Using the original generator in a 12v car?

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Using the original generator in a 12v car?

Post by Jedediah » Thu Dec 05, 2019 9:15 pm

My '23 Model T was converted by the previous owner to 12 volts, with a single coil and distributor. It still has the stock Generator and cutout, which he says he never got the chance to regulate so as to charge sufficiently for 12 volts. I see that Langs and several others carry a replacement cutout specially designed for a 12 volt conversion ( ), but it is backordered both in Langs and every other catalogue I can find. Is this voltage regulator necessary to using the original 12 volt system, or can the original cutout be used? If so, how would one best adjust the original generator to charge the 12v battery correctly?
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Re: Using the original generator in a 12v car?

Post by Scott_Conger » Thu Dec 05, 2019 9:54 pm

if the cut-out voltage matches the battery voltage, the generator will provide the necessary voltage. It is the current you regulate within the generator

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Les Schubert
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Re: Using the original generator in a 12v car?

Post by Les Schubert » Thu Dec 05, 2019 11:17 pm

Lots of people have done this.
1. Replace the cutout internals with a diode
2 set the current output to about 1/2 of what you would consider for a 6 volt system. So probably a maximum of 5 amps. When I have done this I disconnected the field ground connection inside the generator and brought it out and ran it to a heavy rheostat located on the dash. A continuous heater blower control works alright. Connecting the other side of the rheostat to ground and you can adjust the amps as you drive

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Re: Using the original generator in a 12v car?

Post by lesvonnordheim » Wed Dec 11, 2019 12:44 am

Suggest looking at the Fun Projects regulator.

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