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3g Alternator ?

  • Thread starter Thread starter Sulli88GT
  • Start date Start date Apr 29, 2017

Sulli88GT

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Apr 29, 2017
#1
  • Apr 29, 2017
  • #1
88 GT convertible. I'm doing the 3G alternator upgrade and I a little confused on the two black/orange wires. Some say unhook them and some say leave them hook up with the new 4g wire and the direction say to hook them up two, there is the connectors in the kit too. The complete kit came from LMR. And I did nothing the D plug location is at about 3-4 o'clock position instead of the 8 or so position. Any ideas on this would be great just want to do it right. Thanks
 

Grn92LX

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#2
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  • #2
Leave them unhooked. I just put great shrink over them. Its a potential fire hazard, too much amperage through too small a wire. Thats why you upgrade to the 4g
 

Sulli88GT

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Apr 29, 2017
#3
  • Apr 29, 2017
  • #3
Unplug at Alternator at union shrink and tape and leave plug at starter solenoid?
 

General karthief

wonder how much it would cost to ship you a pair
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#4
  • Apr 29, 2017
  • #4
http://www.stangnet.com/mustang-forums/resources/3g-alternator-fox-upgrade.18/


I think this has everything you need to know thanks to a guy named Dan.
 

jrichker

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Here is the reasoning behind using only a single 4 gauge fused power feed to the alternator. If you use the two 10 gauge black/orange wires in addition to the 4 gauge wire, you have two fused power feed paths. The total current capacity of the wiring is the sum of the fused paths. The 4 gauge path is fused for 125 amps, and the two 10 gages wires are fused for 60 amps. That is a total of 185 amps, which exceeds the capacity of the alternator. Overload can occur without the fuses blowing, damaging the alternator.

The worst case scenario is that the alternator develops an internal short to ground resulting in a catastrophic failure. The initial short circuit surge current is limited by the resistance of the wiring. The current in a parallel circuit divides up according to the resistance of the branches. If the 4 gauge fuse opens up first, the two 10 gauge black/orange wires will be carrying the short circuit surge current. Depending on the time lag of the fuse links, they may open up before a fire starts or they may not.


http://www.stangnet.com/mustang-forums/threads/3g-alternator-install-a-how-to.646825/#post-6673702

Alternator wiring.






If you have a 3G alternator, the white/ yellow wire is critical to proper operation. It is the voltage sense and regulator power lead that picks up the difference in voltage at the alternator output stud and the connection point at the starter solenoid. If you cheat and run it directly to the alternator output, it sees the voltage at the alternator output stud. It does not see the voltage at the starter solenoid connection point where it feeds power to everything else. You may have a voltage drop in the wiring between the alternator output stud and the connection to the starter solenoid. Thus you may have low voltage or less than the standard regulated voltage at the starter solenoid connection point. This makes for low voltage throughout the rest of the car: everything operates at less than full efficiency.

Starter solenoid wiring 86-91 model cars.

Connect the fused 4 gauge wire to the alternator and the battery side of the starter solenoid.


Starter solenoid wiring 92-93 model cars.
 
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