12 Volt Conversion

[A-Man]

I am planning to convert my 6 volt system over to a 12 volt system. Are all the alternators from Model A vendors the same? Are there comparable alternators available from NAPA or other auto stores? If so, what one best fits? Would it be best to purchase one from a Model A Vendor along with the bracket?
Any pointers would be appreciated.
Thanks.

[1931 flamingo]

Covered many times here and within the last few days. Do a search. Easiest way would be from an A vendor. Others will chime in I'm sure.
Paul in CT

[sturgis 39]

I will be the first one to ask WHY? I run six volt with a generator and have no problem. Like I always say " If I wanted to drive a Mustang too I would buy a Mustang too".

[jrelliott]

I have a bulb chart that will give you all the bulbs required for the conversion with their candle power so can put in brighter bulbs if you want. Send me your email address and will be glad to send it to you. Also have a chart with all the other electrical parts on a Model A ie brushes for starter, points etc. If you are using a 6V horn will need to a Ohmite RKS2RO resistor for the horn. Have not found a suitable one for the electric wiper. You can go to a NAPA or Auto Zone store and purchase a 35 to 60A rebuilt GM10SI or GM12SI and change to single wire or can use the altenator as is with a small modification that I can tell you about that will get the altenator charging immediately. You can make the bracket for the altenator to motor from a spring shackle easily with just a few holes modified. Then you will only need the smaller pulley for the altenator from a vendor as the pulley on the GM altenator is not wide enough

[Jason in TX]

Get the bracket. Makes life much easier.

[Purdy Swoft]

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Originally Posted by A-Man

I am planning to convert my 6 volt system over to a 12 volt system. Are all the alternators from Model A vendors the same? Are there comparable alternators available from NAPA or other auto stores? If so, what one best fits? Would it be best to purchase one from a Model A Vendor along with the bracket?
Any pointers would be appreciated.
Thanks.

I am running my roadster on 12 volts with the original generator and it works great!!!

First if you think that using one of the alternators from any of the vendors will make it easy to find a replacement on the road or at the local parts house, think again! This was mentioned here a few days ago, the one wire hook up alternators, six or twelve volt have been converted and are not sold at your local Pep Boys or NAPA. Most if not all one wire converted alternators require the engine to be reved pretty high before they will begin to charge, not only this, some will never show much more than a 2 or 3 amp charge and don't always keep the battery charged, if you don't drive them pretty regular. It has also been mentioned that the converted alternators have a slight current draw and if not driven on a very regular basis the battery won't have enough power to turn the starter and fire the distributor. I have alternators on a couple of my cars and I prefer the generator any day. The only advantage of the alternator would be if you needed to run lots of accessories and the more powerful quartz halogen bulbs.

I don't run any accessories on our roadster and I use the less powerful halogen bulbs from Australia. these bulbs are easy to obtain and are much better than the original type 50 candle power bulbs. I wanted brighter headlamps and faster cranking so that my wife, daughter, and grandaughter would have no problems cranking and driving our roadster. Bulbs, batteries and battery cables are readly available for the 12 volt system and much less expensive.

Changing over to 12 volts with the original generator is VERT VERY easy!!! Other than the common sense things like bulbs, you will need the 12 volt battery, a resistor for the original coil or use a 3.0 ohm coil and a Fun Projects voltage regulator. This regulator takes the place of the cut out and looks like the replacement cut out that has been sold for years by the model A vendors. This regulator can be had in 6, 8, and 12 volt in positive or negative ground. I have used this regulator 12 volt positive ground on our roadster for five years with no problems.

The original wiring harnesses will work great with this setup. Original type six volt wires are larger gauge than modern 12 volt wiring and will carry the extra voltage with no problems. If you leave it original positive ground no wire connections will need to be changed. if you need to run the negative ground regulator you will need to reverse the connections at the ammeter and battery. you will also need to re polarize the generator if you wish to run negative ground. To repolarize is simple, you will just need to use a wire to jump across the posts of the cutout for a couple of seconds, BEFORE installing the regulator.

Here is a couple of things that i did for extended reliability and these are optional. I used the modern starter drive and the generator cooler band, both from Snyders. For electronic ignition type performance ( I think better) I used the Pertronix flame thrower 40.000 volt epoxy filled 3.0 ohm coil. this coil looks just like any other replacement coil and gives instant starts no matter how bad the girls mess up when trying to get the A CRANKED. This coil gives a good boost in power and the spark plugs run clean.

This set up has been very dependable and we have had no problems in 5 years. If you run an alternator you will experience some of the quirks that I have mentioned and you will get a lot of negative comments about the alternator not being original. The generator is pretty simple and if they can't see the battery there will be no other visible changes to the car. All wiring will remain unchanged. Good luck, whatever your choice.

[jrelliott]

BTW is if anyone is intrested in the bulb chart and electrical parts chart(which has a lot of info about the altenator modifications send me an email. My email is [email protected] and I will send it to you.

[TinCup]

I for one have never understood the rush to convert to 12V. With the quality 6v altenators out there and the halogen 6v headlight bulbs I just don't see the need. The coupe has been 6v for 80 years now and the last 6 I have owned it. It have never even considered it.

What is the advantage of this conversion??

[Mike V. Florida]

Originally Posted by TinCup

What is the advantage of this conversion??

If it's newer it must be better!

[Pepsi Mechanic]

I agree with the 6 volt system . Good battery ... good conections ... great running . I have never had an issue with our Pepsi truck --- plus it doesn't cost anything

[BRENT in 10-uh-C]

Originally Posted by Mike V. Florida

If it's newer it must be better!

Seems logical to me???

.

[Jason in TX]

Originally Posted by TinCup

What is the advantage of this conversion??

One advantage is the ability to have a happy wife sitting it 65 degrees of comfort on a 104 degree Texas summer day!!

[Tom Wesenberg]

Originally Posted by Jason in TX

One advantage is the ability to have a happy wife sitting it 65 degrees of comfort on a 104 degree Texas summer day!!

Adding A/C is the only reason I can see to go to 12 volts. Now, I need to get busy and make a 6 volt compressor clutch!

[TinCup]

Ok Jason I just had to see the light. You know it's so much cooler here in OKC we don't even think about air-conditioning.

I am working with John Lyle to see if we can put together a meetup in Ardmore or the Lake Murray area. I don't know you if you know John but he is a DMAFC member as well as my cousin.

www.soonermodela.org

[Jason in TX]

Haha. Yeah. OKC is almost the North Pole compared to Dallas! hehehe We both know about how fun summer can be!!

Lake Murray State Park would be a great trip! I am familiar with the Lyles. I hope that something gets put together!

[jerry shook]

I Have 3 (A) all 6 volt with alternator and optium battery. never had a problem crank easy halogen lights are brighter then my newer car . BUT if you are looking to put in radio , charger , 2 way radio you might need 12 volt .

[CarlG]

Originally Posted by Tom Wesenberg

Adding A/C is the only reason I can see to go to 12 volts. Now, I need to get busy and make a 6 volt compressor clutch!

Where were you when I needed you -- when I put A/C in my 54 Ford, way back in the early 60s??? Changing that vehicle to 12v was a royal pain!

[brianthelion02]

Lmao!!!!!!!

Originally Posted by tom wesenberg

adding a/c is the only reason i can see to go to 12 volts. Now, i need to get busy and make a 6 volt compressor clutch! :d

[Purdy Swoft]

Originally Posted by TinCup

I for one have never understood the rush to convert to 12V. With the quality 6v altenators out there and the halogen 6v headlight bulbs I just don't see the need. The coupe has been 6v for 80 years now and the last 6 I have owned it. It have never even considered it.

What is the advantage of this conversion??

There is NO rush to change. The available alternators have several quirks that I mentioned in my previous post above The six volt halogen bulbs cost more than the 12 volt halogen bulbs, and are not locally available . The six volt bulbs and alternators are only available from the model A vendors. The six volt bulbs don't last as long. Have you priced a 6 volt battery lately??? About the only thing that still uses 6 volt is golf carts and some old tractors. Six volt batteries and componets are getting harder to find.

Right now I have five model A's running and have owned driven and repaired model A's for over 50 years, most of these have been 6 volt. I wouldn't convert any model A to 12 volt that wasn't giving problems and still had a good battery.

Besides the 5 running model A's that I have I've got 8 more. Whenever I build up another model A, I prefer 12 volt and usually go this route for the reasons that I mentioned here and in my previous post.

Anybody can do as they please or feel is really a better idea. That is whatI usually do.

[sturgis 39]

I do not need or want all of the stuff mentioned. I do not want to listen to a radio, two way radio or air conditioning. I think the fun of driving a model "A" is leaving that stuff at home including the wife. I believe in the KISS principle. I enjoy my own thoughts more than some radio announcers verbage.

The wife always rides along and never complains.