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- - Electric ? (https://67-72chevytrucks.com/vboard/showthread.php?t=188923)

I have a 71 gmc c2500 2wd 383 stroker, blah, blah, blah. AnywayI bought it and It was only puting out 10 to11.5 volts. So I got aload boss 135amp HO alternator, same problem. Well as I was cleaning it up and straightening wires and what not I found a loom with a connector the is the same shape as the one in the back of the alternator( all that was hooked up was one wire from the battery+. So I hooked the wires up to the alternator and wow what do you know 14.5 volts..... For a while then It would go to near 18volts to 12 volts then 10. Then at idle it wold go to 14.5 but as soon as you start to go again it goes back to the 10 to 12 volts. Now Im no electric genious at all. So can someone tell me whats wrong? I can try to answer any additional ?'s you have if you want. I just want to be able to run the electric fuel pump fans headlights and all the fun jazz without the voltage dropping to where the truck runs like crap and if I floor it , it dies. Help please.
Thanks
-Harlem

Sounds like maybe a voltage regulator problem, perhaps. Have you replaced it?
I believe there pretty cheap. Worth a shot.

Quote:

Originally Posted by ClemsonChevy

Sounds like maybe a voltage regulator problem, perhaps. Have you replaced it?
I believe there pretty cheap. Worth a shot.

Well new alternator, new voltage regulator still 10ish volts is all I can get out of it

Have you chased the wires out to see where they go? They more than likely have a bad connection at some point. Look on drivers side raditor support and see if they have by passed the voltage regulator as most have with a late model alternator. Check all there work and make sure they did it right.