Alternator conversion trouble.
I recently converted my 65 nova to a 10 si alternator and have been having problems that I am at a loss to explain. I Ran a 10 ga. wire to the pos. battery terminal, the sensing wire to the horn relay. I hooked the field terminal to switched 12 volts. I noticed that the alt. was overcharging so I think, bad reg. and replace the alt with a new one. Much to my dismay I find out that the new one is doing the same thing. It will sit there idling at 14.5 and then all of the sudden it will max out at 16-17 volts and start to boil the battery intermintently. On and off like there is a loose connection but unfortunately I have checked everything to no avail. The only thing that is questionable to me is the #1 field wire hook up which from my understanding doesnt do anything in my application anyway. The other thing is when I installed the alt. I used a cheap parts store pigtail which was shorting out the sensing wire against the case in both cases. I took the old one in to be tested and they said it was good?! I am wondering if alternators fail intermintently or not.