'47 Charging sytem

[don-wi]

I need to know how to full field the regulator to see if my generator is working or if I have a bad regulator. Last weekend I noticed that the car was not charging very much. I tested the battery and it shows 6.22 volts with the car not running. When I start the car it shows 6.07 volts and if I turn the headlights on to load the system it drops to 6.03 volts. It is stock, 6 volt with positive ground. I looked at the Powermaster alternator that looks like a generator over the weekend and not sure if that is the way I want to go. I know many guys put a GM one wire alternator on, I'm sure they work but it sure looks out of place when the hood goes up.
Thanks
Don

[oldskool]

you ground the field wire at generator or regulator.if it charges you have a bad regulator if it doesn't you have a bad generator,also check and clean ground wire at regulator

[koates]

Hi there, On a 47 ford generator you would disconnect the field wire at the voltage regulator and connect it onto the ARM (Armature ) terminal of the regulator. Rev engine up some and cut out contacts should close and generator will charge flatout if it is OK. If the cutout contacts don't close and no charge then the generator is most likely faulty. Grounding the field is not correct for this ford. Usually on GM cars and some others with Delco equipment the field is grounded to do this test. Regards, Kevin.

[don-wi]

Can a jumper wire be used to jump the A terminal with the F terminal or should the wire on the F terminal be removed and put on the A terminal? Thanks Don

[Old Henry]

I just went through this with my stock 47 charging system that gave out 200 miles from home on our road trip last weekend. I disconnected the wire from the armature of the generator to the armature terminal on the regulator then jumped current directly to the field terminal on the generator and put a test light on the armature terminal of the generator. The current directly to the generator field should have made it charge and light up the test light on the armature terminal but it didn't. So, most likely the brushes on the generator need replaced. I finally figured out that test after replacing the regulator that I initially suspected which is probably OK since it's the generator that's not charging.

[koates]

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Hi again, better to remove the field wire from its terminal on the v/reg and connect it over to the ARM terminal. Don't use the jumper wire. Regards, Kevin.

[don-wi]

I removed the field wire from the voltage regulator and put it to the ARM terminal, I checked the voltage at the battery with the car idling and it was 6.5 or so and as I raised the idle it went up to 7.7 volts. I'm sure the regulator is the problem now. I'm thinking maybe take the cover off the regulator and check the contacts, maybe I can see the problem. I'm looking into converting to an alternator but maybe can get things to function until I get everything ready to make the switch. Thanks Don

[Old Henry]

Originally Posted by Old Henry

I just went through this with my stock 47 charging system that gave out 200 miles from home on our road trip last weekend. I disconnected the wire from the armature of the generator to the armature terminal on the regulator then jumped current directly to the field terminal on the generator and put a test light on the armature terminal of the generator. The current directly to the generator field should have made it charge and light up the test light on the armature terminal but it didn't. So, most likely the brushes on the generator need replaced. I finally figured out that test after replacing the regulator that I initially suspected which is probably OK since it's the generator that's not charging.

Sure enough. It was one of my generator brushes worn out. Don't know why only one wears out but that's how they wear. I was a little surprised though since I just rebuilt this generator with a new armature and brushes back in September, a mere 13,000 miles ago. I would have thought generator brushes would last longer than that. I'm going to put some spares in my trunk with all of the other spare parts possibly needed on a road trip just in case I need them. It's amazing how far I have gone without a generator during the day with nothing drawing on the battery except the coil, the last 250 miles of our Route 66 trip and the last 200 miles of our last one with still plenty of juice to start the engine.