gives you a reference point for your multi meter.

The FSM shows the charging voltage with no load at 2000 rpm's as
14-15 volts @ 77 degrees F
13.5-14.3 volts @ 239 degrees F.

I can only assume that's the temp of the alternator.
 
Good read indeed! Now I want to look into those vans! Do you still have the van? Gone through anymore alternators after you fixed the wire?

I still have the van. It's been sitting since I purchased the 4Runner. A few days ago I realized I hadn't even started it in three months. So I grabbed my keys and she fired right over. A short drive and it's back in the driveway. lol I'm planning on selling it at some point to help offsett the ridiculous amount of money I'll end up putting into my 4Runner.

Since I fixed that wire behind the fuse box the van has been running perfectly. I also put in a Denso alt at the same time so I expect it to be fine. There great vehicles if you do your own wrenching. They make some of the hard to get at stuff on the 4runner look easy. lol
 
A alternator will not charge your battery back up to 12 volts, if the battery is at 10 volts that is all the alternator will put out. A generator putts out 12 volts no matter what, In the good old days, as long as you didn't turn the car off you were go to go.
 
I would say bad battery. Exact same thing happened to my 3rd gen a few months back. Replaced the battery and haven't had any problems since.
 
Battery light on and RPM reads at 0 even though engine runs normal?

My 3rd gen 4runner is doing the same thing [MENTION=115590]StreetCreeper[/MENTION] mentioned.

It started kinda sluggishly, and after driving a few blocks my battery and ABS lights popped on. then my RPM gauge started moving all wonky and finally rested at 0, with no noticable changes to the engine running at all. I stopped to double check connections, fluids, etc. It was off for about 5 mins and upon restart, she barely started [due to low power] headlights and dash lights were very dark and clearly not getting power but engine seemed fine and got me home luckily.

I'm gonna get my battery and alternator tested obviously, but the RPM gauge has me freaked. Could this be an electrical problem as well?

Help! I'm worried!
 
I didn't read all the post because most of the time people are always giving bad advice. So my version of the bad advice is to crank said vehicle and unplug the battery. If the volt meter is still reading anything below 13 volts its a bad alternator. If the car dies when you unplug the battery its a bad alternator. If neither of these happen then its a bad battery.
 

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