100A Alt Swap Question

[ettev]

Just got done doing the Hitachi-toGM alt swap as described here: http://random.removed.us/altswap.html

 

The alternator I got was off a 1982 Caddy. Here's my question. One of the two wires (the field signal wire) from the caddy's two pronged plug was tied back onto the output stud. Why did they do that? When I tie into my wiring harness does it make a difference if I simply eliminate that re-feed and go directly to my field signal wire, or should I leave that GM wire tie back into the output stud and splice my field wire into that?

 

I test ran it without the wire looped back into the stud and it seems to be charging steady at 14+ volts.

[GeneralDisorder]

One of the two wires (the field signal wire) from the caddy's two pronged plug was tied back onto the output stud. Why did they do that? When I tie into my wiring harness does it make a difference if I simply eliminate that re-feed and go directly to my field signal wire, or should I leave that GM wire tie back into the output stud and splice my field wire into that?

 

They did that to eliminate the field circuit (and the charge indicator lamp). By tying it back into the output they made the alt self-exciting (the output see's 12v from the battery when the alt is not making power). This way they didn't have to rev the engine past 3k to get the alt to self-excite.

 

GD