Alternator Refuses to Charge. Need Help

[SETXTurbo]

Hello everyone, I've had my 1987 Grand National for about 8 months now and recently my volts light came on in the dash.

I had the battery tested, it tested bad, bought a brand new battery, installed it, and same issue. Volts light still on.

I started doing some testing with the multimeter and I'm getting 11.6-11.8 volts at the battery and at alternator with engine on. I also tested the brown wire that connects to the alternator and it shows high 11 V (similar to battery voltage).

Had the alternator rebuilt, reinstalled and nothing has changed. Volts light still on, and still in the high 11s at the battery and alternator.

It seems the power is not able to leave the alternator and make its way to the battery.

So my volts light is working, brown wire has juice, and connection point at alternator is good, new battery, new alternator. But still not charging.

Does anyone have any idea as to what is happening here? I'm lost at this point. Any help is greatly appreciated, thank yall.

 

[BEATAV8]

I’ve seen some local guys struggle with this recently. If your alternator rebuilder used a Chinese regulator in the rebuild that may be your issue. Autozone (and similar) units also seem to have problems right off the shelf.

The Remy (new unit) from rock auto has been a good part, and it’s priced right.

 

[SETXTurbo]

I’ve seen some local guys struggle with this recently. If your alternator rebuilder used a Chinese regulator in the rebuild that may be your issue. Autozone (and similar) units also seem to have problems right off the shelf.

The Remy (new unit) from rock auto has been a good part, and it’s priced right.

I appreciate the feedback. I'm going to bring the alternator back to the rebuilder, who has an extremely solid reputation in our area, and have him test it and test the input port. Is the Chinese regulators not compatible with turbo buicks or do you believe the alt is simply still bad? Thanks again.

 

[BEATAV8]

I appreciate the feedback. I'm going to bring the alternator back to the rebuilder, who has an extremely solid reputation in our area, and have him test it and test the input port. Is the Chinese regulators not compatible with turbo buicks or do you believe the alt is simply still bad? Thanks again.

The replacement regulator was blamed on the units I know of.

 

[SETXTurbo]

The replacement regulator was blamed on the units I know of.

You were spot on. I tested all of my grounds and wiring, finally pulled the alt off and brought it back to the shop and had them make it self exciting and problem solved. It was the replacement regulator. And like you said, this issue is becoming more common. Really appreciate your help on this.

 

[Chuck Leeper]

Is the Chinese regulators not compatible with turbo buicks or do you believe the alt is simply still bad?

The rebuilders buy the parts by the barrel. They grab a part, slap it in, and you get potluck junk.

 

[Turbo6inKY]

The rebuilders buy the parts by the barrel. They grab a part, slap it in, and you get potluck junk.

This.

Our saving grace is it takes five minutes to pull the alternator. Buy the lifetime warranty one and keep taking it back until you get a working one. Make a copy of the receipt and put it in the glovebox for when it dies in five years.

 

[steve hughes]

Any time i buy a starter or alternator i have it tested before leaving the parts store. Saves alot of return trips.

 

[SETXTurbo]

Any time i buy a starter or alternator i have it tested before leaving the parts store. Saves alot of return trips.

Steve, I witnessed the bench test after having the alt rebuilt, and it was good to go. That's really what was throwing me off. Good battery, good alt, good wiring, good volts light. It wasn't until I questioned the internal regulator when I found the real issue. I think it would be wise for anyone having their alt rebuilt to go ahead and have it self exciting to eliminate any similar issues with these foreign regulators. I hope this saves someone some time and effort in the future.

 

[GNVenom]

The alternator uses only one wire to excite the field, through a dash lamp. The other input in the regulator uses direct 12 volts, which is how they bench-test it. They don't test it with the lamp input, which is why some of them don't work out of the box.

Use only Delco parts, you won't ever look back.

 

[Chuck Leeper]

John, you are up early!
Shoveling snow before breakfast?

 

[GNVenom]

Ha! No snow here, that's down south in the ski towns.

Up at 5am every day. Old habits hard to break......

 

[Turbo6inKY]

Any time i buy a starter or alternator i have it tested before leaving the parts store. Saves alot of return trips.

None of the parts stores in my area have the dongles for the tester for our alternators anymore. they can't test them.