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Converting to 12 volt system

Can somebody please help me with converting my 1928 D65 to 12 volt. I would like the steps and parts involved if possible. I see in the tech section an alternator.But what about the starter and other componants? I would appreciate any help. My 6volt system is just not reliable and I have to revert to the hand crank too often.
Thanks Lawrence

Re: Converting to 12 volt system


While I’m normally a fan of keeping a system six volts there are good reasons for switching to 12.
I would first take a volt-meter look for where your current is dropping. The lost of a 1/4 volt here and there will make your system undepenable. You may have a poor ground or even bad wiring. I know I've patched several wires on my Durant for that same reason.

But I think the easiest way to convert is to have the old cutout rebuilt as a 12-volt regulator.

I took a spare cutout and removed the inside components, then cleaned and painted everything, it sure looks nice now. Next I sent the empty cutout to:

John F. Regan
Fun Projects, Inc.
PMB #164 2460 W. Main Street - D
St. Charles, IL 60175-1000
(630) 584-1471

and asked him to build a 12-volt negative ground voltage regulator inside it. After I received my new cutout back I simply installed and hooked the wires back as normal. That unit has operated flawlessly since day one, plus you have the added protection of a regulator and not just a cutout.

The last step was to replace the light bulbs. If you have a fuel gauge you should install a drop down resistor, I believe the rest of the instruments are manually operated.

You may want to call and speak to John; I know I did because no modifications to the generator were required. The new unit allowed the old generator to operate at a higher voltage.

The beauty of this conversation is that you can always reinstall the old cutout and lamps and the car is back to a 6-volt system.

Keep in mind that the starter will run hotter, but it should operate for less time, Also if the source of your problem is a bad ground or old wiring, the problem will be there until properly addressed.


Re: Converting to 12 volt system

Thx Rick
I will be checking and replacing bad wireing first.If I have problems agian I will look at the mods you did as they keep things most original.I have pasted your comments to my Durant file for future referance

Re: Converting to 12 volt system


One item that is often overlooked is the starter switch itself...I recall one member chasing down all battery and cable connections, then by chance replaced the switch and BINGO it would crank again as it should.


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