Packard Forum Index » Pre-War (1899-1942)

Have 1940 with 356 engine. Amp gauge always shows full charging even when battery has been on charger and shows 100% charged. Concerned about over charging and ruining this new battery. Reading Packard owners manual it talks about adjustment to cutout relay in voltage regulator,anyone with experience on this?

Not enuf history given. Is this a problem that just started???? Was it working fine before????

At this point check the "F" wire on the generator to see if it is grounded directly to the generator frame or maybe grounded at the other end of the wire where it goes to the reg.

Thanks, just purchased this 1940 180 Packard and am going through it to make it road worthy. Noticed amp meter always showing fully charging. New battery and cables installed prior to purchase! F terminal is grounded to generator frame according to ohm meter. Also grounded to regulator base.

Hopefully you are reading thru a closed set of points and heavy wire. When in operation there should not be a direct or permanent ground on the field or F wire. I would verify that is the case. Normally the voltage relay in regulator will rapidly open and close shorting and adding resistance in the field circuit to regulate the generator output. If F is permanently grounded, then generator is putting out max voltage and things could get interesting.

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I should have been more detailed.

If the "F" terminal of generator isgrounded then that will cause FULL UNregulated output of generator and therefore full tilt amp readings at the amp gauge.

Grounding the "F" terminal is an old 'shade tree" trick to sidestep bad (usually incorrect) regulators or other malodies.

OF course the grounded "F" terminal needs to be corrected to allow for good regulation of gen output. Most likely a bad regulator or incorrect regulator.

HOWEVER, depending on a variety of conditions and situations allowing full generator output may not be all bad, just not most desireable. OR it could be bad. Depends on a variety circumstances under which the vehicle is used.

I have one application here that has "F" termianl grounded for over 18 years and running mostly sustained 2500 engine rpm for sometimes as long as 4 hours. No problems. About all it ever kicks out is 20 amps. Usually premature points burning will occur but not in this particular case of mine.

Maybe not a good excuse to continue running it that way but not a bad one eother.

Any regulator u get be sure it is the rite regulator for your application.

Also determine if the generator itself is correct for the car. There should be a tag on the gen with model numbers and soforth. So ordering a regulator for the car by model make and year mite be incorrect if generator has been swapped into the car from some other vehicle.

Thanks, great information. OK, do have correct regulator VRP-4003A and generator GEA-4802-A and they are wired as per your posted wiring diagram. Will be unable to run test until later this coming week as I am rebuilding leaking full pump and parts will not be here then. If I understand correctly, the grounding and un-grounding of the field at the regulator is what determines if the amperage is sent to the battery or directly to ground? Looking at the wiring diagram of this 1940 model 1806 noticed that the battery charges through the amp meter and depending on the charge level of the battery more or less current flow shows on the amp meter. What I don't quite get is the load which doesn't go through the starter input terminal, like the battery, takes off from the input terminal of the amp meter, how does this load (head lights etc) show as amperage flow across the amp meter?

The field will show continuity to ground as long as the brushes are in contact with the armatures commutator. I think the first and easiest check would be to disconnect the field wire at the regulator and see if the problem goes away. If it goes away, then that would indicate a problem with the regulator. If it still charges high, then the problem would be in the wiring or with the wiring inside the generator. Feel free to contact me with any questions. I have regulators available also.
Jason
Advanced Electrical Rebuilders
www.aerrebuild.com
jason@aerrebuild.com