View Full Version : 3G alternator upgrade

m j
11-26-2006, 06:42 PM
Ok I got the 3g installed in my 1978 bronco

For the ammeter wiring I ran the yellow with black stripe wire to the B post on the alt and the red with orange stripe wire to the starter relay post.
That should give it a run between the 2 similar to the factory 1978 wiring.

I also ran the yellow S wire to the starter relay post rather then to the alternator B post mimicking the factory wiring.
Theory is to give it a truer Battery voltage reading.

I reused the fusible link, which was running from the starter relay to the B post on the alternator, as a fuse for the ign feed (black with yellow stripe wire)

The 175amp fuse from the Taurus gets mounted directly to the starter relay post and the B wire gets bolted to the other side of it.

Did the install in a snowstorm on a Sunday so I still have some odds and ends to clean up i.e. shorten the B wire to make it look cleaner.

The sheave spacing got me for a bit until I noticed a thin spacer on the old alternator under the fan, once that was in place the sheave interference issue was resolved.
Without the thin spacer the sheave from the old 1g alternator was contacting the 3g case.
I ground a spare sheave to reduce the case interference but the front bearing on the 3g didnít really match the OD of the sheave that is supposed to ride against the bearing.
Once the spacer was found it all worked as it should.

My paint job on the alternator didn't go as well as I liked due to the cold temperature not letting the paint dry as quickly as my patience ran out.


*edit- some stuff works in ADVANCED MODE editing but still no copy paste on the original post. at least I got to edit some :) -*

11-26-2006, 08:52 PM
Can you explain what the difference is between the alt that came originally and a "3G" alternator as I've heard this a few times and don't know what the difference is. Thanks[cheers]

m j
11-26-2006, 09:32 PM
3g I think means 3rd generation
the 3g has an internal regulator vs an external regulator. I do not think that is a real advantage in placement but it is also more modern design and style with brushes easily accessed and changeable.
the 3g has 2 internal fans, one front and one rear, rather then one front external fan on the 1g.
the stock 135amp 3g outputs more amps at idle then the old 60amp 1g did at full rpm.
plentiful in wrecking yards under the hood of 95 taurus if you want a used one.

m j
11-26-2006, 09:35 PM
hey the edit worked on the reply post, still hanging on the origonal post???


11-27-2006, 08:24 AM
Thanks. Now to do some more research. I work in an automotive shop and in my listings for someone I was looking for parts for, it actually states that a certain brand of alternator was a 3G, which what they were looking for, however, I wasn't sure what it meant. I can check on the regulator also to see if it is external or internal (I think it's internal) on the one listed. :)