12 volt conversion

dsarge390

dsarge390

Member
Hello, everyone.

I'm doing the 12 volt conversion over the winter season. Anyone have a preferred vendor to purchase a complete kit from? I'm not interested in fabricating brackets, or piecing several pieces together to save a buck. Thank you in advance.
P.S., no need to convince me to stay with the 6volt system....
 
what do you need to make brakets for? buy the alternator kit from one of the venders that sells them, the one wire GM style ones, and bolt it on change out your light bulbs, and coil
 
Yes, Beater. Most kits do come with the brackets. Some people make brackets out of spring shackles themselves to save $$. Then buy their own alternator, etc. I'm just not interested in that. That's all I was saying.
 
well when I did mine I bought the kit from snyders I think. GM delco alternator. brakets all there new pulley ect ect. I changed nothing in the wireing, simply hooked up the wire that used to go to the gen to the alternator. been workin fine


rdit I bought the newrex kit all good so far
 
Don't forget to convert the starter too. I know you will hear ...."I've been running mine for x number of years"...... But that engaging force of 12 volts on 6 volt coils can and will push the starter ring gear off the flywheel.
 
Charlie Stephens said:
Remember you can use the original amp meter by running a shunt to carry some of the current.

Charlie Stephens
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???


I don't understand.


An ampere of current is an ampere of current irregardless of the voltage. The stock amp meter works just fine with a 12v conversion. True, the 20 amp swing is low and switching to a 30 amp meter is often done, but "a shunt to carry some of the current"???? No.
 
dsarge390 said:
Has anyone used the kit from Vintage Auto Garage? It looks a little more "original" With cloth wiring and a faux generator, etc...

https://www.vintageautogarage.com/1928-1931-Ford-Model-A-12V-90-Amp-Powermaster-kit-p/fp2831.htm
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I haven't used a kit but the one in your link appears to use the Powermaster PowerGEN, which I do have and is a nice unit. It looks a lot better than the GM one wire also. The GM just doesn't "look right" on a Model A.
If you don't want to chase down the rest of the parts for the 12v conversion individually, then IMO the kit should fill your needs.

30942048998_a8a0733943_z.jpg
 
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If you go with an alternator. They have a smaller pulley so they spin faster at lower speeds, you will also need a clog type belt to fit the smaller diameter pulley. The stock belt is too stiff.
 
Patrick L. said:
One thing that hasn't been mentioned is that the generator will work fine on 12v.
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Correct, and you can add an electronic regulator to it so you don't need to worry about over-charging. You can even re-polarize the generator for negative ground. (Caveat - an alternator can supply much more power if you really need it)
 
Patrick L. said:
One thing that hasn't been mentioned is that the generator will work fine on 12v.
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True. Doubles its power - same current, twice the voltage. Don't know if there's a regulator available for it though. Original cutout might have problems.

Besides battery, coil, bulbs and starter, don't forget the horn and electric wiper motor (if present) will need conversion as well. (I see the above kit includes 2 heating elements to put in series with those. Not efficient, but avoids rewinding.)
 
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Badpuppy said:
Original cutout might have problems.
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The original cutout works on 6V only. You will need a solid-state cutout (diode type) or a full regulator (like the one from Fun Projects)

I have a 6V Sparton horn that is wired in series with a 1/2 ohm power resistor.
 
If you call up a reputable Model "A" parts supplier, they should be able to build you a conversion kit. I recommend Bratton's. Be sure to call the dealer because you will have some decisions to make:
> Type of 12V headlights;
> Type of turn signals;
> Type of tail lights;
> Dome light?
> 12V horn?
> 12V to 6V voltage reducers for any 6V accessories you have.


You do not need to do anything with the starter motor. Change the Bendix starter drive to a modern one. The Group 25 battery you will need to buy locally.
 
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Why buy the whole kit. As Patrick L said you can use your old generator and a 12V battery. The battery is what determines the voltage our of the generator. If the generator becomes unloaded from the battery will produce up to 40 Volts. You can even change the polarity at the same time by re flashing the generator. You will need the bulbs and a different coil or use a dropping resistor for the coil. Send me our email address and will give you a chart with all the electrical and bulb numbers. jrelliott42@gmail.com
 
Good Model 'A' Morning...Just an observation...Some folks with six volt, ad a second 00 ground strap over to the transmission case and find quite an improvement in cranking speed. Might be worth trying before going to the expense of 12 volt. Ernie in Arizona
 
Patrick L and Sparky are correct . I run my original generator on 12 volts with good results . Though the original type cutout can work , I use the Fun Projects can style voltage regulator that looks the same and takes the place of the cut out . No wires will need to be changed if you continue to run positive ground . If a person wants to change to negative ground , they will need to reverse the wires at the coil and the ammeter . The battery cables will also need to be switched to negative ground if you choose to run negative ground . An original or replacement six volt coil can be used on 12 volts If a resister is used at the coil connections . I prefer the cleaner look of a 3 OHM coil without the need of a resistor. I have used the Pertronix flamethrower coil for hotter spark , quicker starts and more power for better performance . The original starter has worked good for me as well as others . The bulbs will need to be changed and a resister will need to be used on the horn and electric windshield wiper if
used .

There are at least two voltage regulators that can be bused with the original generator on 12 volts. The Fun Projects can style voltage regulator has worked great for me . The Peterson 12 volt voltage regulator that connects at the generator band also works on the model A generator . The voltage regulator that takes the place of the adjustable third brush only can be used on six volts . If a person wants to use the most powerfull halogen head lamps and other high draw accessories they will need to use a 60 amp alternator . Being as all of the 12 volt alternators that are offered in the model A catalogs are negative ground , it will be necessary to change to negative ground if the 12 volt negative ground alternator is used ..
 
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