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3G Alt instal in a '70... some wiring help anyone?

  • Thread starter Thread starter Swede958
  • Start date Start date Feb 13, 2004

Swede958

Founding Member
Dec 17, 2001
712
0
0
Austin, TX
Feb 13, 2004
#1
  • Feb 13, 2004
  • #1
Hey everyone, well, put my extra discount to work and bought a 3G alt this week, picked up a socket for it and I'm getting ready to instal it. I have the diagram from the Bronco site Bronco Link , I'm just not sure how to apply it to my mustang.
Out of the voltage regulator I have three terminals wired. F, S, and A
F- Orange
S- Light green/Red stripe
A- 2 yellow, one of which goes to a condensor sharing a mounting hole with the VR.

Can anyone tell me what wires go where? As far as I can tell from the Bronco diagram... The orange wire will be capped off, the green/red one will run to the I terminal on the new alt, the yellow will just run to the + side of the solonoid. Is this right? Or should the green/red be capped off and the orange wired in... it is a higher guage wire?

Also two more questions... 1. I have a pertronix unit on my distributer and I wanted to know i I still needed to use that condensor? and 2. For those of you who did it, how did you hook up the 175amp fuse? Did you just put one end of the fuse on the + terminal of the solonoid and a small nut and bolt on the other end to the wire? Or what? I was thinking about using a later model Gm wire box... I've seen it on a bunch of GMs. I'm just not sure if it is a junction, or meant to hold a fuse like that.

Thanks a lot everyone,
THe Swede
 

restomodracing

New Member
Feb 12, 2004
8
0
0
West Hills, CA
Feb 13, 2004
#2
  • Feb 13, 2004
  • #2
Based on the diagram, it doesn't look like you would use the regulator. It looks like you will hook the Alt Red wire to your ignition and the Alt output wire (Red Grommet) to the starter relay (battery side).

Personally I did not use the 3G, instead I used a one wire PowerMaster alt. So I'm not positive about the wiring.
 

67coupestang

Founding Member
May 31, 2002
509
2
19
Feb 13, 2004
#3
  • Feb 13, 2004
  • #3
yea no regulator the 3g is internal... it was pretty easy, but as for color to color differences between the stang and the bronco i have no idea... if i knew how to post i have a simplified drawing of the 3g in my 76 bronc...
 

67coupestang

Founding Member
May 31, 2002
509
2
19
Feb 13, 2004
#4
  • Feb 13, 2004
  • #4
there we go!
 

Swede958

Founding Member
Dec 17, 2001
712
0
0
Austin, TX
Feb 14, 2004
#5
  • Feb 14, 2004
  • #5
Forgive me y'all, I'm still a bit confused...

67coupestang: from the looks of it, you wired yours differently than the one on bcbronco's site. Instead of wiring the yellow wire to the B+ terminal you wired it to the starter solonoid... does it matter since both are theoreticaly under power all the time when the alt is spinning?

As for the rest of it, red (my orange) will go to the B+ terminal and the grn/red one to the solonoid.

sounds about right to me... oh yeah, one quick easy question for everyone. To re-clock and alternator, is the only thing you have to do it turn the case? I ask because instead of the voltage regulator exiting on the right of the alt (when viewed fromt he back) it is exiting straight up to the smaller mountin point. I will check at work tomorrow if this is corect but if it is, can I just rotate the rear case so that the regulator is facing the 'correct' direction?

Thanks again,
The Swede
 

67coupestang

Founding Member
May 31, 2002
509
2
19
Feb 14, 2004
#6
  • Feb 14, 2004
  • #6
wish i had the truck here to double check... the thick black wire going to the post on the back of the 3g i think was optional and something like if its there then your volt guage won't work anymore? the grey square represents a plug for the bronco.


as for clocking it that sounds right...
 
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