Hey all. I guess a couple months ago or so I posted this thread:
http://67-72chevytrucks.com/vboard/showthread.php?t=214256

I "fixed" the trucks issue of not starting hot by cleaning all the wires and all the grounds for the alt, battery, and starter.

Got a new problem now?

I added an aftermarket volt meter to the truck a couple years ago. The truck charged right around 14, just like it should. A few weeks ago it started acting up. One time I start it, it would run as high as 16 to 18 volts, so I turned the headlights on and it would drop to 14-16. Then the next time I start it, the truck would only show 10-11 volts charging. When it shows this, the truck has a hard time starting (slow crank, like a dying battery), but will still fire.

This has me totally baffled, I never know which condition will occur (over or under charging) when I start it. It happens randomly as to which it will be???

I've had the alternator tested, and it came out good (but I don't really trust autozone anyway) and I replaced my voltage regulator about 6 months ago. All of the connections have been cleaned and all grounds are on the truck...

Sorry for the long post, but does anyone have any ideas?

sounds like a bum import regulator.
I would upgrade to an internally regulated unit myself.

I agree with Longhorn Man, as easy as it is to upgrade, and with as much trouble as the external regulators have given me in the past, this is one of the first things I always do to these trucks (and go to hei ignition)

Try banging on the regulator when it is giving you trouble, if it changes the output then you will know it is bad...


Rg

Do y'all mean to get rid of the voltage box and get an internally regulated alternator? That's that conversion in the FAQ right? If I were to do that, what vehicle would I buy an alternator from?

The link in the FAQ mentions a couple of different ones you can use.

Rg

Ooops, should have gave some background info. My truck is a late 70's engine with the alternator on the PS and it has a "long" water pump.... I have the brackets off of a 72 Chevy for the DS, can I make this work with the long water pump, and how? If not, I plan to add A/C so I might have to hit up a junkyard.