31 ford

I am trying to wire my dads 31, went to 12v, but i'm kinda lost could use any help. thanks. Anyone have a diagram?


Assuming it has just been converted to 12 volts the drawing is the same. The generator may be an alternator but makes little difference the wiring is the same.

wiring-diagramcolor2sm.jpg
 
Just be aware that 12 volt systems are typically negative ground and Model As are originally positive ground.
 
Just be aware that 12 volt systems are typically negative ground and Model As are originally positive ground.

This opens yet a larger can of worms. Now, not only do you need to add a ballast resistor to the coil, you have to reverse the coil wiring for the negative ground system, or the spark polarity will be backwards and the engine will run poorly. And you will be scratching your head, wondering why... :confused: blaming it on the carburetor, ethanol in the gas, something else... ;)

And what is the plan for the 6 volt horn? :confused:

Oftentimes this switch to 12 volts is done just so you can put a 12 volt negative ground alternator on a car. That is the tail wagging the dog!!! :eek:

And the 12 volt alternator is often added as a band-aid (*sticking plaster to many of my friends -- you know who you are! :cool: ) because the 6 volt headlights were not restored properly, they won't focus, they don't light up the road. :( So you think you need 12 volts, perhaps halogen bulbs. Where does it end? :confused:

People who know me know that I am not a purist. One of Model A's has air conditioning, for god's sake! :p But I resist the uninformed, knee-jerk reaction to convert to 12 volts, when the real, underlying problems can be easily addressed. :o

</end rant>

My apologies in advance if I have offended anyone here. Please smile! :D
 
Minerva had a 6 Volt alternator & sounded like 12 Volts when it started, because the BATTERY WAS ALWAYS FULLY CHARGED!
Horn worked excellent & lights were bright!
Bill Sixvolt
 
My car was converted to 12v before I bought it but this thread got me to thinking. Where do you readily find 6v batteries that fit the Model A battery box these days? Say you were on a tour?

As I said my car is 12v and I'm not suggesting anyone switch. But I can walk into any place that sells car batteries (Even Costco) and buy a Group 35 12v Battery.
 
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Any farm store has 6 volt batteries, as well as most auto parts stores or Batteries Plus.

I'd be installing a new battery before I left home with a questionable battery. Also, don't forget you can always hand crank the engine as long as the battery isn't totally dead.
 
Any farm store has 6 volt batteries, as well as most auto parts stores or Batteries Plus.

I'd be installing a new battery before I left home with a questionable battery. Also, don't forget you can always hand crank the engine as long as the battery isn't totally dead.

Yes, hand crank is there for a reason. Batteries of the Model A era were often too discharged to crank the engine. Push start is even easier than hand crank.

My starter decided not to turn over one morning when I was heading out to a 4th of July Parade. My daughter pushed me down the driveway at the house and the car was running before I got to the end of the drive. This was a cold engine. I popped the clutch and it was running. Kept it running all during the parade. Got a short push start when it was time to go home.

I have been touring with Model A's for a long time (decades) and do not recall one time when a car's battery failed and someone had to go buy a battery in the middle of a tour. I'm sure it happens, but not very often.
 
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Thanks Tom and Jim. I can't think of many 'Farm Stores' in Southern California, haha. Maybe further north and inland. :p:p

I have never really looked for a 6v Battery, I was just curious if it would be hard to find one. Similar to finding 6v light bulbs?
 
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Thanks Tom and Jim. I can't think of many 'Farm Stores' in Southern California, haha. Maybe further north and inland. :p:p

I have never really looked for a 6v Battery, I was just curious if it would be hard to find one. Similar to finding 6v light bulbs?

It probably won't be long before many of the ignition parts we grew up with will be special order or hard to get. Rotors, caps, points, and condensers have gone away for several years already. When I worked at the junk yard I tried to tell the boss he should be saving a lot of the round headlamps, (especially the bullseye and T3) and many other such parts, but he didn't care.:mad:
 
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