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nkaminar · 09-16-2023, 05:53 PM

The Model A generator is crude compared to modern alternators. The Ford dealer in 1930 would measure the battery's electrolyte specific gravity when the cars came in for service and adjust the generator output accordingly.

8 Volts is a little high for a 6 volt battery and may cause your Optima battery to outgas. You could try burning the lights to limit the voltage but you may have to turn up the generator output. Back in the day, people would add a voltage regulator to the generator to make it voltage regulated like a more modern car. People now will install an alternator if they do a lot of cruising. A modern alternator is voltage regulated.

The way the Model A generator works, without getting into the technical details, is to limit the current as the rpm increases, but it is not exact so the current, and thus the voltage, is generally proportional to the rpm.

It sounds like you may have an electronic cutout, that has a diode inside. The diode will turn on and conduct current when the voltage difference is about half a volt. So there is always about half a volt drop across a diode when it is conducting.

09-16-2023, 05:53 PM	#2
nkaminar Senior Member Join Date: Jan 2012 Location: Western North Carolina Posts: 4,002	Re: What is normal charging behavior? The Model A generator is crude compared to modern alternators. The Ford dealer in 1930 would measure the battery's electrolyte specific gravity when the cars came in for service and adjust the generator output accordingly. 8 Volts is a little high for a 6 volt battery and may cause your Optima battery to outgas. You could try burning the lights to limit the voltage but you may have to turn up the generator output. Back in the day, people would add a voltage regulator to the generator to make it voltage regulated like a more modern car. People now will install an alternator if they do a lot of cruising. A modern alternator is voltage regulated. The way the Model A generator works, without getting into the technical details, is to limit the current as the rpm increases, but it is not exact so the current, and thus the voltage, is generally proportional to the rpm. It sounds like you may have an electronic cutout, that has a diode inside. The diode will turn on and conduct current when the voltage difference is about half a volt. So there is always about half a volt drop across a diode when it is conducting. __________________ A is for apple, green as the sky. Step on the gas, for tomorrow I die. Forget the brakes, they really don't work. The clutch always sticks, and starts with a jerk. My car grows red hair, and flies through the air. Driving's a blast, a blast from the past. Last edited by nkaminar; 09-16-2023 at 06:00 PM.