We usually find the wiring is backwards, even in a new harness. Run a hot wire to your FLD o the alt. You should see more voltage. that turn son the alt. Then dissconnect the VR, and jump the to outside wires together. This should also make the voltage jump. If it doesn't, you wound your problem. If it does, a new VR may be in order.

 

Well,
that's a pretty unique set of numbers. Before you go much further try CPR's suggestion. Which you've all ready done part of in your first post. You should be able to look at the wire color where it plugs into the voltage regulator. The white wire goes from the field terminal on the Voltage regulator to the field on the alternator.
White = field
Black-Red = ground
Black-Yellow = Battery positive.

If that is not the issue, then you'll need to get aVOM that reads actual voltage.
9, 10 an 11, tell us the condition of the main battery cables (and solenoid). You want to check those as well. This is the path the alternator uses to replenish the battery. The positive side actually goes from the alternator to the B+ lug of the solenoid, then to the battery. So you really don't have to go all the way to the starter for just checking the alternator, on the positive side.

 

This may be completely off the wall but, you guys got my head spinning. You say your alt and reg are working as autozone told you. Your wiring is new, leading me to believe that the problem is that there is no power to turn the reg "on". Check to see if you have power at the "I" term of the reg. with the key on.

 

Both the old and new wiring harnesses did not come with a wire in the I slot of the VR. For grins and giggles, I hooked a volt meter to the I terminal anyway and did not get a reading from it.

Adding a new hot wire from the battery to the FLD of the alternator caused the voltage to spike to 16 volts, in the same way jumping the F and A connections of the VR does.

I retested the steps outlined by Scott above and got voltage numbers:

1. 13.0
2. no reading
3. 12.8
4. 12.8
5. 12.4
6. 12.4
7. no reading

 

Yeah, the '66 didn't have a wire to the I terminal. However, Stepman makes a very good point. You do need to have B+ at the Green-Red wire at the Voltage regulator (Terminal S). with the key turned on.

Quick cheater test:disconnect the VR connector, start car. Jump the F and the S wires on the harness connector. This should cause the Alt to put out full amperage. If not, then there is an issue with the Green-Red circuit. This test assumes there are no other problems with the wiring or charging system.

Full test:

1). Disconnect the VR connector. Turn the key on. Postive meter lead on Green-Red wire. Negative on negative battery post. Should read full battery voltage.

2). Same test with VR connector plugged in. Should still read battery voltage.

If you don't get battery voltage in test one, then the problem is either the green-red wire, the connector at the fire wall, or under the dash, where the green red wire plugs into the black-green wire that comes off the key switch. Or possibly the ignition switch itself.
If battery voltage is present in test one, but drops in test two, then you need to clean up the all the connectors. If it still drops, I'd do a voltage drop test across the ignition switch.
The reason for this test is to ensure, the Green-Red wire circuit is your only problem.

Good thoughts Stepman, Hope this helps badreiling.

 

After tinkering around with this today, I decided to take out the VR and have Auto Zone give me a new one. I figured since the battery was replaced in the last two days and the alternator gave a full output when the terminals were jumped, the VR was the only piece of the puzzle that could be bad.

I came home with a new VR (at no cost...gotta love warranties) disconnected the negative battery terminal, mounted the new VR to ensure full grounding, connected the VR harness, then reconnected the battery terminal.

After starting the car I got ~14 volts. Tested with headlights, radio, turn signals, and blower motor. All is well now.

The one thing I found was the suggestion to disconnect the battery before replacing the VR. Must be something sensitive about the VR that can cause them to blow out if it's not grounded before connecting.

Thanks to everyone for the help.

Brandon

 

Congratulations!

That's a great charging voltage.