Charging issues help please.

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Fisher

Old Guy with a Cool car.
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71 Duster 20,000 mile car, was 6 cyl now 383 with electronic ignition conversion . Chrome box from Mancini. Car starts and runs great. The Alternator came from Source 440 its one of there 50 amp deals, dual field wires etc. Ok so the old alt was a dual field wire alt as well with th batt term. This new alt also shoots sparks out from the mounting brackets when you rev the car up. LOL . The battery is sitting at 12.3 Volts and there is 30 volts to ground coming out of the alt. The odd thing here is with a volt meter, and only the neg wire hooked up to the battery, i can go from the pos terminal of the batterye to any where on the car and get 12.3 volts. except the alt case? Once i connect the po terminal of the battery i get a ground reference from the alt case to pos. That makes no sense at all to me and should not be doing that. I am taking the alt to a local battery starter shop Monday morning to get them to spin it on the machine see what they say. I can see that the 2 field wires go to the sake location on the alt via brushes, so i gather one is for start and the other for run? so it makes no difference where the blue or green wire go there.
 
wow something hooked up wrong or not grounded and as far as charging you smoked your regulaor now . put in a 50 or 80 we just call it a floater . But they cant take sparking or they will blow especially the stock 1ns . put a few grounds in . The old wires get cracked also and cant take a ton of voltage or you will burn it down , so check for cracks in the harness ,you may have a problem there some where and tighten your new alternator screws and bolts ,every 1 assumes they are tight from the store , just like starters you have to tighten all the bolts before you install them . good luck with it .
 
The Alternator came from Source 440 .

I'll tell you what makes no sense and that is your entire post. First can you provide a link or something that shows a photo of this alternator? Or post a photo?

. This new alt also shoots sparks out from the mounting brackets when you rev the car up. LOL . .

This makes almost no sense. Every factory type Mopar alternator except the huge gigantic frame 100+ amp units of the 80's are grounded by the mounting bracket

... there is 30 volts to ground coming out of the alt. .

WTF? How exactly are you measuring this voltage? EXACTLY

The odd thing here is with a volt meter, and only the neg wire hooked up to the battery, i can go from the pos terminal of the batterye to any where on the car and get 12.3 volts. except the alt case? Once i connect the po terminal of the battery i get a ground reference from the alt case to pos.

What do you mean a "ground reference?"

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A PHOTO or two of this installation would go a VERY long way as to helping us out to find your problem. As of now, I don't even have an idea as to "what" sort of alternator you have
 
Wow seriously? LOL ok never mind.


Yes, SERIOUSLY. You can't give us more information than this? OK I'll look at my crystal ball

"It's broke"

Do you know what I run for an alternator? Of course you don't. I'm here and you are there. Can you see it? Nope. Well, neither can I. K?
 
To answer your question on the 2 field wires, no, it is not for START and RUN. The blue wire is the 12v feed from the ignition in RUN, and the green is the return to the regulator. The regulator works in this setup by varying the amount of reisistance to ground from that green wire connection; that varies the current flow through the filed winding and regulates the voltage out of the alternator.

If the alterantor checks out at the shop, then try this:
- Clean the metal to metal surfaces and scrape to bear metal where the alternator contacts the brackets and the brackets contact the block
- Make sure you have a - lead of the battery connected to clean metal on the block, and the ground strap from the back of the passenger side head to the firewall. Scrape these clean to bare metal too. Sorry if it is nice paint, but these groudns simply HAVE to be good and solid.
- Make sure the regulator case is grounded to bare metal to the firewall.

Disconnect the green wire from one alternator field connection and turn the key to RUN. There should be 12v at the blue wire to the alternator. Then re-connect the green wire and start the car. Measure the following with the - lead of your meter at battery - :
- Battery + voltage
- Alternator case (shoudl be very near to 0 volts)
- Voltage at the green wire on the alternator; should be around 2-3 volts less than battery + voltage
 
First off i get frustrated fast. What i did today was take the alt to the local shop and had them spin it. It was fine. The parts store i like had a new regulator on the shelf i got it home and used a diode tester to check it out, mine was bad. Installed new one and yes made sure the new one had a proper ground. I also grounded the alternator on the tab provided. All the issues are gone, its charging fine. and no longer shooting sparks off the mounting bracket. Thank you for the reply NM9
 
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