Alternator wiring

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dartsixty7

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I know this subject has been brought up before several times. I've used the search feature and found all the different wiring diagrams to wire up the square back alternator for the early type charging systems. My question is: I know I have to run a wire from the second field post on the alternator to the voltage regulator, do I really need to splice into the wiring on the voltage regulator or can I just use a splitter on it and attach it that way. The voltage regulator I am using looks like the original black box, except mine has the circuit board internals. Thanks in advance.

Dan in Silicon Valley
 
OK, you are using a 70/ later "isolated field" alternator with two field connections

WHAT are you using for a regulator?

If you are still going to use your original 69/ earlier regulator all you need to do is:

Connect the battery output post just like the old alternator

Connect your regulator (green) wire to one of the two field connectors.

Ground the second field connector

=====================================================

If you are going to change to the newer 70/ later regulator, connect the green field connection on the regulator to one of the two field connections on the regulator

Connect the OTHER field connector at the alternator to "ignition run."

This may be where the splicing your are referring to. You want to hook this second field connection to the blue "ignition run." factory wireing. This used to go two places. One is the coil resistor, the other is the ign terminal of your old regulator.

So now it must go to a third point, the new second field connection.
 
I've upgraded to the electronic distributor, so I'm running an electronic voltage regulator. I'm using one that looks like the original black box, all I want to know is instead of splicing into the existing wire, could I run a wire all the way up to the voltage regulator and attach the wire to the ignition post with a "Y" or "T" connector.

Thanks,

Dan in Silicon Valley
 
I'm pretty darn certain the answer is yes, that wire you want to splice into is just a connection to the field post of the voltage regulator. Now I'm going off of points based knowledge so wait for a second affirmation.

you can just run that wire...
 
I finally had some free time to change out the alternator today. I ran a second wire to the ignition side of the voltage regulator. Instead of splicing into this wire I just used a connector the slide onto the post and has to 2 prongs that wires can plug into. After I adjusted the belt I started the car. Now the amp meter shows just a little towards the discharge side at idle and when I turn on the head lights or radio or both it now plunges into the discharge side. The engine idle speed doesn't change. Is this something I need to worry about or is the alternator not functioning, it's a used unit that a friend gave me, he bought it new and then decided to change over to the one wire GM style. I did check the wires and they are not getting hot, no smoke or smoldering wires.

Thanks in advance,

Dan in Silicon Valley
 
If you are using the "normal" vintage Mopar alternator, it is well documented that they don't charge much or at all at low RPM. If it works "as normal" off idle and cruising, the setup as you have it should be considered normal

You might read this post to see how the overall system voltage drop is doing

http://www.forabodiesonly.com/mopar/showthread.php?t=141911
 
The alternator is the square back style; 70 - up. I've upgraded to an electronic voltage regulator so just grounding the second field wire isn't going to work. I thought the 70-up alternators put out more than the older style alternators. The problem I had with my old alternator was that the alt gauge was always bouncing around the charge side, now at idle it's just south of the middle, when I turn the headlights on it goes to the middle of the discharge side, the radio doesn't effect it that much. Tomorrow I'll check to see if the voltage regulator is grounded sufficiently. I might also see about installing a higher amp alternator to see if that fixes things.

Thanks

Dan in Silicon Valley

PS 67DART273, your car is the same color as mine, dark copper, but mine has a white vinyl roof with white interior.
 
Actually, mine was originally dark green, I "think" and has been red at some time, is now black. "It's a driver."

Depending on where you got your squareback, if some $$$$#@#@# rebuilder has been into it, it's hard to say what stator/ rotor combo it's got, and what amperage it REALLY is supposed to be
 
You say you are using the regulator that "looks like the original black box". That's a little bit ambiguous; the original '60-'69 regulators were a black box with one "IGN" terminal on the right side and one "FLD" connection on the left side, and the original '70-up electronic regulators were a black box with white or yellow ink stamp ("Chrysler electronic voltage regulator 3438 150" etc) and a single triangular rubber-booted 2-wire connection on the front of the box. Nowtimes, there are several different electronic replacements for the '60-'69 style regulator that fit, hook up, and more-or-less look like the original '60-'69 units. Which exact type of regulator do you have? I am guessing that you mean you have an electronic version of the '60-'69 regulator. In that case, you ground one of the squareback alternator's two field terminals -- it does not matter which -- and connect the car's one and only field wire to the alternator's other, non-grounded field terminal.

Green1 is correct, you cannot just toss a big-amp alternator into an early car without risking extensive and expensive damage. See here and follow the links it contains.
 
Yes, the voltage regulator I have installed is an electronic voltage regulator that looks like the old style ones. I thought I had to run a wire from the second field post on the alternator to the ignition post on the voltage regulator? I thought you only grounded the second field post if you were keeping the old regulator and didn't have electronic ignition. Could my problem with the amp gauge be because I didn't splice into the wire but instead used a splitter to attach the 2 wires to the ignition side of the voltage regulator?

Thanks for the replies

Dan in Silicon Valley
 
Yes, the voltage regulator I have installed is an electronic voltage regulator that looks like the old style ones. I thought I had to run a wire from the second field post on the alternator to the ignition post on the voltage regulator? I thought you only grounded the second field post if you were keeping the old regulator and didn't have electronic ignition. Could my problem with the amp gauge be because I didn't splice into the wire but instead used a splitter to attach the 2 wires to the ignition side of the voltage regulator?

Thanks for the replies

Dan in Silicon Valley

Here's how I did this conversion on my '66 Valiant with electronic ignition:

Electronic regulator that looks and wires like the old mechanical one... Check!
Newer square back alternator with 2 field terminals...Check!
Wire from one field terminal to ground. (Turned out to be about an inch long. It only has to go to the alternator case)...Check!
Connect old alternator wiring to the appropriate terminals on back of alternator...Check!

Yes, it really is that simple and has worked fine for 3 years now. Replace the wire you added with a wire running from the field terminal to the alternator case and you are ready to go.
 
Thanks guys, I'll do that first thing tomorrow. I guess I didn't need to go out and buy wire and connectors.


Dan in Silicon Valley
 
Yes, the voltage regulator I have installed is an electronic voltage regulator that looks like the old style ones. I thought I had to run a wire from the second field post on the alternator to the ignition post on the voltage regulator?

No.

I thought you only grounded the second field post if you were keeping the old regulator

You are keeping the old (style) regulator, it's just yours is electronic and not electromechanical now. Hookup is identical to the original '60-'69 regulators.

Could my problem with the amp gauge be because I didn't splice into the wire but instead used a splitter to attach the 2 wires to the ignition side of the voltage regulator?

You have miswired your charging system because you have misunderstood the electronic regulator swap you did. Follow directions (in this thread) and get your car back on the road, or keep on asking the same question again and again and the car stays dead. Yer choice!

redbeard.gif
 
OK, I took the wire off the ignition side of the regulator and have now run a ground wire from the second terminal to the top bolt that holds the alternator to the engine block. Now when I start the car up the idle is just like it was before I changed alternators. Idle is choppy, amp gauge needle jumps back and forth between the charge side and the middle and headlights dim. Does it matter which terminal I use for the ground or do I need to change my ground?

Thanks,

Dan in Silicon Valley
 
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