Alternator Going?

00GTP4ME · #1 12-21-2010, 11:38 AM

I bought a 110 amp alternator from AutoZone last year to replace the factory alternator that went out and haven't had any issues until this winter. Sometimes (usually in the morning when it's really cold) the voltmeter will only show that I'm at 12V (sometimes less) when I'm idling (after the engine is warm). Then when I start driving the volts go up as the RPM's go up. Other mornings, the volt gauge says 14V+ and the alt seems to be putting out a ton.

I do have a stereo system with subs, 1.6 farad capacitor, etc, and sometimes the volts output seems affected by having the stereo on and sometimes it seems completely unaffected.

This issue has caused me to have to jump the car sometimes (the battery acts as if it's dead), but what's strange is that sometimes it starts right up without hesitating.

It seems like the alternator is on it's way out, but could anything else be causing this? The last time I had to replace the alternator, it would just never go above 12V as if I didn't even have an alternator. This is a little weirder. Could I have a weak alternator bearing or something?
I still have the same duralast gold battery that was in the car when I purchased it so at minimum the battery is 5 years old. Could a floating short in the battery be causing this?

Thanks for any help....

BNaylor · #2 12-21-2010, 11:58 AM

I've had good luck with AZ Duralast batteries but best to take it to the Zone and get it tested. However, bad luck with AZ rebuilt/reman parts. The voltage fluctuation and change due to load is normally a flaky voltage regulator in the alternator.

You sure a 110 amp alternator is good enough considering your sound system?

00GTP4ME · #3 12-21-2010, 12:03 PM

Quote:

Originally Posted by BNaylor

I've had good luck with AZ Duralast batteries but best to take it to the Zone and get it tested. However, bad luck with AZ rebuilt/reman parts. The voltage fluctuation and change due to load is normally a flaky voltage regulator in the alternator.

You sure a 110 amp alternator is good enough considering your sound system?

Hey Bob. Yeah, you're probably right. The problem is that I need to take the car to AZ and have them test the alternator when it's acting up otherwise I don't think they'll warranty it if it tests out during one of it's behaving times (at least if they're anything like Checker was when I worked there).

No, I would much rather have a higher output alt, but I have no clue where to find them! O'reilley's seem to top out at 110 amps too!

I haven't had great luck with Napa parts so usually avoid them. What do you recommend?

Scrapper · #4 12-21-2010, 12:07 PM

Quote:

Originally Posted by 00GTP4ME

I bought a 110 amp alternator from AutoZone last year to replace the factory alternator that went out and haven't had any issues until this winter. Sometimes (usually in the morning when it's really cold) the voltmeter will only show that I'm at 12V (sometimes less) when I'm idling (after the engine is warm). Then when I start driving the volts go up as the RPM's go up. Other mornings, the volt gauge says 14V+ and the alt seems to be putting out a ton.

I do have a stereo system with subs, 1.6 farad capacitor, etc, and sometimes the volts output seems affected by having the stereo on and sometimes it seems completely unaffected.

This issue has caused me to have to jump the car sometimes (the battery acts as if it's dead), but what's strange is that sometimes it starts right up without hesitating.

It seems like the alternator is on it's way out, but could anything else be causing this? The last time I had to replace the alternator, it would just never go above 12V as if I didn't even have an alternator. This is a little weirder. Could I have a weak alternator bearing or something?
I still have the same duralast gold battery that was in the car when I purchased it so at minimum the battery is 5 years old. Could a floating short in the battery be causing this?

Thanks for any help....

i got a 83 buick that's over chargeing and it's the battery that's bad not good on the alt. and like he sais duralast is best battery i've bought and still will buy duralast if battery go's bad.

BNaylor · #5 12-21-2010, 12:09 PM

Quote:

Originally Posted by 00GTP4ME

No, I would much rather have a higher output alt, but I have no clue where to find them! What do you recommend?

The HO alternator. We have some old discussions and sources, mostly on-line. I'll see if I can find some.

00GTP4ME · #6 12-21-2010, 12:16 PM

Yeah, I just checked Napa just for kicks and they didn't have anything higher than 110 amps either.

So do you think I should just eat the warranty on the AZ alternator and start fresh with an HO one?

tblake · #7 12-21-2010, 02:16 PM

Hey Matt,

Bring it to AZ for testing, if its bad get a replacement under warrenty for the time being. Then look for higher output ones. Are you sure your system is turning off properly when you shut the car off?

Otherwise, I know the PCM wont command the alternator the charge until a few seconds after the car has started. Sort of a failsafe to keep the alternator from going full field right away and burning up the regulator.

I'd take the batt and alternator in for testing.

00GTP4ME · #8 12-21-2010, 02:36 PM

By system, do you mean stereo system? If so, then yes, I know everything shuts off when the car does.

If not, then I'm not sure. Everything looks shut off when I leave the car....

00GTP4ME · #9 12-21-2010, 03:51 PM

Would an alternator from a '98 Bonnie SSEI be a direct swap?

tblake · #10 12-21-2010, 07:05 PM

Yes, system I meant sterio system

And no, 98 and previous years are different. Brackets bold up different. It will not work.

You need 99+

00GTP4ME · #11 12-21-2010, 11:18 PM

K, so a 99+ and I'm good....

I didn't get to an AZ today, but I'll try very soon.

00GTP4ME · #12 12-25-2010, 10:22 AM

Well, I tore out the alternator and took it to AZ to have it tested and everything tested out well. I was afraid that would happen, because the alt does behave half the time. I also checked out the Bonnie alt's and they seem to be completely different in terms of mounting design, so that was out (the alt for the '98 was the same for the '99). So as a hail mary I put in a new battery and new battery cable bolts and that didn't change anything.

So. Anyone have any ideas? Any idea as to where to get an HO alternator for these cars?

EDIT:

For my info, here is one JC Whitney has for pretty cheap. 200 amps.

http://www.jcwhitney.com/bosch-alter...d1833y2000f6j1

BNaylor · #13 12-26-2010, 09:09 AM

Quote:

Originally Posted by 00GTP4ME

Any idea as to where to get an HO alternator for these cars?

Suppliers on EBay or Amazon.com have them. 220 amp. See link below for an example.

Click here

richtazz · #14 12-27-2010, 09:58 AM

Since the battery is 5 years old, and it seems to act up only when it's extremely cold out, I would suspect the battery is on it's last legs. It's 5 years old, and you have a bunch of add-on stereo equipment that adds additional strain on the electrical system. Since the volt guage in the car reads system voltage, when the battery is extremely cold, the dash guage will read lower until the battery is warmed up a bit and will accept a charge. I would double check alternator output with a volt meter rather than trusting the in-dash guage.

00GTP4ME · #15 12-29-2010, 10:44 AM

Hey Rich. Yeah, I got a new battery and that didn't change anything. It's weird - it's like I only have the low voltage reading when I'm idling. Once the car starts going, then the volts go up with the RPM's. My first notion is to now just get an HO alternator, but I'm not sure if that will fix it. It seems like the current alternator just isn't spinning fast enough when idling. Wouldn't an HO alternator potentially have the same problem? Or does an HO alternator put out more electricty per pulley revolution?

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