Curious question on alternators

37 Coupe

37 Coupe

Well-known member
I do not have a Model A now but years ago when I did never gave much thought to the generator just ran the car a 30 roadster. I am always looking at Model A's for sale and especially the Model A I have always loved the 31 Deluxe Phaeton,one is on Ebay now in Ohio but out of my price range. It has what leads to my question ,an alternator, why does it seem most Model A ,even ones that are supposedly MARC winners equipped with alternators. Were the generators worse than say the 3 brush on my 37 Ford? Are these (alternators) removed at judging? Or acceptable because of touring dependablity? Seems it would be more easier to swapout then on a flathead Ford as mine with fan pulley attached.Just a curious question,I can see that a 6volt alternator would alleviate charging concerns but surprised to see so many original restorations with this one exception.:confused:
 
I can tell you why I use an alternator. I can get a rebuilt one for $55 locally, less than the cost of an electronic voltage regulator for a generator.
 
37 Coupe said:
I do not have a Model A now but years ago when I did never gave much thought to the generator just ran the car a 30 roadster. I am always looking at Model A's for sale and especially the Model A I have always loved the 31 Deluxe Phaeton,one is on Ebay now in Ohio but out of my price range. It has what leads to my question ,an alternator, why does it seem most Model A ,even ones that are supposedly MARC winners equipped with alternators. Were the generators worse than say the 3 brush on my 37 Ford? Are these (alternators) removed at judging? Or acceptable because of touring dependablity? Seems it would be more easier to swapout then on a flathead Ford as mine with fan pulley attached.Just a curious question,I can see that a 6volt alternator would alleviate charging concerns but surprised to see so many original restorations with this one exception.:confused:
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OK let's take a look at your points,

...why does it seem most Model A ,even ones that are supposedly MARC winners equipped with alternators?

You can't be a MARC or MAFCA winner with an alt.

Are these (alternators) removed at judging?

Yes

Were the generators worse than say the 3 brush on my 37 Ford?

No

It is easier for some to just pop in an Alt then it is to find a place to repair the gen. There is also the matter of accessories. Some owners that tour with there cars also have accessories such as CB radios, radios, High power lights etc. Thus the need for more power.
 
The alt gives the illusion of reliability and may be lower cost then buying a rebuilt generator.

Then there is the added euphoria of more amps to charge. This is a false hope as most alternators are not installed with the belts tight enough to be of any use.

Most do not realize that the single wire alt are a constant drain on the battery when powered off so you have to install a batt switch if you do not drive much.

We also have the argument that the alt is needed to run halogen bulbs. That is very false. With the properly restored car and the direct replacement bulbs from Australia you can run 60 mph down back roads with confidence.

We have to throw in a bit of profit margin. My guess is the switch to an alt is a big money maker for the stores. Especially since guys are frequently going to 12V so they can also sell the parts to do the switch. I know the Nurex guys have a great story on how unreliable the original gen was, if you listen to them you would wonder how the car came off the line with the ability to charge a battery.

My brother was looking through some documentation on the A generator. You should expect to get between 18 and 22 amps out of the original A generator.

So what is better.

What ever you are happy with. My brother only has 40 trouble free years on his generator so I plan on using a properly rebuilt gen.
 
I think I know the answer to this at least on a Ford.It would have been the 39 Ford Deluxe mayby standard also but I do know the two models used different generators,standard still using fan pulley mount. The voltage regulator was a small firewall mount I was always told it was basically a remote cutout and it was replaced either during the 1939 Ford Model year or in 1940,I believe all 1940 models had the larger black voltage regulator that was virtually unchanged all through the 6 volt era. I remember reading one time or mayby the old Ford garage mechanic I knew told me that the 39 voltage regulator/remote cutout was one of Fords first free replacements as the term recall was not used then,lots of people never bothered until car was back for service if at all. This was always a pet peeve with me when I was doing a 39 Ford,that Early Ford V8 Club required the original small cadium plated box that was factory installed and deemed by Ford to be replaced a year later,don't know if they were unreliable,unsafe or just obsolete,but Ford said they must go in 1940 and V8 Club says they must stay to this day.
 
I think of alternators as being less reliable than a restored generator. I restored my powerhouse about 9 years ago and installed my electronic voltage regulator in place of the adjustable brush. I don't expect to have to remove the back cover as long as I live, and hopefully that'll be a lot of years. I have all the power I need for bright lights using original bulbs and good original silvered reflectors. I run my fan belt loose enough that I can push and pull it 1 1/2" half way between the fan and generator. My generating system is one thing I never give a thought to because it is so reliable with it's original cutout and generator.
 
I like the Model A because it does have a generator. There is nothing wrong with a generator that is in good condition. I also enjoy driving a vehicle that uses absolutely no electronics. I think some of these updates are about what is familiar. A lot of people don't know anything about generators, or points, or mechanical (drum) brakes, and assume that these things can't be any good. Not quite that simple.
 
Bill Steiner said:
If the Alt is set up correctly the one wire Alt will not run the batt . down. Bill
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Bill..Amen to that! Also, can not beat 'piece of mind' that comes with reliability/the long run/touring. However, I do carry a rebuilt generator for 'backup':cool:

Hmm, it would be interesting to take a count of how many Model A owners(including those that change back to alt..after the show:)) to learn the percentage of owners who use alt over gen because of reliability!
 
My first Model A had an alternator on it when I bought it. It worked OK. All of my other Model A's over the years had Generators. They also worked just fine. If it is not broke, I see no reason to "fix" it. Generators worked OK in Henry's day and they still work just fine in my opinion today.
 
I went to 12V alternators on both my A's as I wanted to run a stereo and use my Ipod plus my CB when I go on tours and charge my phone
 
Fred said:
So you don`t have a Model "A", You have a Modified Model "a" !!..
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Most, if not all, of of the Model A's that were being driven in the 30's had SOMETHING on them that was not as Henry built it. Accessories and add-ons were a big thing "back in the day"
 
How is using an alternator making the "A" more reliable??

Is it because you can go from NAPA to NAPA replacing it?

Is it the reduced belt life ?

Is it because it is modern,electronic?

Is it because rebuilding a generator properly a lost art?

It will be hard to convince me that the generator that was rebuilt by a 16 year old 40 years ago, abused with a 18A+ charging rate for 50cp bulbs and still working untouched with the same waterpump and belt is less reliable as a system than an alternator.
 
Mike V. Florida said:
All diodes have leakage and the leakage will slowly draw down the battery.
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All batteries have internal resistance that is insufficient to keep a battery from slowly running down. :eek:

Now for the ongoing G & A comparison

Gen = total output amps across brushes on segmented commutator. :mad:

Alt = field amps across brushes on smooth slip rings. :)

"Alternators have several advantages over direct-current generators. They are simpler, lighter, less costly and more rugged. They use Slip rings providing greatly extended brush life over a commutator"

"Automotive alternators have a voltage regulator built into them which operates by modulating the small field current in order to produce a constant voltage at the stator output. The field current is much smaller than the output current of the alternator; for example, a 70 A alternator may need only 2 A of field current. The field current is supplied to the rotor windings by slip rings and brushes. The low current and relatively smooth slip rings ensure greater reliability and longer life than that obtained by a DC generator with its commutator and higher current being passed through its brushes."

I am running an alternator but will be happy to attest to the longevity of the Model A generator on my garage floor. It's lasting longer as each day goes by. :D
 
CarlG said:
Most, if not all, of of the Model A's that were being driven in the 30's had SOMETHING on them that was not as Henry built it. Accessories and add-ons were a big thing "back in the day"
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You mean like this? Among the many reasons I wish Dad were still around is that I wish I could ask him about all the stuff on his car--wondere how he powered all those lights and the radio.

scan0028.jpg


Steve
 
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