Voltage Regualtor Diagnosis


New member
I recently cleaned the contacts and adjusted the regulator on my 63 Falcon. It was charging around 13V and the GEN light would flicker intermittently going down the road. It's the original regulator (or at least a FoMoCo) and the car sat for about 45 years so I figured it could do with a service.

Anyway, I adjusted the voltage up to 14.5V and it seemed great until winding it up in 2nd on the test drive the light came on bright and steady and didn't go off until I pulled in the driveway (about 1/2mi). I've moved it around the driveway since and it seems normal, GEN light dim at an idle and goes right out with any revs. Any ideas what's going on here?


Top Poster
Staff member
Supporter 2021
Supporter 2019
Congrats the fact that you got it to work and charge again means that it's likely still in reasonably good condistion. If the car sat for 45 years I think it's time to check out the condistion of the brushes in the Generator and also the commentator (that the brushes ride on) it may only need a good cleaning, or it might need to be re-machined to make it a clean flat surface again in that case it will also need new brushes so they seat good too. Cleaning can be done with sand paper or emery cloth or you can wait and see if it will clean itself up again. There is also a chance that the brushes are sticking in the holders and may need some cleaning up. I also just remembered something from my youth many decades ago. I remember seeing severial,old timers using a welders flat soap stone on the generator comintator I assum to clean a reseat the brushes you might see if that works too or look it up anyway. Good luck


Not too helpful but:
My '63 170 wagon sat for an indeterminate time. It had an odd vibration at engine speed that I traced to the Crank/WP/Generator belt trio. The generator's armature end shaft in the bushing had rusted and when re-animated had developed an egg/cam shape resulting in the thumping - rhythmic vibration...

.. '63 is @ 15 years on the road again and still using the OEM VR, the generator from my '61 Comet with a '71 Maverick 170 swap (with points ignition) ...



Well-known member
Along with the above checks; make sure the regulator mounting surface provides a good ground where it's bolted. Surface rust can cause erratic problems.