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  • 1965 - 1973 Classic Mustangs -General/Talk-
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Need help

  • Thread starter Thread starter suki243
  • Start date Start date Aug 18, 2007
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Aug 18, 2007
#1
  • Aug 18, 2007
  • #1
Hey guys,
before I went on vacation I got the car back from paint. I then decided to replace the only set of wires that I hadn't replaced yet... The wires that go from the Voltage Regulator to the Alternator. I thought I replaced them perfectly but I was wrong. I need your help in finding out what I did wrong.

My steps:
1. disconnect battery, use an ohm meter to find out the start and end of each wire from voltage regulator to alternator.
2. Pull out old wires
3. Replace with new wires
4. Fix the one wire leading to the ground on the engine block, the wires were frayed and exposed.
5. Hook it up.

A few times I was able to get a single click... Other times I get absolutely nothing.

Need some help trouble shooting... I may have connected the wrong wires... I have no idea what I did wrong.

I have the stock alternator and the voltage regulator has 4 terminals on it. The alternator only had 3 wires from the start coming out of it. One of which was a ground. Another has the word Bat labeled on it. The last one I have no idea where it connects to. There was also a set of wires connecting to one of the terminals on the starter solenoid, but after replacing the old wiring harness I simply put a bunch of electrical tape around that wire and it was able to run fine. so I didn't include it in the new bunch of wires.

It may also help to mention that there is a bunch of wires that looks like it is going to the front right headlight, and I simply cut off the wires going to the headlight cause they connected to the ones going to the voltage regulator.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Aug 18, 2007
#2
  • Aug 18, 2007
  • #2
check out the wiring diagrams here. this shows the conversion from a generator to an alternator. http://www.mustangsteve.com/GENtoALT.html
 
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Aug 19, 2007
#3
  • Aug 19, 2007
  • #3
Thanks, I'll try it out tomorrow, How do you know which terminal is which? I know the batt terminal is there, but i dunno about the STA and the Fld terminals are on the alternator.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Aug 19, 2007
#4
  • Aug 19, 2007
  • #4
the terminals should be marked on the housing.
 
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Aug 19, 2007
#5
  • Aug 19, 2007
  • #5
hmm k, but originally i can promise you I didn't have a wire going to the Fld, but i guess i'll try it now and do it the right way.
And ez wiring's harness has a white wire that connects to the regulator at the I terminal, and the alternator at the Bat terminal what should i do about that/
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Aug 19, 2007
#6
  • Aug 19, 2007
  • #6
suki243 said:
hmm k, but originally i can promise you I didn't have a wire going to the Fld, but i guess i'll try it now and do it the right way.
And ez wiring's harness has a white wire that connects to the regulator at the I terminal, and the alternator at the Bat terminal what should i do about that/
Click to expand...

the I terminal on the regulator goes to the indicator lamp to let you know when the alternator is not charging. i dont know what to tell you about the other white wire. in this case i would contact ez, and see what their tech support says.
 
S

suki243

Member
Dec 19, 2006
662
0
19
Southern California
Aug 19, 2007
#7
  • Aug 19, 2007
  • #7
I got it down, thanks rbohm; I'm not sure what the alt excitor wire that they have in the harness does, but there was another wire coming form the harness to the alternator called alt power, i just spliced the wire with another one leading to teh a, rant he sta and field wires and it would do a quick turn and then stop... then I looked at teh voltage regulator... looked at it and i noticed that the A and the S had an extra wire coming out of em, (previous owner) one is the female bullet and the other was just a wire, I put electrical tape around em, tried to start her up, she was turning weakly, but i pumped gas twice, and held key there and vroom!!! sputtered and then stayed strong. It was a sigh of relief! I just have to get another color wire and run it underneath the radiator support to finalize the wiring, I had temporarily ran one for now.
 
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