Alternator question

Alternator question

Thanks Del, the light blue wire with yellow tracer is is same as diagram below. Measured at ballast end and had 10.69V
Key on coil +ve 5.75V
Key on coil-ve 1.4V

The ballast HIGH side test? Should I do that with key in run?
Oh i took distributor out and gave it a "spin test", and it "beeped" with meter in "continuity" mode, so that's good.
I'll get back at it tomorrow.
I'm contemplating buying another VR as a spare anyway, but before I pull trigger with that, should I go the square back alternator route with newer style VR?
Is it that much of a benefit to do so?

67Dart273 said
The light blue is that your alternator field wire? If so that is WAY LOW

Ignition "run" power comes out of the bulkhead and branches off to feed the VR the ignition, the alternator field, and if equipped, electric choke, and maybe some smog doo-dads

THAT POINT should be very close to "same as battery" with key in "run" position.

So hook everything up. Without unhooking ANYTHING probe both sides of the ballast and see what is HIGHEST and post that here. Check that reading against the battery. IE if the battery is 12.6, that point of test should be VERY close, maybe 12

If lower, you have a problem in the path from battery getting to the ignition switch, and the "ignition run" wire coming back out through the bulkhead.

With the key in run, measure coil PLUS and coil NEG. PLUS should be 6V--10V or so, this varies with the coil type. Coil NEG should be real low perhaps 1V

Try jumpering a clip from battery to coil PLUS and see if it starts, fires, or at least has spark.