Alternator

[Lenny Bruce]

Hi guys was going to install a one wire 6 volt alternator on my tudor. Any recommendations on a good Amp range to go with and or stay away from? I see them from 30 amp and up. Would greatly appreciate any input.

[Bob Bidonde]

Lenny, this may help you decide. I use 60 A alternators in my cars because of halogen headlights, sealed beam fog light, electric windshield wiper motor, heated seats and other modern plug-ins.

[Lenny Bruce]

Thanks Bob! I will upgrade lights as well so that is very helpful

[Badpuppy]

30 amps is plenty for any lighting. Wipers too. Heaters may need more.

[CT Jack]

My "A" has the original 6 volt generator fitted with a solid state voltage regulator. I converted all my lights to LED's including the headlights. The headlight lamps are the more recent Logo lights with lenses. The load or power (watts) demand from LED's are considerably less than incandescent and halogen lamps. The LED's work very well and do not dim at idle with my stock 6 volt generator. I cannot see any advantage with converting the stock electrical system to any other type unless you plan on operating large power consuming devices.

[rotorwrench]

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The only thing I have a problem with on 6-volt conversion alternators is the voltage output. I've not seen any yet that put out less than 7.5 volts. The 6-volt battery lasts longer if voltage is limited to 7.1 volts. I would strongly recommend converting to 12-volts if using an alternator. With twice the voltage, the battery can take a higher voltage level for charging with no ill effects. Light bulbs and components are easily found since 12-volts has been common since 1956. A person can wire in an alternator warning lamp if they choose to which allows the generator to excite immediately. The conversions sometimes take a pretty good amount of rpm for them to self excite on a 1-wire set up.

I had a 6-volt alternator on my old Ford 850 tractor and had problems with it so I changed over to 12-volts with a group 25 battery and it's much more reliable now. I wired it with a generator light in the panel and is excites as soon as the engine is running.

[rfitzpatrick]

Originally Posted by Bob Bidonde

Lenny, this may help you decide. I use 60 A alternators in my cars because of halogen headlights, sealed beam fog light, electric windshield wiper motor, heated seats and other modern plug-ins.

BOB
What kind of mounting bracket did you used for mounting alternator?
Tks

[goodcar]

Originally Posted by Lenny Bruce

Hi guys was going to install a one wire 6 volt alternator on my tudor. Any recommendations on a good Amp range to go with and or stay away from? I see them from 30 amp and up. Would greatly appreciate any input.

I'm ok with my 6-volt 30 amp alternator except that with the higher than 6 volts it puts out, I lose the ahh from my ahhooga horn. I can tweek it some but then it doesn't sound right with the engine shut off. This could be a problem with the horn, I'm not sure. The horn not working right takes a lot of fun out driving.

[nkaminar]

I drove to Mebane (109 miles each way) today to visit other Model A owners. As I pulled into the turnoff for Pete's house I noticed that my ammeter was reading negative (discharge) and the volt meter read 12 volts instead of the usual 14. After some measurements it was determined that the alternator was toast. Colin drove me to the Napa dealer in his 1929 coupe and I picked up a new alternator, off the shelf. We had to change pulleys but nothing more. I would have never made it home without a new alternator. Lesson learned: Having a 12 volt alternator means you can go to Napa or any other auto parts store and pick up a new one.

I am going to fix the old one and keep it as a spare. I have fixed them before. Usually it is just new brushes but sometimes a diode can be burned out.

By the way, the new ammeter showed a charge current for more than the usual time and a higher rate than usual. It took a while to change up the battery and then it went to the usual readings of zero amps and 14 volts.

[Synchro909]

Originally Posted by nkaminar

I would have never made it home without a new alternator. Lesson learned: Having a 12 volt alternator means you can go to Napa or any other auto parts store and pick up a new one.

I am going to fix the old one and keep it as a spare. I have fixed them before. Usually it is just new brushes but sometimes a diode can be burned out.

Agreed and it's not only the alternator. Try buying a 6v coil in out of the way places, light globes the same.
I have spoken many times about our trip into remote areas - trips I wouldn't dream of doing unless I was on 12 v. A CB radio is a must and for those times when phone reception is available, you need the phone to be charged. I haven't seen any 6 volt adaptors for that.

[goodcar]

Originally Posted by Synchro909

Agreed and it's not only the alternator. Try buying a 6v coil in out of the way places, light globes the same.
I have spoken many times about our trip into remote areas - trips I wouldn't dream of doing unless I was on 12 v. A CB radio is a must and for those times when phone reception is available, you need the phone to be charged. I haven't seen any 6 volt adaptors for that.

So, does everyone changing to 12 volts change to a 12-volt starter too?? I know some who jump their cars with 12 volts when their 6-volt battery is dead.
Seems like a potential bomb under your feet.

[rotorwrench]

The starter will rotate at higher rpm but will function on 12-volts. A person can change the fields if they want to but it will work as is.

[nkaminar]

Changing the fields amounts to changing the wiring of the fields from 2 in series and 2 in parallel to all in series. You can buy new field coils for 12 volts or re wire the old ones if they are in good shape. It requires some soldering skill and a good soldering iron. I found the best iron to use is the old style Weller ones with a trigger. They heat fast and you can control the temperature by pulsing the trigger. A good lead-tin solder with a rosin core is best. You may have to go online to get the solder as the ones in the hardware stores are for plumbing and not the 60-40 lead-tin.

A trick to get the iron poles out is to clamp the poles to the case to relieve the pressure on the screws. Do the opposite when re installing the iron poles.

[Synchro909]

Originally Posted by rotorwrench

The starter will rotate at higher rpm but will function on 12-volts. A person can change the fields if they want to but it will work as is.

Yes, it will work but not for long. A 6v starter was running on 12 volts when my brother in law bought his car. I volunteered to convert it to 12 volts for him. I found the armature shaft (the 5/8" one - not the flimsy 1/2" one) was badly bent. I straightened it and did my conversion and it is working well still. I convert using the original field windings rather than buy the new ones form a dealer. I did that with my first conversion but it has failed since. The curvature of the windings wasn't quite right and the insulation wore through against the starter body, causing the fields to short to earth. Result - a dead starter and we were more than 2,000 miles from home!
How has the topic of this thread wandered from alternator to starter motor??