6 volt or 12 volt

[Standing Elk]

Ok, just got my "new to me" 30 coupe home and am starting to sort some things out on it. What are your opinions on doing a 6 to 12 volt conversion. This car had a non working alternator on it and I have some doubts about the health of the battery. I am anticipating having to replace both the battery and the alternator or generator whether I go 6V or 12V. I see Mac's sells a 6 to 12 volt conversion kit that includes a new 12 volt alternator, light bulbs, rectifier, new 12 volt coil, and a starter field coil. Has anyone used one of these kits from Mac'c? It appears to include everything needed to do a complete conversion. Also looks like nothing would be altered to the point of not being able to go back to 6V if you wanted to. Anyway just curious as what opinions I could get. Thanks

[BILL WILLIAMSON]

6 Volt stock system is VERY sufficient! DON'T follow the "FADS"!-- BE your "OWN" Man!
Bill W.

[springerpete]

I have had no problem with 6 v for almost 10 years. If your 6 v system is lacking then you have other issues you need to identify and fix. Stay with what FoMoCo produced.

[steve s]

You will discover that there are strong feelings on every side of every Model A related issue. Decide what your "concept" is for your car and do what it takes. In this case, if maximum authenticity lights your fire, stick with 6 volts--many people are happy with that. If the APPEARANCE of authenticity is good enough for you, then you nave more options, including 6V voltage regulators either built into the cutout can or hidden in the generator, or an alternator built into a generator case. If reliability, convenience for use with modern accessories, and peace of mind is a priority, then join the rest of the world that has switched to 12 V, negative ground: there were good reasons for going to 12V (by contrast, negative ground was apparently just a technical toss-up but done for uniformity's sake.) I've done the switch but not with a kit. The kit you describe sounds complete except for a load resistor to put in series with the horn. I don't know what the rectifier would be needed for.

Eventually, you'll have to confront similar issues, like detergent oil, thermostat, fuses, antifreeze, sealed water pump bearings, shortened Pitman arm, and on and on.

Have fun!

Steve

[Bob C]

You may want to do some research on Macs shipping charges, customer service,
and parts quality. There are plenty of good vendors.

Bob

[Synchro909]

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Originally Posted by bob c

you may want to do some research on macs shipping charges, customer service,
and parts quality. There are plenty of good venders.

Bob

x2!

[BillCNC]

Originally Posted by Bob C

You may want to do some research on Macs shipping charges, customer service,
and parts quality. There are plenty of good vendors.

Bob

Bob is correct, ...

X3

Regards
Bill

[160B]

Standing Elk

I installed a 6 volt positive ground alternator and left the rest original.

I looked at the kit and was surprised by the low cost $137.37

http://www.macsautoparts.com/ford_mo...rsion-kit.html

If you price out the items in the kit the total cost if you bought each item individually is around $335.01, so you save $200.00 by purchasing the kit???????????????

read post #5, #6 and #7

Kit Includes:
1 Alternator (A10000A12) $192.99
1 Starter Field Coil (A11081) $40.99
1 Coil (B6A-12029-B) $30.49
1 Ballast Resistor (A12001) $7.49
1 Horn Resistor / Voltage Reducer (A13802R) $27.49
1 Ammeter (A10850/30) $10.49
2 Headlight Bulbs (B13007E) $4.98
6 Dome, Dash, Cowl & Tail Light Bulbs (V13465D) $5.70
2 Stop Light Bulbs (V13465B) $1.90
1 Electric Wiper Resistor (V12873) $12.49

[marty in Ohio]

My six volt system has served me well for the 24 years that I have owned my '30 town sedan and apparently well for the 87 years that the car has around. But, as all have said, it's your choice.
Also, beware of Mac's.
Marty

[barkleydave]

This topic comes up often with same answers. Do what you like. Why did cars universally go to 12 Volt you ask? Answer: Smaller wire gauge for battery cables. Less amp draw for starter etc. Me personally I tour and have halogen headlights which are as bright as modern cars. I like the idea I can get a battery anywhere. (six volt not always that easy in a pinch) Can jump car with a modern 12 volt car. I can use 12 volt acc. if I whish. You reasons my differ or not matter at all. Fine Point show cars do not qualify for change. LOL

[Jim Brierley]

If you are going to run higher compression, and maybe other mods, go with the 12v system, for easier and quicker starting. Otherwise 6v is OK but do not use a stock generator if headlights or other mods have been made, it will not keep up and will throw solder if you try. I have used 12v since 1959 with no trouble. I also use the stock starter.

[Bob Bidonde]

I have been running 12V systems in both of my Model A's without any changes to their starter motors. If you opt for a 12V system, omit the starter changes.

[Patrick L.]

What are you going to do with the car ?

A conversion 'kit' is not needed. Anything needed is readily available, and, thats not much.
A generator and starter will work fine on 12V. [ To me, an alternator just isn't right]

That said, I find nothing wrong with 6 v. I just use a voltage regulator.

[Charlie Stephens]

You don't need a "new" ammeter, they are junk (at least al of the ones I have seen). Run a jumper wire across the two terminals at the back of the ammeter so some of the current goes through the jumper and some through the ammeter. You may be able to accomplish this at the junction box on the firewall depending on your wiring. You may want to run a wire in parallel to the one from the cutout and hook it to the other side of the ammeter. Use the same gauge wire as the present wire from the cutout to the ammeter. I have done this on my '32 but there is room behind the dash to work with. Remember that the gauge will read low.

Charlie Stephens

[Mike V. Florida]

Originally Posted by Standing Elk

What are your opinions on doing a 6 to 12 volt conversion. Thanks

Leave it alone and use the money you save on gas and drive it.

[jrelliott]

If you have a generator, you can hand crank it or push start when the battery is low. You cannot do this with an alternator. BTW if you want can use a stock generator and run a 12V negative ground system. Just change the bulbs, polarity of the coil, a 12V coil or a ballast resistor, repolarize the generator, swap the wires on the amp meter and a 12V battery. You can probably get a 12V regulator from Fun Projects or Tom Wesenberg that will go in your generator.

[WHN]

Many different opinions will be given. Your the only one that will know what's right.

For 60 years, all of our Model A's have remained 6 volt. Never had a problem or reason to change. Also we haven't added after market electronics. All kept as from the factory. No jewelry. Enjoy.

[Licensed to kill]

[QUOTE=Standing Elk;1533549What are your opinions on doing a 6 to 12 volt conversion. [/QUOTE]
I don't have an opinion but am curious, what do you expect to gain by converting to 12V?.

[BillLee/Chandler, TX]

See http://cedarcreekas.org/TechTopics/1...rn_Signals.pdf

[duke36]

If 12 volt, some say to add the modern bendix on the starter. I had a 6v cutout short somehow and caused engine elec. fire; went to the 1 wire 6 volt alternator after that incident on all 6 volt cars. An Optima battery is a good choice if running 6 volts.

[Ted Duke]

The reason that the manufacturers changed to 12 volts is to save money. By using a higher voltage they could use smaller wires. It is as simple as that. MONEY.

[Fordfan29]

I agree with those saying to decide how you are going to use your car. I converted to 12 volt many years ago on a 29 Tudor we use for long distance touring & have never regretted it. Something to consider if you are in the middle of nowhere & a 6 volt alternator gives out is where are you going to get one. 12 volt alternators are in every parts store & junk yard. Consider your use & needs and build accordingly.

[mike657894]

I switched to 12v for the availability of alternators. I recommend a battery shut off. I had the starter button stick once. I also like to use a fuse block in my car.

[pgerhardt]

Originally Posted by jrelliott

If you have a generator, you can hand crank it or push start when the battery is low. You cannot do this with an alternator. BTW if you want can use a stock generator and run a 12V negative ground system. Just change the bulbs, polarity of the coil, a 12V coil or a ballast resistor, repolarize the generator, swap the wires on the amp meter and a 12V battery. You can probably get a 12V regulator from Fun Projects or Tom Wesenberg that will go in your generator.

This is the first time I have heard this. Are you saying that when the battery is so dead it won't allow the coil to create a spark, a generator will supply enough juice at hand cranking speed, while an alternator won't?

[Dollar Bill]

Originally Posted by pgerhardt

This is the first time I have heard this. Are you saying that when the battery is so dead it won't allow the coil to create a spark, a generator will supply enough juice at hand cranking speed, while an alternator won't?

Have pull started many old cars and tractors with a dead battery.

An alternator needs to see battery voltage in order to produce current.

Also, a real-quick way to smoke test an alternator is to remove the battery cable while the engine is running.

[H. L. Chauvin]

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Nice to maintain everything original with 6 Volts; however, just one (1) humble opinion based on past experiences:

1. As usual, wonderful comments above, and yes, fully agree that "NOW" is the time to consider and think about a 12V conversion, vs. staying with a very functional 6 volt system.

2. Here are a few "Out-of-the-Box" thoughts that so many Model A owners find out "AFTERWARDS", and are later compelled to consider and convert to 12 volts:

A. Not trying to get personal, but are you married; and/or do you have or want a future a girl friend?

B. If so, do you want this lovely lady to accompany you mostly 24/7 when driving your Model A; or are you intending to find a very sweet female in the near or distant future with which to share your Model A?

C. Does your most wonderful female sweetie get hot spells .......... and/or, would she possibly complain a lot if she would presently be compelled to constantly ride with you in the summer in your modern car with your A/C always turned "OFF" ..... all of the time ....... even with all of the windows rolled down?

D. Furthermore, do you live in a sometimes too warm of an area, or do you live in an area where it is "always", (100% of the time), a most bearable wonderful cool area where A/C is NEVER needed?

3. After the Model A FLING gets just a little old, some wonderful females just very politely say "NO" ............. you either get A/C or I will not to ride without A/C.

4. A/C requires 12 Volts.

5. Not an all encompassing Model A scenario; but this is just one (1) slightly different and most friendly Model A 12 Volt "Sexual Consideration".

[Crankster]

Originally Posted by Ted Duke

The reason that the manufacturers changed to 12 volts is to save money. By using a higher voltage they could use smaller wires. It is as simple as that. MONEY.

The 12 volt conversion by the OEM seems to be a few factors, as well as negative ground. Interesting subject for trivia maybe. I've read it was because in part - 1956 or thereabouts, due to higher compression engines becoming widespread. Six volts just didn't have the oomph to reliably turn over the larger engines. Vehicle accessories started to take off in a big way postwar and placed increasing demands on the electrical systems. Wire size played a role too - copper is viewed as a precious metal by the accounting department apparently. Semiconductors and alternators replaced generators, transistors replaced vacuum tubes in radios, making a negative ground system the better choice.

[Kurt in NJ]

Originally Posted by pgerhardt

This is the first time I have heard this. Are you saying that when the battery is so dead it won't allow the coil to create a spark, a generator will supply enough juice at hand cranking speed, while an alternator won't?

With a diode cutout the generator can make close to 4 volts into the system , not have to get over 6 volts to close a reley cutout, I have hand crank started the car with the battery dissconnected, you do have to flip it over pretty quick----

I have been accused of having a12 volt system, my car cranks fast, the lights are bright, from my experience the generator is morereliable than the alternator---the chevy truck that I have had 35 years has had the alternator fail 3 times in 30 years, the model A generator it's been over 40 years without doing anything ezcept a few drops of oil ----

the idea of changing to something you can get at "any parts store" instead of the reliability of proper restoration ----I guess it gives a reason to occupy time and travel from parts store to parts store

[Jim Mason]

http://jmodela.coffeecup.com/mods.html

[Terry, NJ]

At first, when I got my first model A, I wanted to convert to the more powerful 12V. I thought 6Vs were so years ago and I didn't want to replicate some of my early experiences. I asked a cousin, who was flipping Intnl tractors what he thought of converting. He said don't bother! Just install the 6V properly (Cable sizes, clean connections etc) and it will be fine. I met a retired Boeing engineer who was into Ford N series tractors and his advice was keep your connections Clean ,Bright, and Tight! I've found them to be words to live by. Don't just compress the connectors on your cables, solder them! I also am a fan of auxiliary ground cable directly to the starter. The Mod. A was designed to ground through the frame. Almost a century later, the electrical connections and ground paths through the riveted parts is not what as it was designed.
Terry

[Tom Wesenberg]

Like Kurt said, I've also found generators to be more reliable.
Once I restore a Powerhouse, I shouldn't need to touch it again ever.
Maybe check the brush length after 80,000 miles is all.

[ford31]

I bought my alt from Davis,several years ago,coil from local parts supplier,I have for horn adjustable resistor from mouser electronics sits inside frame adjusted for perfect sound,took starter to local alternator starter shop they rebuilt and changed field coils to 12 volt havent touched since did the conversion,you cant go wrong using Davis,I even have his shock kit

[pgerhardt]

Originally Posted by Dollar Bill

Have pull started many old cars and tractors with a dead battery.

An alternator needs to see battery voltage in order to produce current.

Also, a real-quick way to smoke test an alternator is to remove the battery cable while the engine is running.

By "dead battery" do you mean not enough juice to turn over the engine? I am still having trouble with the idea that a generator (not magneto) will produce enough current to excite the coil at hand cranking speed. If so you should be able to start the engine with the battery disconnected? That would be an interesting experiment. However if it worked, you would have to shut right down, as a generator not connected to a battery could burn itself out.

So . . .
An alternator not connected to a battery produces no power, while a generator not connected to a battery produces too much power.

Interesting.

[ChetVL29]

I have a '29 Tudor that I want to swap to HC Head, touring cam. I appreciate the pros/cons of each, but think I'll upgrade to 12V. Thanks for the info guys

[MAG]

There is no need to change to 12 volts unless accessory installation demands it such as AC. If the conversion is made, in spite of comments made about converting the starter not necessary, it just is not true. I have had 5 come into my shop that the starter ring has been pushed off because of 6volt starter on a 12volt battery. Happened on my own car. Failing to convert the starter is like having a pet rattlesnake.....one day.

[Conaway2]

I’ve had the original 6V positive ground system on all my Model A’s since I bought my first one in 1967, and have had no issues other than periodic battery replacement.

The main reason many switched to 12V is no longer valid, as LED headlights can now be easily run on the original electrical system, and USB charging ports will also work on a 6V system.

Good luck with your car, whatever you decide to do.
Jim

[Badpuppy]

Originally Posted by Conaway2

The main reason many switched to 12V is no longer valid, as LED headlights can now be easily run on the original electrical system, and USB charging ports will also work on a 6V system.

Very true. The only reason now to convert to 12V negative ground is for compatibility with add-ons, such as a/c or modern electronics.