3G Alternator upgrade - Questions?

[fairlaniac]

I’m getting everything together to perform the 3G 130A alternator swap on my Fairlane (shouldn’t be any different that on a Mustang) I went to put my original single groove pulley on the 3G alternator and the first thing was the pulley bottomed out against the aluminum housing of the alternator and if I would have tightened the nut it probably would not have even moved. I took a .030” thick shim (washer) and put that under the pulley and it kept it off the housing and spun freely. Putting the nut on the 3G shaft with pulley installed only showed about 4-5 exposed threads. I put the nut on and torqued it but the shaft end is still about 2-3 threads under the nut? I’m sure others have run across this, as I don’t have any special 3G alternator or pulley. 3G is from a Taurus.
I’m also noticing that the 3G is about one half inch wider (front to back) that my original alternator. The back of the alternator is against the head. My engine is a 390 and it should not matter if it is Fairlane or Mustang as the mounting on a 390 is about the same and using the same parts. Are there any tricks that I’m missing to fit the alternator in the same gap that he original alternator resided in?

Thanks,
Doug

 

[rsev216]

I used the 3G from a 95 Mustang GT because that was what most recommended. I had no problem with the pulley hitting the case although it is close and there were plenty of threads. The only trick was shimming the alternator to get perfect pulley alignment. If the pulleys are off even slightly the belt squeals.

The attached documents indicates that there are some differences between the Taurus and the Mustang 3Gs.

 

[rsev216]

The attachment was too large to post.

 

[Tim65GT]

From the info I gathered before I did my swap, there is a Large case 3G and a Small Case 3G. I got mine off a '94 Mustang GT. And it bolted right on, I also used a two groove pulley from my old Alt.

It sounds like you may have the large case type and maybe the shaft is different.

 

[68keyblr]

I used the 3G from a 95 Mustang GT because that was what most recommended. I had no problem with the pulley hitting the case although it is close and there were plenty of threads. The only trick was shimming the alternator to get perfect pulley alignment. If the pulleys are off even slightly the belt squeals.

The attached documents indicates that there are some differences between the Taurus and the Mustang 3Gs.

Yo Rsev, when are you coming over to do my 3G conversion???

 

[rsev216]

You will have to schedule a time on my calendar. I am teaching a class through the 27th and I'm busy every Wednesday through March 9.

crapola