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Replacing 2g Alternator 87 Mustang Gt Need Help!!

  • Thread starter Thread starter Assassin 5.0
  • Start date Start date Dec 19, 2014
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Assassin 5.0

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Jan 11, 2015
#21
  • Jan 11, 2015
  • #21
Ok... So I decided to go with the 6g alternator for various reason. Picked up a cheap reman off eBay for $69.99.. now before I begin install I had a few questions:

1. Some people are using various type of fuse rating for their setup... Some use 130amp fuses some use 150amp fuses and most use a 200amp fuse. Is 200amp fuse the way to go?

2. Is anyone using a 12V DC breaker instead of a fuse for the 4ga power wire to the batt? I have a 200amp breaker but wanted to get thoughts on using a breaker vs. a fuse before I install it

3. Some write ups have different thins to do with the " now unused" stator wire being that the 6g setup does not use it ... Some say to loop it , some say just cap and tape it off..Which one is correct?

Thanks..
 

jrichker

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#22
  • Jan 11, 2015
  • #22
Facts:
1,) The wire size must match alternator output as closely as possible. Larger wire size is OK, avoid smaller wire size.
2.) The fuse or circuit breaker must closely match wire size, no matter what size alternator you have. The fuse or circuit breaker protects the wire from burning up and burning your car to a smoldering heap.
DO NOT OVERSIZE THE FUSE OR CIRCUIT BREAKER!!!!

If you use a 4 gauge wire, use a 125 amp fuse or circuit breaker. Both high current fuses and circuit breakers have a 5%-10% continuous overload capacity and usually a 150% short time overload as part of their characteristics.

 

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Last edited: Jan 11, 2015
A

Assassin 5.0

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Jan 16, 2015
#23
  • Jan 16, 2015
  • #23
change of plans again....sourced a 3g alternator reman for $50.00. just gonna use it. now do i have to swap the pulley off of my old 2G onto this 3G alternator or can i just use the one already installed?
 

Shakerhood

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#24
  • Jan 16, 2015
  • #24
3G Pulley works fine on my car, you will have to check on your car.
 
A

Assassin 5.0

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Jan 17, 2015
#25
  • Jan 17, 2015
  • #25
ok...what exactly should i be checking for?.... from what it looks like the pulley on the 2g and the 3g seem to have the same amout of grooves correct? im using the stock pulleys on everything else as far as the p/s , crank , a/c and smog so with that being said am i just looking for clearance issues or something?
 

mikestang63

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Jan 17, 2015
#26
  • Jan 17, 2015
  • #26
3g pulley is larger in diameter which equates to less charging at idle. Swap your old 2g pulley on it and use red loctite on the nut. Takes 30 seconds with an air gun.
 

Shakerhood

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#27
  • Jan 17, 2015
  • #27
Yep exactly, it may not put out enough at idle.
 
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