1971 #544 Alternator overcharging issue

[Dave S.]

I have a 1971 car with the original 544 alternator. I understand there is an internal regulator in these units. My car is significantly overcharging all the time. I have installed a new Group 24 battery and the condition remained the same. Is it likely a faulty internal regulator is causing this.? If so does someone have a Delco or other part number so I can purchase a replacement.?
Any guidance is appreciated.

[Edward J.]

Re: 1971 #544 Alternator overcharging issue

Dave if you have a volt meter just check what the voltage output is at idle and at 2000 rpm. let me know. should be about 13.8to 14.2

[Patrick H.]

Re: 1971 #544 Alternator overcharging issue

http://ecatalog.smpcorp.com/STD/#/vehicles

I found that I could order these parts at the local auto parts store - and I don't mean AutoZone.

[Jim T.]

Re: 1971 #544 Alternator overcharging issue

You would have to find a auto parts store that sells AC Delco parts to get the AC Delco regulator. I use a local parts store that sells AC Delco parts.

[Mark E.]

Re: 1971 #544 Alternator overcharging issue

Rockauto.com is a source for many Delco parts too.

[Patrick H.]

Re: 1971 #544 Alternator overcharging issue

You would have to find a auto parts store that sells AC Delco parts to get the AC Delco regulator. I use a local parts store that sells AC Delco parts.

98% chance that whatever you buy today in an ACDelco box is made by Standard. That's why I gave the link.
I think that the quality of a Standard part is going to be at or better that of an ACDelco part in 2017 (2018) however, in case ACDelco decided to save $ and source elsewhere.

[Duke W.]

Re: 1971 #544 Alternator overcharging issue

What Patrick said. GM hasn't made ignition/charging system replacement parts for over two decades. Any name brand replacement is fine and most are made by Standard Motor Products... just a different "brand" and marketing channel. Buy on price and convenience.

Check the side connector to be sure the terminals fit snug on the regulator spades. If one is not making good contact you get an overcharge situation. If the other, it's no charge. Be careful because one of those wires is hot all the time.

It's easy to separate the alternator case halves and change the regulator, but you should go through all the checks in the COM, and as long as it's apart is might be a good idea to replace the brushes.

Duke

[Dave S.]

Re: 1971 #544 Alternator overcharging issue

Thanks guys for the guidance.
Ill check the voltage and repair accordingly.
HNY

[Dave S.]

Re: 1971 #544 Alternator overcharging issue

With the engine fast-idling, check the voltage between the output terminal and alternator case. And again between the red wire (sense) in the connector and the case.
If the output voltage is high, but the sense voltage is nominal, the regulator is performing correctly. (There is a wiring issue causing a voltage drop in the output circuit).
If the sense voltage is the same too-high voltage as the output voltage, the regulator is faulty.

Wanted to report back. Problem was the Internal Regulator. Found an NOS D668 - #1116387 in a string box for $6. Easy replacement and all is working as it should. Many thanks to all.