Intermittent Charging Problem???

[SprayPaint]

Hey Guys,

My 1967 C20 has an intermittent charging problem. I start the engine once, and it’s charging. Turn it off and restart, and its not. Retry a few times later, it’s charging again, and so on.

I have replaced the alternator, battery, battery cables and grounding cables as well as continuity checks on the alternator harness. I’ve even run a separate ground wire from the battery to the regulator to make sure it has a good ground. When I install a brand new regulator it won’t charge at all. I put the old regulator back on, and it charges for a while, then not. I’ve heard something about polarizing the regulator but the new one did not come with any instructions on how to do that.

I’m out of ideas and at my wits end with it. Please let me know if anyone has any ideas. The truck is new to me as well as this board. I’ve enjoyed reading so many other great suggestions from you all. My hope is that you can help me on this one.

Thanks!