Packard Forum Index » Post-War (1946-54)

I disconnected the wires to the generator to install a new fan belt.

It does not appear to be charging when looking at the ammeter at a rev. Of the engine

Do I need to polarize the generator, jumper wire from arm to field on the voltage regulator?

Can I test first at the voltage regulator with a volt meter?

By the way, the fan belt listed for my car in the Parts Cross Reference on this forum was short enough so that now I have 2-3 inches to tighten the belt when necessary. The belt was Napa #24489.

Did you clean the connections before screwing them back on?

As long as they are reattached properly, I don't see any reason other than that why it should not work if it did before.

Quote:
Agreed, repolarizing is usually not necessary if it was only a wire disconnection. If you do try repolarizing it will not hurt anything but be sure the jumper is used to briefly short between ARM (or GEN) to BAT. Do not connect anything to the FIELD terminal except the wire going to the generator..

Oh, another possibility is your belt is too loose. But it should charge at least some, and it's not hard to get the tension right. I believe they suggest a ½" deflection under thumb pressure.

Another possibility was that when the wires were disconnected, they shorted against something, possibly damaging the regulator.

Sounds like you better determine for sure that your system isn't charging, that is, maybe it's just fine. You could simply put a volt meter on your battery and see how many volts it is. Start your car and see what happens when you rev the engine, the voltage should increase. You can turn on your lights as well to see what happens and then rev your engine and see if the voltage increases.

If your battery's voltage is only decreasing and not increasing then start looking for the issue. Lots of good suggestions already made. Maybe your wires got mixed up when you put them back on the generator? If they are original, maybe one broke?

I found there were quite a few good videos on YouTube for checking 6 v generators and charging systems.

After I had my generator rebuilt a year and a half ago I had to repolarize my car several times, not sure why I had to do it more than once. The charging system has been problem free for over a year.

Let us know what you find!

This is what I’ve tried after watching You Tube videos.

Cable directly from field on the regulator to field on the generator, no help
Cable from arm on regulator to arm on generator, no help.

Volt meter on both battery terminals, voltage didn’t increase when revved., both normal and with headlights on

Battery was fully charged using a Maintainer.

Removed the ground cable from battery terminal (positive) with the car gunning, car stalled.

Tried an extra jumper cable from positive terminal to ground on the body, no help

Polarized generator with jumper wire from arm to battery with car off. Sparked but no help.

Next step?

Remove the fan belt (very important). Disconnect the arm and field wires from the generator. Using an alligator wire or spare jumper wire, connect arm to field on the generator. Then connect the negative side (ungrounded side) of the battery to this arm/field circuit. The generator should spin in the direction of the engine rotation (clockwise). It will only spin at a brisk speed, but should get up to speed quickly.

Edit: field should be grounded not connected to power. Had it backwards.

Hybrid, can you give me a little more detail on this test. I watched several versions on You Tube but I’m still not sure how to do it.
Jumper from arm to field and then what?

This whole thing started with my wanting to replace the fan belt, so I know how to take it back off.
I have to move the oil filter out of the way (up) because the supply lines prevent the generator from rotating closer to the block. It’s a big job.

- Remove the fan belt (very important).
- Disconnect the arm and field wires from the generator.
- Using an alligator wire or spare jumper wire, connect arm to field on the generator.
- Then connect the negative side (ungrounded side) of the battery to this arm/field circuit.

Please let me know which step you are not sure on.

What we are doing is energizing the field circuit, which forms a magnetic field in the stator. At the same time we power the armature, which due to the magnetic field present, makes the generator spin like a motor.

Edit: field should be grounded not connected to power. Had it backwards.

Your car is positive ground, so the negative side of the battery is the "hot" side. The positive side is already connected to the generator via the case and chassis.