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MEXICOWANDERER's avatar
MEXICOWANDERER
Explorer
Jan 09, 2018

Replace Fire Hazard Ford 2-G Alternator With Better 3-G

This You-Tube video is an aid.

https://www.youtube.com/watch?v=_nhHk7TX3ws

  • Older alternator mid eighties to early nineties
  • High amp 2-G model offers 75 amps
  • High amp 3G small case model offers 95 amps
  • Large frame 3G offers 130 amps
  • Necessary to change fire-prone 2G plug to a 6 gauge 1/4" ring terminal
  • Correct voltage regulator is colored BLACK
  • Voltage regulator plug is identical and interchangeable
  • If arm with slot pivots, it is possible the large case 3G may drop right in
  • Changing from a 75 amp to the large 130 amp big case requires a larger battery feed wire
  • 6AWG cable will give optimum
  • The charging improvement at idle is phenomenal
  • The 3G uses longer brushes and much stouter bearings
  • Later model Ford alternators, the 4G and 6G are as good as the 3G but they have entirely different mounting points
  • New Ford parts, then remanufactured Ford parts offer excellent quality
  • Be sure to double check that your replacement alternator is the 95 amp small case or 130 amp large case model

2 Replies

  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Jan 10, 2018
    The 2G IAR alternator has a pair of "plug-ins". The voltage regulator has the little wires -- unplugit from the 2G and plug it into the 3G

    The plug in power cables are hard to believe. The plastic end and plug is cut off. The two wires are stripped. Then they are stuffed into a six gauge ring terminal that has a 1/4" hole, and then crimped or soldered.

    See the little white wire on the the power clip. If your alternator has this look below for the pigtail.



    3G STATOR PLUG PIGTAIL

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