Topic: gm 3 wire... internally or externally regulated?

[toyotanner]

i have a gm 3 wire alternator that i got for free and i was wondering if theres a way to tell if its internally or externally regulated... it has a battery stud a ground stud and 2 prongs... i found a diagram on how to hook it up just don't know if its externally or internally regulated

thanks in advance for any info 

[possume22]

you got any pics of it

[toyotanner [OP]]

no... i was looking at pics of internally and externally regulated ones and i really couldn't see a difference... if i hooked it up like it was an internally regulated alternator  but it was externally would it still charge or would my volt meter go crazy

[ZUK]

You're talking about the ever so common 7127 model alternator? It's a 1 wire hook-up really....internally regulated also. Tie the F to the main heavy wire and run that to the battery....let the 3rd wire just hang.

[ZUK]

http://purplesagetradingpost.com/sumner/techinfo/onewire.html