Very Confused!
Ok,
So the alternator gauge is a little twitchy. Like Del said it should read a little above at startup and settle to the middle after a few seconds.
It goes up a little but then settles into a jumpy twitchy type rhythm in the middle.
So if I understand correctly, when the voltage readings were 16.8 to 16.9, the engine was at slow idle, and the ammeter was showing just a little charging on and off?
@Mattax Every connection including grounds must be clean with little or no resistance. THe battery must be fully charged (it is) and fully tested. A voltage reading is only a start. Voltage drop tests and resistance to ground needs to be tested. Hopefully Mattax will help us out here.
I'll try Mike. Hopefully website doesn't crash my computer.
Based on Clementine's voltage measurements, I too would suspect the regulator is full fielding the rotor.
What throws me is the voltage should follow rpm up, and the battery should be getting overcharged (Point toward C on the ammeter).
One reason it may not show overcharge would be damage to battery feed - thus restricting the current the battery would otherwise take.
Where to start?
If it was me, I'd get the alternator and check it out. -> Field current draw test and check for shorts and opens.
You know I don't like these new rebuilt alternators which draw 5 to 7 amps.
But I don't think that's the reason the voltage is high. Although it may have been a contributor to the problem.
I'd pop the cover of the regulator and see if see if the points are stuck.
Or if its a transistorized version, change it out. Hate to say that, but that's a quick check. Before doing that, could disconnect the ignition feed to the regulator (don't let the connector touch ground!!). That should kill the alternator field. If not there is a cross wire issue. I just doubt that on a '67