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1984 D100 w 318 and 3 spd + OD manual gearbox

pulled the alternator off while doing the timing chain

normally very careful about marking and noting which wire goes where - except this time

one wire goes on a post terminal secured with a nut - that is clear

there are two other wires with spade terminals - one wire is red and the other looks white but according to the Haynes manual wiring diagram is light green I believe

There are two terminals on the alternaor - this is going to sound dumb but it is the only way I can explain it - one is closer to the post terminal and the other is further away

Which one doe the red wire go on

Once I know that, my little brain can figure out which terminal the white and/or light green goes on

thanks for your help in advance
 

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To identify the (+) field circuit and (-) field circuit terminals on the alternator, look at the back of the alternator and put the "BATT" terminal at the 12 o'clock position. The two "FLD" terminals would appear as though they were at approximately the 10 o'clock and 11 o'clock positions. The terminal at 10 o'clock would be the (-) field circuit and 11 o'clock would be the (+) field circuit.
 

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Interesting.


I just put them on - and it charges...wonder if it makes a difference on the fields.
 

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Interesting.


I just put them on - and it charges...wonder if it makes a difference on the fields.
I don't think it does, since the alternator creates AC voltage then sends it to the voltage regulator that changes it over to DC. I could be wrong on this one though, just my hypothesis!
 

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since the alternator creates AC voltage then sends it to the voltage regulator that changes it over to DC.
The diodes in the alternator turn AC current to DC. I think there is three or four inside. Basically nothing more than one way check valves. AC in one side of the diode and DC out the other.

The regulator regulates voltage to the battery. It turns the field current on and off. In this case it is interrupting the ground side of the regulator. I would definitely make sure the wires are hooked up correct.

When the ignition is turned on one side of the regulator is wired into the same hot wire on the field wire. The other wire on the regulator is ground and goes down to the negative side of the field. The regulator acts like a switch turning on and off the ground i.e. on and off the regulator.

I think the earlier system interrupted the hot side of the field.
 

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The 2 spade terminal wires are field wires. It makes no difference to which field terminal they are attached. The alt will still charge. There may be a theoretical difference ( 1 pos field, theother neg) but it makes no practical difference.
I been wrenchin on Mopars since the early 80's (professionally for 18 years), and I have never had any trouble just stickin them wires on there. I bet I put on thousands of tem dual-field alts.
 

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I guess it's dealers choice. I know how I plan on hooking mine up when the engine goes back in. I think the idea here is to match the POLARITY of the BATTERY, ALTERNATOR and REGULATOR. What can it hurt?
 

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440 and a 4 speed
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darn it....no I'm gonna have to take a peek under the hood this afternoon...


I had to run two new wires from my reg to the alt, and like many before I just put them on.


I know it'll charge either way, but I guess it wouldnt hurt to hook them the way you describe...it'll just take a few minutes with the volt meter to determine which wire is which - unless you can tell me terminal off the VR is the positive one.....then I might just trace it.
 

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unless you can tell me terminal off the VR is the positive one
As your are looking at the regulator bolted to the firewall the terminal at the top left is the hot one. The wire should be red.

That same wire really should go to the positive field terminal which is closest to the big battery wire on the alternator as explained earlier. Your polarity will now be correct.

This is how they came from the factory.
 

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Thank you...


guess my 50 / 50 luck was good, as it was put on that way already...
 
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