THINKING ABOUT 6v. ALTERNATOR INSTALL

[A-Jay]

If I were to install a 60 amp 6v pos. Grd ALT. are there any other things I would need to do to make it right or better. Also do I want to stay pos. Grd. I would like to have better lights,signals, horn when running, Thanks for your replys.

[RonC]

no need to reverse ground. An alternator is not needed unless you are going to do a lot of night driving or load up your A with modern electrical assessories. You can have problems with the fan belt being to tight and ruining your water pump bearing. You also are more prone to fan belt squealing. A good stock electrical system works very well unless you overload it with electrical stuff. Most important with a stock system is good grounds! Much written on that subject.

[Barry B./ Ma.]

I have a 30 or 35 amp alternator on my coupe with directionals and find that quite adequate. No need for a 60 amp unless you have a lot of power demand such as AC etc. Mine has been a simple, trouble free unit.

[Kevin in NJ]

The alt is being pushed as the fix all for a part that has done fine for the last 80 years. You need to first look at your electrical systems. Why spend $100 or more when you do not know if it will fix your problems???

Do you know how to troubleshoot with a voltmeter? If you do not then ask someone who does help you.

First start with cleaning all your connections and inspecting the connectors for frayed wires, poor crimps, and good solder.

Go through and make sure the ground paths are actual paths. In our attempts to restore we do a great job of painting everything. The ground path in the A is battery to frame then through a bunch of paths to other places. The headlights go through the fender brackets, the headlamp bar and through the ball and socket. The engine goes through the springs, shackles, axles and or the engine pans.

Make sure your generator is properly set up. Where is your third brush? Do you understand what the third brush does?

Good reflectors and good connections will also improve your light. If you drive a lot at night I would switch over to the halogen bulbs that are direct replacements for the original bulbs. They will give you bright light with your generator. They use all the original sockets. Incidentally, do you have original or repro sockets and reflectors in your lamps? The originals work much better and the repro reflector is just not focused properly to work.

The horn needs to be properly rebuilt. The horn could need a good taking apart and proper cleaning and lube. What about the horn contact too? Dirt on the switch contacts could reduce the amount of current to make the horn work. Have you played with the horn screw adjustment? You might have to change the settings between parade and driving as you do not have as much current in a parade.

The switch to the gen is not without it problems. You have to remember the days when you had a V belt pulley on the alt. If it was the least bit loose you did not get a full rate. Usually the belt would squeal as it slipped if the belt was not so tight the pulley would not move when you pushed it with a finger. I think you will be lucky to find an alt on an A that is not so loose it could be spun with one finger. I have seem them loose enough the alt will spin a couple of revolutions with a flip of your finger. The alt may be able to put out 60 amps, but only if they belt is so tight it can not slip. In reality you are only getting some fraction of that top amperage because you should not tighten the belt tight enough. So if you are going to properly install the alt you best also make sure your water pump is up to the job too.

Then there is the other reality. Does the A need more than the 20 amps the generator will output? The answer is NO. Even with the halogen headlight bulbs from Australia you are fine with the regular generator. You would have to put on some major current hog accessories to require an alternator and even then the alt may not be able to really output enough current cause the belt is never tight enough.

Then there is the whole reliability myth. There is a lot of people having problems with their alternators. There does not seem to be a month going by where someone is having some kind of troubles.

Hope this gives you a better perspective.

[gilitos]

I'm with Kevin. A well set up generator with good clean connections to all of the electrical accessories (and the battery!) works superbly. I've been using a totally stock electrical system in my 30 Tudor since 1975; never had a problem on the road (including cross country trips), never overcharged/undercharged a battery, and my batteries typically last about 5 years. If I'm planning a long drive at night (e.g. more than an hour) I might bump up the charge rate with the third brush, but I'm not even sure that I need to do that. Every time I've considered something like a regulator, for example, I keep returning to the "if it ain't broke, don't fix it" mantra. The bone stock Model A is one heckuva piece of engineering.

[V4F]

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i changed to an alternator mostly because no maintanance . had trouble with generators lasting on long runs . had one catch fire . generators are just fine , alternators are just evolution ............. steve
6v pos grd 60 amp

[elklake]

Kevin in NJ:
Excellent feedback!
Your detailed response is what makes this site so valuable to those of us that are new to the hobby and have a lot to learn.
Thanks!

[csporty]

I agree with Steve! The cutout is the biggest problem with a generator. There is no regulation of the charging rate and can over charge and boil the water out of a battery.
An alternator charges at the rate necessary to maintain the battery. While a generator will work adequately on a stock system, you will be marginal when adding turn signals etc.
I changed to a 6v. pos. ground alternator and am very happy with the performance.
If generators and cutouts are so great why are they not in use today?

[Jerry Parr WI]

Well put Kevin. For a long time juice brakes were highly promoted as a solution for poor brakes. Poor being defined as no maintenance in 75 years. We seem to have reached the point where most understand properly restored mechanical brakes work just fine. We have now moved to an era where the alternator is seen as the solution to all electrical problems. Rather than repair/restore the electrical system just change to an alternator.

[Mitch//pa]

an ohm meter is an easy way to check connections and voltage / ground paths for resistance. example put one lead at the battery positive post not the cable clamp and the other to the frame and meter should read 0 ohms.

[Jason in TX]

I would say that if you are visually going to change your generator to an alternator, you should absolutely go with 12V

A 6V ALTERNATOR still won't run a radio, or a CB, or any other accessories. With 12V you can get a jump start from almost anyone, You can find batteries and bulbs all over the place. You can recharge your cellphone.

A 6V alternator looks like a 12V alternator, but by staying 6V all your saving is not having to change your 7 light bulbs and put a resister on the coil.

It's just my opinion, but I say you should go 12V if you are going to put an alternator on a restored Model A.

Things needed for 12V Alternator
- New light bulbs
- Chrysler ballast resister on the coil
- resister hidden in grill shell for the horn.

[Tom Wesenberg]

Originally Posted by A-Jay

If I were to install a 60 amp 6v pos. Grd ALT. are there any other things I would need to do to make it right or better. Also do I want to stay pos. Grd. I would like to have better lights,signals, horn when running, Thanks for your replys.

An alternator doesn't fix anything! It won't fix loose or corroded connections, a dry, never maintained horn, a weak battery, nor poor headlight reflectors. In fact an alternator often leads to more problems, such as too tight a belt for the water pump bearings, and a poorly aligned belt.

The electrical system doesn't care if it gets the 12 amps @ 6 volts from a generator or an ugly alternator. Good reflectors make good light and a horn that's been cleaned and oiled blows like it should. If you add turn signals, that's no problem with it's minor temporary load.

[MrTube]

speaking of jump starting an A. Is there any DC-DC supply on the market that conveniently allows jump starting a 6 volt car off of a 12 volt one?

[roccaas]

Do I remember correctly that "Model A Times" reviewed a Voltage Regulator added to the Generator as a better set up than an Alternator?

Mine came with a 60 NuRex, so I run halogen lights and Cat Eye amber driving lamps. These help because most of my summer driving is done at night when it is not 97 degrees and 95% humidity!

[SteveM]

Originally Posted by MrTube

speaking of jump starting an A. Is there any DC-DC supply on the market that conveniently allows jump starting a 6 volt car off of a 12 volt one?

Exactly the question I had while reading this thread!

Also, I plan to remove my alternator and rebuild the original generator. I'll be selling the alternator when I'm done, but that's not happening for a while.

I'm thinking of going with one of the regulator in the cutout:
http://www.funprojects.com/products/10505r.cfm

Anyone have any experience with these?

Seems like it would eliminate many of the issues with having a generator.

Steve

[Louis]

Originally Posted by A-Jay

If I were to install a 60 amp 6v pos. Grd ALT. are there any other things I would need to do to make it right or better. Also do I want to stay pos. Grd. I would like to have better lights,signals, horn when running, Thanks for your replys.

A-Jay, i put on a pos grd. alt. about 10 mo's ago and it work's great, not one problem. i got tired of hope'ing my gen. was going to work tommorow.
i had it rebuilt, had to take it back for more work the next mo. about a mo. later had to replace the cut-out, with the newer cut-out, it lasted a few week's then i would have to get out and tap on the new cut-out to get it charging agin.
maybe my gen. had been rebuilt to many times over the years??.
my alt. charge's better, the horn work's all the time, the light's are brighter. after starting the eng. in the morn. the amp. guage show's aprox, +6-8 amps for apox. 30 sec's then back to 0 and stay's there.
maybe my gen. was just worn beyound repair, but i would never go back to a gen. JMHO.

[Model A Speedster]

This is a very interesting thread! I'm running 6V alternators on 3 of my A's with no problems. Two of the A's have sealed beam headlights and it's nice to be able to honk your horn and have the lights on at the same time. (That problem - thanks to this thread - may be due to lousy ground paths.) I would recommend that for a driving car you have an alternator. Just my two cents worth...

[Jim/GA]

Originally Posted by MrTube

speaking of jump starting an A. Is there any DC-DC supply on the market that conveniently allows jump starting a 6 volt car off of a 12 volt one?

No.

You need to jump off of another 6 volt vehicle.

Or push it. I find pushing it much easier. Easy to find a couple of volunteers to push on the back bumper and get you moving. Pop the clutch in 2nd gear and you're off. If the only problem you have is a battery that is too weak to crank (or a faulty starter -- which jumping won't help), it will start right up.

[steve s]

The analogy between 6 volt cutout controlled generators and mechanical brakes is solid: If a hundred other niggly little things are all just perfect, both work just fine. The list of potential problem sources is much shorter with 12V alternator and hydraulics; there are good reasons why the whole world switched.

If you do go the alternator route, my advice would be to also go 12V-negative ground. The authenticity and appearance wars have been lost. Might as well get the advantages of easy availability of replacement lights, chargers, batteries, jumps, and accessories, and decreased concern about small voltage drops here and there. You might not think of yourself as someone who loads up his car with goodies, but it's really nice to have the options 12V neg. ground brings if just run a wire and mount an add-on cigarette type electrical plug-in adapter on your firewall or in a kick panel. For example, electric tire/air pump, GPS, hand held spotlight, cell phone charger. You can also get a dealie that plugs in and puts out enough 110 V AC to run a laptop computer or other stuff.

You'll need to get a 12V coil and all new bulbs. I had 12 volt field coils installed in my starter, but many folks insist that's not necessary--you will be amazed to have snappy rather than grunter starting. If you've got the common worn out 6V horn, it may work just fine on 12V; I put a load resistor in the line to mine and it works great.

Steve

[MrTube]

My opinion is you have 2 options. If you want your A to be as close to original as possible "as we do" you keep the 6 volt generator.

If you want to drive your A as a semi modern vehicle, with bright lights, CB's, radios, you use a 12 volt alternator.


Then again, i'm someone who feels a 125A 12volt alternator isn't enough in my cars

An alternator is flat out superior to a DC generator in many ways, from current output, brush wear, voltage regulation and the ONLY reason they used DC generators until the 1960s is they had no way to conveniently rectify high current low voltage AC which an alternator produces.

If they had quality silicon diodes in the 1920s and 30's you can bet your life the model A would've had an alternator.

All that being said, we're keeping a 6V generator on the A because its one of the things that make it what it is, just like the manual timing advance.