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86 Alternator In 85 Mustang

  • Thread starter Thread starter TRIBUNAL
  • Start date Start date Aug 12, 2008
T

TRIBUNAL

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Jun 12, 2005
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Aug 12, 2008
#1
  • Aug 12, 2008
  • #1
I got a new 86 alternator today for my project car, turnes out the 85 wires are what i have, not the 86 harness.
Can i get this to work?
There's two spots on the new alternator for wires to be connected
 

jrichker

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Aug 12, 2008
#2
  • Aug 12, 2008
  • #2
All I can find are the 3G install instructions. They are the same with the exception of adding the 4 gauge fused power lead.


Tech note courtesy of SwAmPf0x:
How to wire a 3G in an 85 or earlier Mustang
cut and paste from an old post of mine...

There are 4 wires to the voltage regulator, cut the plug off the regulator, extend the 2 wires used to the alt and cap off the other 2

The F will not be used.
The I will not be used.
The S will go to the 3G
The A will go to the 3G

wiring on the 3g side

The Big post on the back goes to the solenoid, same side as the battery, a fuse is recommended on this wire, also up the wire size to 4ga minimum

Now for the 3 wire plug...wires A,S,I

A goes to A from the old external regulator
S goes to the stator connector on the 3G
I goes to S from the old external regulator
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