Regulator brown wire gets hot when unplugged, when plugged in loses juice. Alternator and regulator has been checked they are all good. What else could be wrong. :sad:

if anyone can please have any ideas about this. it will start up and run but it will only run off the battery, it's not charging. i've asked all the electrical wirings experts i know and everyone is stumped. can't understand why the brown wire has juice until you plug in the exterior voltage resisitor. only thing lacking this restore project is getting this to work. it's a L79 327 375 horsepower. this is 1 66 nova ss. thanks again for any advice you can give me. Gary

In 1966 they were still using mechanical points in the voltage regulator to make and break the 36 amp maximum circuits. If you have not replaced the voltage regulator and had the alternator tested by a professional shop then you are guessing as to the nature of the problem. It works off a Whetstone Bridge where the voltage is balanced against a know resistance (so if the battery goes south all bets are off as well, as it will be too low to ever get the system to recharge correctly). They were temperamental and easily damaged by heat and humidity (that is why the factory transistorized the alternator at the soon as it transistorized the radio; to get a more reliable system).

My recommendation is unless you are going to trailer this car the rest of it’s life, ditch the mechanical voltage regulator and go with a modern one wire 105 Amp alternator. It bolts right up and the only wire you connect up is the battery terminal lead; simple safe and reliable.

Big Dave