83 Delta 88 Alternator Wont Charge

[Chris Tomas]

Your battery sounds like it's shot, too. The larger gauge charge line from alternator to battery will help with current draw (big amps, electric fans, high wattage lights, etc.), but won't (shouldn't) have any effect on voltage. A properly charging alternator will put out a minimum of 14 volts- any less, and something is wrong.

It's possible its shot, but i've always used a trickle charger on it when its not be used by the vehicle, and that charges it ok.

I can call AMA (think its called AAA out in the US) and have them test the battery im sure.

 

[Longroof79]

Chris,
are you getting 14 volts from the alternator itself?
It's possible that you could have a bad cell in the battery...even though it's new. It's usually unlikely, but weirder things do happen.

 

[Chris Tomas]

Chris,
are you getting 14 volts from the alternator itself?
It's possible that you could have a bad cell in the battery...even though it's new. It's usually unlikely, but weirder things do happen.

Sadly its not. The original alternator and 1st one i swapped in, so far have not outputted more than 12.8 volts max. The 2nd one i installed over the weekend only outputs 11.90v, and oddly keeps the charge light on with the motor running, while the other two did not.

A bad battery is possible, i wont deny it, but I'm gonna have the alt tested. Perhaps if the battery was shot, would it kill every alternator i install in it?

 

[Wageslave]

You being an electronic guy, I assume your voltage meter is working properly. I threw out one, it read about 2 volts low. The current Sunpro volt meter in my 88 Cutlass also reads 1V low.

Some of those voltmeters have a potentiometer that can be adjusted to make the gauge accurate. Check where the backlight light bulb goes into the back of the gauge. I have had to correct a couple of mine in the past.

 

[fleming442]

A bad battery will crush the rectifier bridge in an alternator in a heartbeat.

 

[Chris Tomas]

A bad battery will crush the rectifier bridge in an alternator in a heartbeat.

🙁 Shitty. Glad to know though! Will be getting my battery tested this week too.

Also, the alt tested bad at partsource today! I had a feeling it was a POS.

Got another alt under warranty from the junkyard, the guy who there said if this 3rd one dont work he'll just refund me, would have gotten that tested too at partsource but the guy who works the machine had left home.

Probably whats gonna fix this vehicle is a new battery and alt.

 

[Chris Tomas]

Thanks everyone for your contributions so far, the alternator was indeed bad according to partsource!

I'll most likely be getting a remanned alt from partsource (friday is payday 😀), and i will have that tested before bringing it home. Junkyard is refunding me too.

Also will be bringing the battery for testing, as if it is bad according to fleming442, then this charging problem could be a combination of things.

 

[airboatgreg]

What people do not realize is that an alternator is designed to keep a battery charged. They are not designed to charge a dead battery. I have not read the whole post but get a voltmeter and put one lead on the alternator output. Big wire on back. The other lead on the positive battery post. Should not be more than about a .2 volt difference. Then put one lead on alternator case and other on negative battery post. Should have same result.

 

[Chris Tomas]

What people do not realize is that an alternator is designed to keep a battery charged. They are not designed to charge a dead battery. I have not read the whole post but get a voltmeter and put one lead on the alternator output. Big wire on back. The other lead on the positive battery post. Should not be more than about a .2 volt difference. Then put one lead on alternator case and other on negative battery post. Should have same result.

This is true, but if this battery is bad, its definitely in the beginning stages, because it charges fine on a trickle charger.

But ill double check the readings again, i dont have a difference now with the positive battery cable bypass, but with the wiring harness there was a .2 difference for sure.

 

[Chris Tomas]

So an update here on the issue. My battery and alternator both tested bad, so i got kal tire to swap my battery under warranty, and partsource to replace the alternator...

Well, i installed everything and things didnt work as expected :/

In fact, i think i FINALLY figured out why the previous alternator went....

Because after installing the new parts, the alternator wasnt spinning, the fan was BARELY turning. So theres some real friction preventing the pulleys from spinning freely. The alt belt feels tight, but the belt behind it isnt. Revving the engine did nothing. Charge light still remains on with the motor running 🙁

The issue is i don't think i have the tools to remove the clutch fan to get to the belt 🙁

When the car had its water pump replaced and the alternator belt back in Jan 2017, an old coworker helped do the work due to my health conditions, and he said iirc the power steering belt should be replaced eventually.

Was too lazy to take a photo of my engine bay right now but heres a photo i edited to illustrate my point. The belt pointed in red arrows seems very loose as i said,doesn't even seem to have teeth to grip the pulley anymore..... Feels very flat rather.

I'm more familiar with the electrical side, so pardon my stupid question, but could the bad belt behind the alt belt (which i think is the power steering belt as previously stated) prevent the alternator and clutch fan from properly spinning? How do i tell if its the pulley or belt?

Is it possible to snip off the worn down belt to potentially reduce the friction, since the car wont drive anywhere?

I just want to see if i can get this alternator to charge my battery,so if it is the power steering belt causing friction, by the time I get that repaired at least ill have the charging issue out the way.


I'll post a youtube video later if that helps. Thanks for the patience guys!