Burnt Contacts on Voltage Regulator

[41SupDelux]

Good evening, folks,

Mistakenly posted this in the wrong forum to begin with - Oops.

1941 Ford Super Deluxe.

I was curious what your opinions might be on my voltage regulator. I had been having some charging issues and went about testing a few different parts of the electrical system, which is 6v, fyi. Took the generator off and found a broken brush spring; replaced that and bench tested it (hooked it up to power to get it to motor - worked). A-meter showed charging, but then a couple days later, stopped. Took the voltage regulator off to inspect contacts and saw that the contact points had burn marks on them. I had the cover off and figure maybe I got some oil from my hands on them or dust got in there. Car is running off battery - I found this out when I had trouble driving it at night with my lights on. (Dust is suspect because we just finished harvest... So it has been dusty, to put it mildly.) Is this repairable or do I need to replace the unit? It's a shame, because this is a US made unit that has presumably been on here since its restoration in '83-'85.

[Bill OH]

Clean contacts with very fine sand paper, polarize field by touching field wire disconnected at regulator to Bat terminal on regulator, using analog voltmeter adjust field control with engine running at 1500 rpm to 7.2 volts, clean connections on generator and regulator with sand paper, run 16ga wire between frames of generator and regulator to achieve zero ohms with digital ohmmeter and put cover on regulator - keep out the dust. Try all of that - report back.

[J Franklin]

Maybe you can still buy a points file somewhere. They are better than sandpaper.

[Kurt in NJ]

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With the cover off you can watch the cutout close if the generator is charging — the cutout relay is the one with the contacts on the top— and in your picture a loose part is laying on the cutout arm., the center one is the amperage regulator, the one cutoff in the picture is the voltage regulation element.
If you close the cutout contact with your finger with the belt off the generator should “motor” and power should go the the field terminal (use meter or text light)— it will be polarizing the generator at the same time.
A metal nail file with fine grit can work to clean contacts, sand paper can leave non conducive grit behind that would have to be removed .
If you watch the regulator in the dark as the engine is brought over idle the cutout contacts should close, the voltage climbs as rpm increases and when it goes over the voltage regulating limits there should be a slight arcing of the voltage regulating contacts, if the generator current regulating (amps) limit is exceeded (all electrical consumers on)the center relay contacts should have small arcing as it limits output to protect generator from burning up from working too hard.
Any adjustments to the regulator have to be rechecked after the cover is put back and the internal temperature has stabilized.
Most any Motors auto repair book between late 30s and early 60s should have a section on adjusting the regulator in detail