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Discussion Starter · #1 ·
To check output voltage of alternator with voltage regulator bypassed:

On a 67, disconnect the harness from the regulator. Connect a jumper
wire inside the harness between the white & yellow wires. Start the
car and check the voltage reading at the battery. It should be at about
15 volts or more. If it is, there's a problem within the voltage
regulator or the regulator wiring (I would look for a bad ground at the
regulator). If the voltage isn't high like that, there's a problem with
the alternator.

What you're doing in this test is bypassing the voltage regulator (I'm
sure you figured that out already) to check the true output of the

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Discussion Starter · #2 ·
I believe what this does is direct full battery voltage normally going to the "A" terminal on the VR to the wire coming from the field terminal on the alternator which would normally be connected to the "F" terminal on the VR. Providing maximum excitation to the alternator field results in maximum generation of power. Only want to do this momentarily. This test assumes good continuity of the wire going from the connector to the FLD terminal on the alternator.
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