The Ford Barn

smittykid · 08-18-2017, 05:36 PM

Long story short, I moved the third brush quite a ways up on the armature to reduce the output. I also replaced the stock cut out with a NUREX diode cut out. The system is still 6 volt pos. ground. After adjusting the 3rd brush-it reads 2 to 3 amps at idle and about 10 amps at fast idle or about 40 mph. I'm being told that is still to high a charge rate. How far can you move that 3rd brush up? When I turn the lights on at fast idle the amp meter goes down to 0-1 amp. Now what?

J Franklin · 08-18-2017, 07:01 PM

10 amps may or may not be too high depending on how much driving you do with the lights on. You just don't want to boil all the water out of the battery by overcharging. To find out about the third brush set it both ways fully and make a comparison and the report back here for others. If you are really worried buy a voltage regulator made for the Model A.

RonC · 08-18-2017, 07:43 PM

Daytime driving 3 amps isplenty

Kurt in NJ · 08-18-2017, 07:47 PM

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I have had the charge rate set at 14 amps for the last 20 years, I also have a diode cutout, when I go on a long drive I turn the lights on for a while, have always had long battery life, got 16 years out of the Optima
If I was to go on a very long trip I would set it back to 6-10

08-18-2017, 05:36 PM	#1
smittykid Senior Member Join Date: Jul 2014 Location: NW Pa./Sc. Posts: 252	How far can you adjust the generator 3rd brush? Long story short, I moved the third brush quite a ways up on the armature to reduce the output. I also replaced the stock cut out with a NUREX diode cut out. The system is still 6 volt pos. ground. After adjusting the 3rd brush-it reads 2 to 3 amps at idle and about 10 amps at fast idle or about 40 mph. I'm being told that is still to high a charge rate. How far can you move that 3rd brush up? When I turn the lights on at fast idle the amp meter goes down to 0-1 amp. Now what?

08-18-2017, 07:01 PM	#2
J Franklin Senior Member Join Date: May 2010 Location: Oregon Posts: 5,962	Re: How far can you adjust the generator 3rd brush? 10 amps may or may not be too high depending on how much driving you do with the lights on. You just don't want to boil all the water out of the battery by overcharging. To find out about the third brush set it both ways fully and make a comparison and the report back here for others. If you are really worried buy a voltage regulator made for the Model A.

08-18-2017, 07:43 PM	#3
RonC Senior Member Join Date: May 2010 Location: Rhode Island Posts: 1,868	Re: How far can you adjust the generator 3rd brush? Daytime driving 3 amps isplenty

08-18-2017, 07:47 PM	#4
Kurt in NJ Senior Member Join Date: May 2010 Location: on the Littlefield Posts: 6,158	Re: How far can you adjust the generator 3rd brush? Sponsored Links (Register now to hide all advertisements) I have had the charge rate set at 14 amps for the last 20 years, I also have a diode cutout, when I go on a long drive I turn the lights on for a while, have always had long battery life, got 16 years out of the Optima If I was to go on a very long trip I would set it back to 6-10