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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Alternator

  • Thread starter Thread starter blue66tang
  • Start date Start date Oct 29, 2006

blue66tang

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Jan 20, 2001
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Medford, OR
Oct 29, 2006
#1
  • Oct 29, 2006
  • #1
I just wired up my alternator on an 89 5.0, and it doesnt seem to charge. It could be bad, but I just want to make sure that my wiring is right. it has 6 wires total. Ok lets see if i did this right. It has 2 black and orange wires, both go to the bat side of the starter relay. it has 2 white and black wires, these get connected together. It has one yellow and white wire, this one goes to the bat side of the starter relay. Finaly the last wire, green and red, goes to a run wire on the vehicle. Is this all right?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Oct 30, 2006
#2
  • Oct 30, 2006
  • #2
See this diagram for alternator info.

I wasn't sure what you meant about the stator wires. And for the switch wire (lt grn/red), be sure to run it through a bulb and resistor (wired in-parallel).

Good luck.
 

blue66tang

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Medford, OR
Oct 30, 2006
#3
  • Oct 30, 2006
  • #3
That looks identical to mine except i have 2 black and orange wires. The only thing i dont have is the light and the resistor. Could this be why it isnt charging? What kind of bulb is suposed to be used?
 

jrichker

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Oct 30, 2006
#4
  • Oct 30, 2006
  • #4
The light tells you that it isn't working properly and limits the current flow. The resistor is a safety bypass in case the light bulb burns out. I would recommend using a similar setup.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Oct 30, 2006
#5
  • Oct 30, 2006
  • #5
I agree. The way it appears to me is: the lack of the bulb and resistor in the switch-wiring could cause a short or otherwise damage the regulator when the alternator is not excited, but the key is on.

Good luck.
 

blue66tang

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Medford, OR
Oct 30, 2006
#6
  • Oct 30, 2006
  • #6
hmm so do you think this could be my chargine issue. I just got a new clutch line, so I should be able to drive it tomorrow and bring it to an ALT shop.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Oct 30, 2006
#7
  • Oct 30, 2006
  • #7
The regulator provides a ground path for the ignition wire (to illuminate the amp bulb or flow through the resistor) and then pulls the ground once the alt excites and reaches the min. output threshold.
Hitting the switch circuit with direct 12 volts could probably do some damage, but that is only conjecture on my behalf. Jrichker might have a better idea.

Good luck.
 

blue66tang

Founding Member
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Medford, OR
Nov 1, 2006
#8
  • Nov 1, 2006
  • #8
Well I went down to Napa and had the alt tested. Their testing computer woudnt even start testing it, it would just just off. So something was deffinately wrong with the alt. So i got a new one stuck it on and it works great now. I also did put a 500 ohm resistor in that line. I hope everyting is good now. Thanks
 

HISSIN50

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15 Year Member
Nov 29, 1999
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#9
  • Nov 1, 2006
  • #9
Glad to hear it's up and running.
 

blue66tang

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Medford, OR
Nov 1, 2006
#10
  • Nov 1, 2006
  • #10
Thanks, but now i have to wait for it to get back form the exauhst shop. I am having 2.5" tubing with a set of flowmasters put on it. I hope it sounds good, but i have a feeling its going to be to loud for me. I like a nice quiet ride, if i want loud i can just drive my 66 mustang (see sig).
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
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#11
  • Nov 1, 2006
  • #11
I'm sure it'll be well-liked or you'll get used to it.

Enjoy.
 
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