Trying to get my 70 going. The alternator went bad, and I abandoned the project, rolled the car in the corner of the shop. Well, a year later, I want to finish the saga of the bad alternators. It is a 225 car, now sporting a 360. I've had it working in the past... but now I can't get it to charge. I bought a Napa alternator, that one night on the way home, started over charging. I shut down all electrical, as the headlights looked like xenon! I just took the belt off, and drove it literally 1/4 mile back to the house.No wires appeared melted or fuses popped. They confirmed the alternator was not operative. Anyway, freaggin 4 auto parts store alternators later... here I am resuming the project. Am I missing something? I put the battery lead on with a nice clean nut on the clean alternator stud. Then, I put the green wire with the female connector on it it on the only field terminal there is. Am I missing something else??? Thanks guys.

this might help...i believe starting in 1970, the alternators used a dual field along with an electronic voltage regulator..


there is a pdf file attached.

so questions come to mind.
first, how many wires do you have?
are you expecting 2 fields?

if not, have you checked the voltage reg?
are you getting power going in? power going out?

what voltage reg is it?

If all that checks out and you still aren't charging, have you checked the amp meter? see if power is coming out of it?
bypass it? put both wires on one stud on the back of the amp meter see if you charge then?

or bypass the bulkhead entirly and put a wire from the back of the alternator big bolt/charging directly to the postive of the battery.
10 to 12 gauge.

OK... this is where electrical idiots like me need to stop doing the " touch the wire quick test"!!! I have one wire that looks like a sending unit wire ( mini spark plug boot) unused, a dark green wire with a factory female, a dark blue wire factory female, and the 12V source wire of course. My alternator has 1 field spade.... which I am guessing I have wasted yet another damn $60. I should have asked first before listening to the local " I have been around Mopars all my life" counter [Edited by Moparts - Family Friendly Site - Keep it clean]. Anyway, I have 1 field spade. I switched the dark green one on there, to the dark blue. It is making 13.30 at the battery at idle. I blipped the throttle once, it went to 15V, I immediately shut it down once I saw above 13.8-14.2. The charging needle isnt pegged, but it is WAyyyy to the right and bouncing at idle. I'm guessing I have yet again, the 6th wrong damn alternator. I should have GM 1 wired it and been done with it I suppose.

If it has a "box" reg with the 2 terminals on either side see if you have fire at the blue "ign" terminal on one side when you turn the key on & from the "fld" terminal on the other side with the green wire that goes to the alt field see if you have fire at the alt field with the key on. If good there & the alt is good then either the reg is bad or it ain't grounded. If you have a flat reg with the triangle connector which has 2 terminals you need an alt with 2 field terminals & the two (alt/reg) are connected with a blue and a green wire. The blue & green wires can go on either alt field terminal but the blue wire must go on the top terminal on the triangle & the green wire goes on the triangle side terminal. Switched 12V from the ign sw out thru the bulkhead (the blue ign1 circuit) which goes to one side of the "box" reg but on the later reg it T's into the blue wire that goes from the reg to one of the alt fields. If it ever full fields again IMMEDIATELY pull the connector off of the reg rather than the fan belt till you get it figured out.

The alternator on the left is what I returned as "not the right one" I am thinking now, that I might not have put both field wires on... dohh.. That is my fault if so. The local know it all Mopar guy at Napa said " these square back alternators have the built in regulator, your 70 did not come with that."


I have the flatter style ( newer) regulator with the triangular plug. I only have 1 field spade. I see where there is a cast "field" with a screw hole on there... so at one point, this remanned alternator was a 2 field alternator but is not set up like that now. It sounds like I have bought yet again the wrong one. You can't return electrical, but I have spent $567,203 on alternators, so whats another $70. Heck, I might buy one for a 1986 Rolls Royce, see if that works!!! Thanks for your help... man oh man. Too many options... alternator

Rapid thanks, I just edited my post as you replied... See my link above, that 2 wire ( square back) is what I could not get to charge... but dummy me had one of the field wires tucked under the heater hose. Again, that's my fault, and.... quitting the project for 1 year, simply did not catch it. So, if I am lucky, they will take this 1 field back, and give me the one they have with the " built in regulator rectangle back" to me...
The Gomer was adamant that the 2 field I had was a built in regulator, as it has the square back cut into it. That's what I did. I did not see my other field wire tucked under the heater hose during the removal/storage. I am a jerk, but you guys are straightening me out. The biggest question is this. Does it matter which field wire goes on which field terminal?

The biggest question is this. Does it matter which field wire goes on which field terminal?

Did you look at the pdf file I posted that is attached to the second post..????

UPDATE- Thanks to you guys, I put the other field wire on, and 13.58-13.70 at idle or 4,000 rpms or so. Thanks again. My lesson learned is if you put a project away, label stuff! Ha