Orig 6 volt generator with 12 v reg. & bat.

40larry

Senior Member
IS THERE ANY REASON WHY AN ORIGINAL 1939 TO 1948 FORD GENERATOR CAN NOT BE USED WITH A 12 VOLT REGULATOR AND 12 VOLT BATTERY ?


40larry
 
without going into the details, i'll say that as the question is worded, the answer "NO" there is no reason why you can't. but "yes" there are plenty of reasons why you shouldn't and is unlikely to work well or for long, if at all.

the details are contained in many forums on the subject of the 6v to 12v conversion process on Fords and many pre-1950's cars from all over the world. they can be found by googling. they can also be found using the search tool on this site. good luck. :)
 
Steve Blancard in VA can convert generators to 12V. It’s kinda labor intensive though, the field coils are not available as I recall so he has to make em by hand.
 
The armatures can take it but the field windings have larger gauge magnet wire and fewer turns. The standard 2-brush 6-volt types were generally only 30 to 35 amps capable. I'm not sure what a 12-volt conversion would be capable of. A person should use field coils that match the regulator that is needed if possible. The regulator controls it so a 1956 or later generator set up could be used to emulate the design characteristics for an older type.
 
AFAIK, a 6v generator may generate from time to time sufficient voltage (13.5 to 14.8v) to be passed on to the battery by a 12v regulator to charge a 12v battery, but not often enough to keep it charged properly. and so, the battery would slowly discharge.

...interesting question. why not give it a try and let us know how it goes? i'd be interested in hearing about it. i always find empirical evidence compelling. :)
 
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I have have 12v converted generators in stock or can convert yours. Glad to help if interested.
 

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IS THERE ANY REASON WHY AN ORIGINAL 1939 TO 1948 FORD GENERATOR CAN NOT BE USED WITH A 12 VOLT REGULATOR AND 12 VOLT BATTERY ?


40larry
Yes there is a very good reason why a six volt generator will not work WELL in a 12 volt system. The difference between a six volt generator and a 12 volt generator is the gauge (size) of the wire used in the field coils and armature windings,, which is much larger in the six volt generator. It requires much higher RPM before the generator will produce the required 13 volts to close the cut out contacts to commence charging the 12.6 volt battery. Likewise for a given RPM compared to a 12 volt generator the 6 volt generator will require a much higher RPM to say charge 15 amps. Another problem is the 6 volt field coils on 12 volts will draw twice the current (amps) of the 12 volt field coils. This heavier field current is carried and controlled by the voltage and current regulator contacts which will enjoy a much shortened life. YES, YES, I know some of you have used a six volter for over 59 years with no problems. But the design facts are that a six volter will NOT WORK AS WELL on 12 volts as it would on six volts. As they say Horses for Courses.
Regards, Kevin.
 
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