12 volt conversion

[dsarge390]

Hello, everyone.

I'm doing the 12 volt conversion over the winter season. Anyone have a preferred vendor to purchase a complete kit from? I'm not interested in fabricating brackets, or piecing several pieces together to save a buck. Thank you in advance.
P.S., no need to convince me to stay with the 6volt system....

[Beater]

what do you need to make brakets for? buy the alternator kit from one of the venders that sells them, the one wire GM style ones, and bolt it on change out your light bulbs, and coil

[dsarge390]

Yes, Beater. Most kits do come with the brackets. Some people make brackets out of spring shackles themselves to save $$. Then buy their own alternator, etc. I'm just not interested in that. That's all I was saying.

[dsarge390]

Has anyone used the kit from Vintage Auto Garage? It looks a little more "original" With cloth wiring and a faux generator, etc...

https://www.vintageautogarage.com/19...t-p/fp2831.htm

[Charlie Stephens]

Remember you can use the original amp meter by running a shunt to carry some of the current.

Charlie Stephens

[Beater]

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well when I did mine I bought the kit from snyders I think. GM delco alternator. brakets all there new pulley ect ect. I changed nothing in the wireing, simply hooked up the wire that used to go to the gen to the alternator. been workin fine


rdit I bought the newrex kit all good so far

[MAG]

Don't forget to convert the starter too. I know you will hear ...."I've been running mine for x number of years"...... But that engaging force of 12 volts on 6 volt coils can and will push the starter ring gear off the flywheel.

[BillLee/Chandler, TX]

Originally Posted by Charlie Stephens

Remember you can use the original amp meter by running a shunt to carry some of the current.

Charlie Stephens

???


I don't understand.


An ampere of current is an ampere of current irregardless of the voltage. The stock amp meter works just fine with a 12v conversion. True, the 20 amp swing is low and switching to a 30 amp meter is often done, but "a shunt to carry some of the current"???? No.

[BillLee/Chandler, TX]

Originally Posted by MAG

Don't forget to convert the starter too........ But that engaging force of 12 volts on 6 volt coils can and will push the starter ring gear off the flywheel.

And the sky is falling......

[Y-Blockhead]

Originally Posted by dsarge390

Has anyone used the kit from Vintage Auto Garage? It looks a little more "original" With cloth wiring and a faux generator, etc...

https://www.vintageautogarage.com/19...t-p/fp2831.htm

I haven't used a kit but the one in your link appears to use the Powermaster PowerGEN, which I do have and is a nice unit. It looks a lot better than the GM one wire also. The GM just doesn't "look right" on a Model A.
If you don't want to chase down the rest of the parts for the 12v conversion individually, then IMO the kit should fill your needs.

[Chuck Sea/Tac]

Originally Posted by BillLee/Chandler, TX

And the sky is falling......

No it’s not, however your ring gear is coming off!

[redmodelt]

If you go with an alternator. They have a smaller pulley so they spin faster at lower speeds, you will also need a clog type belt to fit the smaller diameter pulley. The stock belt is too stiff.

[Patrick L.]

One thing that hasn't been mentioned is that the generator will work fine on 12v.

[Sparky]

Originally Posted by Patrick L.

One thing that hasn't been mentioned is that the generator will work fine on 12v.

Correct, and you can add an electronic regulator to it so you don't need to worry about over-charging. You can even re-polarize the generator for negative ground. (Caveat - an alternator can supply much more power if you really need it)

[Badpuppy]

Originally Posted by Patrick L.

One thing that hasn't been mentioned is that the generator will work fine on 12v.

True. Doubles its power - same current, twice the voltage. Don't know if there's a regulator available for it though. Original cutout might have problems.

Besides battery, coil, bulbs and starter, don't forget the horn and electric wiper motor (if present) will need conversion as well. (I see the above kit includes 2 heating elements to put in series with those. Not efficient, but avoids rewinding.)

[Sparky]

Originally Posted by Badpuppy

Original cutout might have problems.

The original cutout works on 6V only. You will need a solid-state cutout (diode type) or a full regulator (like the one from Fun Projects)

I have a 6V Sparton horn that is wired in series with a 1/2 ohm power resistor.

[Bob Bidonde]

If you call up a reputable Model "A" parts supplier, they should be able to build you a conversion kit. I recommend Bratton's. Be sure to call the dealer because you will have some decisions to make:
> Type of 12V headlights;
> Type of turn signals;
> Type of tail lights;
> Dome light?
> 12V horn?
> 12V to 6V voltage reducers for any 6V accessories you have.


You do not need to do anything with the starter motor. Change the Bendix starter drive to a modern one. The Group 25 battery you will need to buy locally.

[jrelliott]

Why buy the whole kit. As Patrick L said you can use your old generator and a 12V battery. The battery is what determines the voltage our of the generator. If the generator becomes unloaded from the battery will produce up to 40 Volts. You can even change the polarity at the same time by re flashing the generator. You will need the bulbs and a different coil or use a dropping resistor for the coil. Send me our email address and will give you a chart with all the electrical and bulb numbers. [email protected]

[Ernie Vitucci]

Good Model 'A' Morning...Just an observation...Some folks with six volt, ad a second 00 ground strap over to the transmission case and find quite an improvement in cranking speed. Might be worth trying before going to the expense of 12 volt. Ernie in Arizona

[Purdy Swoft]

Patrick L and Sparky are correct . I run my original generator on 12 volts with good results . Though the original type cutout can work , I use the Fun Projects can style voltage regulator that looks the same and takes the place of the cut out . No wires will need to be changed if you continue to run positive ground . If a person wants to change to negative ground , they will need to reverse the wires at the coil and the ammeter . The battery cables will also need to be switched to negative ground if you choose to run negative ground . An original or replacement six volt coil can be used on 12 volts If a resister is used at the coil connections . I prefer the cleaner look of a 3 OHM coil without the need of a resistor. I have used the Pertronix flamethrower coil for hotter spark , quicker starts and more power for better performance . The original starter has worked good for me as well as others . The bulbs will need to be changed and a resister will need to be used on the horn and electric windshield wiper if
used .

There are at least two voltage regulators that can be bused with the original generator on 12 volts. The Fun Projects can style voltage regulator has worked great for me . The Peterson 12 volt voltage regulator that connects at the generator band also works on the model A generator . The voltage regulator that takes the place of the adjustable third brush only can be used on six volts . If a person wants to use the most powerfull halogen head lamps and other high draw accessories they will need to use a 60 amp alternator . Being as all of the 12 volt alternators that are offered in the model A catalogs are negative ground , it will be necessary to change to negative ground if the 12 volt negative ground alternator is used ..

[Y-Blockhead]

Originally Posted by dsarge390

Hello, everyone.

I'm doing the 12 volt conversion over the winter season. Anyone have a preferred vendor to purchase a complete kit from? I'm not interested in fabricating brackets, or piecing several pieces together to save a buck. Thank you in advance.
P.S., no need to convince me to stay with the 6volt system....

Please reread the man's Original Post...

[Charlie Stephens]

Originally Posted by BillLee/Chandler, TX

???


I don't understand.


An ampere of current is an ampere of current irregardless of the voltage. The stock amp meter works just fine with a 12v conversion. True, the 20 amp swing is low and switching to a 30 amp meter is often done, but "a shunt to carry some of the current"???? No.

Bill,

I agree that an amp is an amp regardless of the voltage but that is not the problem. The Model A generator is probably good for slightly less than 20 amps but the proposed alternator puts out 90 amps. I realize that this amperage will not be reached except under unusual conditions. If the fan belt is tight enough to put out 90 amps the water pump bearing will probably soon fail. I do think however that the proposed alternator will be putting out far more than 20 amps on a regular basis. The shunt is an extra wire to carry some the current around the amp meter instead of running all of the current through it. I think that putting far more than the rated amperage through the amp meter on a regular basis would shorten its life but I don’t know this for certain. Original amp meters are hard to find and I haven’t heard good things about the reproductions. The 30-amp unit would be better but it is a current reproduction. I am not sure about its quality and if it is even large enough. I am attaching a picture of the back of the amp meter on my ’32. In this case I have a short coil of wire that approximates the resistance of the amp meter. The result of this additional wire is that the reading will be approximately half of the total current. There is a lot of room behind the dash in a ’32. If I was working with a Model A I think I would run two parallel wires from the alternator to the amp meter, each wire heavy enough to carry all of the load in case of an amp meter failure. I would then connect one wire to each side of the amp meter and and remember that the reading was low by a factor of 2. If the amp meter were still pegging on a regular basis I would fine-tune the system by changing the gauge of the wire that carries the current that goes through the amp meter.

Another concern I have is the original wire on a Model A heavy enough to carry the 90 amps? It might be a good question for the company manufacturing the unit. I would get an answer to this before I went too far. Other questions might be what do they recommend for an amp meter and can they throttle down the maximum output of their unit?

Final thought, why would someone need that many amps in a Model A? I wonder if dsarge390 planning to run electric heaters?

Charlie Stephens

[MAG]

Agree with post 22.
Several Model A's in our tour group are equipped with AC. Consequently there is a large electrical load, approx. 30amp, constantly. That causes the alternator to charge at a corresponding rate. We noticed the ammeter (30 amp)gets very hot to the touch. (one actually failed) We created a shunt to parallel the ammeter which reduces the visible reading to approximately half the actual charge current. They are working well.

[CarlG]

Originally Posted by MAG

Agree with post 22.
Several Model A's in our tour group are equipped with AC. Consequently there is a large electrical load, approx. 30amp, constantly. That causes the alternator to charge at a corresponding rate. We noticed the ammeter (30 amp)gets very hot to the touch. (one actually failed) We created a shunt to parallel the ammeter which reduces the visible reading to approximately half the actual charge current. They are working well.

So, what does your shunt consist of? I tried putting a 22 gauge wire across the back of the 30 amp ammeter and it pretty much zeroed out any readings on the ammeter.

[MAG]

"I tried putting a 22 gauge wire across the back of the 30 amp ammeter and it pretty much zeroed out any readings on the ammeter." Yes Carl, I tried the same thing with the same results.
So, I experimented with about 6 ' of 16gage (insulated) wire and wound it around a short (2 1/2") piece of 3/8" dowel. Wound tightly in two rows with two 6" pig tails and ring tongue terminators on each end. Taped it securely so the coils would stay in place. Connected it on the two terminals on the terminal box on the firewall, paralleling the ammeter. Coil is on the inside of the firewall not seen.

[BillLee/Chandler, TX]

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Avoiding a pi$$ing contest.

[Penthode]

Originally Posted by BillLee/Chandler, TX

???


I don't understand.


An ampere of current is an ampere of current irregardless of the voltage. The stock amp meter works just fine with a 12v conversion. True, the 20 amp swing is low and switching to a 30 amp meter is often done, but "a shunt to carry some of the current"???? No.

I do not understand either. At 12 volts, the current will be one half for the same power dissipation. The current will be less at 12 volts so the same ammeter will be fine.

[Penthode]

Originally Posted by Charlie Stephens

Bill,

I agree that an amp is an amp regardless of the voltage but that is not the problem. The Model A generator is probably good for slightly less than 20 amps but the proposed alternator puts out 90 amps. I realize that this amperage will not be reached except under unusual conditions. If the fan belt is tight enough to put out 90 amps the water pump bearing will probably soon fail. I do think however that the proposed alternator will be putting out far more than 20 amps on a regular basis. The shunt is an extra wire to carry some the current around the amp meter instead of running all of the current through it. I think that putting far more than the rated amperage through the amp meter on a regular basis would shorten its life but I don’t know this for certain. Original amp meters are hard to find and I haven’t heard good things about the reproductions. The 30-amp unit would be better but it is a current reproduction. I am not sure about its quality and if it is even large enough. I am attaching a picture of the back of the amp meter on my ’32. In this case I have a short coil of wire that approximates the resistance of the amp meter. The result of this additional wire is that the reading will be approximately half of the total current. There is a lot of room behind the dash in a ’32. If I was working with a Model A I think I would run two parallel wires from the alternator to the amp meter, each wire heavy enough to carry all of the load in case of an amp meter failure. I would then connect one wire to each side of the amp meter and and remember that the reading was low by a factor of 2. If the amp meter were still pegging on a regular basis I would fine-tune the system by changing the gauge of the wire that carries the current that goes through the amp meter.

Another concern I have is the original wire on a Model A heavy enough to carry the 90 amps? It might be a good question for the company manufacturing the unit. I would get an answer to this before I went too far. Other questions might be what do they recommend for an amp meter and can they throttle down the maximum output of their unit?

Final thought, why would someone need that many amps in a Model A? I wonder if dsarge390 planning to run electric heaters?

Charlie Stephens

This is crazy. The battery charge current should be limited to no more than 10 amperes. At 12 volts, the current usage is one half for the same power. If double wattage headlamps are used, then the headlamp current at 12 volts will be the same as 6 volts.

You will never see 90 amperes through any of the wiring apart from the starter circuit which is heavy gauge wire. 90 amperes will never go through the ammeter: if you attempted to do so, the wiring will likely burn up before the meter!

[Charlie Stephens]

Originally Posted by Penthode

This is crazy. The battery charge current should be limited to no more than 10 amperes. At 12 volts, the current usage is one half for the same power. If double wattage headlamps are used, then the headlamp current at 12 volts will be the same as 6 volts.

You will never see 90 amperes through any of the wiring apart from the starter circuit which is heavy gauge wire. 90 amperes will never go through the ammeter: if you attempted to do so, the wiring will likely burn up before the meter!

You should go back and read the whole thread. The poster is upgrading to 12 volts and an alternator. If the battery is low (maybe he left the lights on when he went to dinner?) when he starts it the alternator will charge at a high rate. Will it be the 90 amps the alternator is rated for? No for several reasons but I m sure it will still be way above 20 amps and this is one scenario where the amp meter needs protection.

Charlie Stephens

[Beater]

Originally Posted by Penthode

This is crazy. The battery charge current should be limited to no more than 10 amperes. At 12 volts, the current usage is one half for the same power. If double wattage headlamps are used, then the headlamp current at 12 volts will be the same as 6 volts.

You will never see 90 amperes through any of the wiring apart from the starter circuit which is heavy gauge wire. 90 amperes will never go through the ammeter: if you attempted to do so, the wiring will likely burn up before the meter!

my speedster has an delco alt update and 12v system. after start up I see the needle over to 30 plus amp for a bit untll the battery catches up ive never added a shunt, might not be a bad idea

[Purdy Swoft]

[QUOTE=Beater;1717430]my speedster has an delco alt update and 12v system. after start up I see the needle over to 30 plus amp for a bit untll the battery catches up ive never added a shunt, might not be a bad idea


Same here . I was told that no shunt would be needed by the vender that sold me the alternator that I use . As long as the voltage regulator is working , it will charge at higher amps until the battery catches up , then the output will drop to about three amps .If there was no voltage regulator in the system, it would charge at high amps all of the time . the alternators that I use have the regulator built in the alternator . The voltage regulator allows the alternator to charge on demand .

[Mike V. Florida]

Originally Posted by Charlie Stephens

I do think however that the proposed alternator will be putting out far more than 20 amps on a regular basis.
Charlie Stephens

What makes you say that?

For the same resistance, the higher the voltage the lower the current.

What would be used on the vehicle that would draw more than the car on 6 volts?

I just looked this up, the most common alternator used for the Model A, the 6 Volt Delco Remy type 10Si series positive ground alternator with self exciting (one-wire) internal voltage regulator can supply 53 amps. Does everyone who uses a 6 volt alternator change out or modify the ammeter?

[Charlie Stephens]

Originally Posted by Mike V. Florida

What makes you say that?

For the same resistance, the higher the voltage the lower the current.

What would be used on the vehicle that would draw more than the car on 6 volts?

I just looked this up, the most common alternator used for the Model A, the 6 Volt Delco Remy type 10Si series positive ground alternator with self exciting (one-wire) internal voltage regulator can supply 53 amps. Does everyone who uses a 6 volt alternator change out or modify the ammeter?

What makes you say that? I say that because in the case when the battery is low (like someone left the lights on) the alternator (or a regulated generator) will put out more current to rapidly charge it.

For the same resistance, the higher the voltage the lower the current. This statement when taken by itself is wrong. I think what you were trying to say is that a system with higher voltage (12) will require less current than one with a lower voltage (6) to do the same amount of work (burn the lights/honk the horn). Please accept my apology if I am trying to put the wrong words in your mouth.

What would be used on the vehicle that would draw more than the car on 6 volts?
You are absolutely right but the draw is not the issue. The issue is that the output of an alternator (or newer generator) will exceed the output of the original generator.

Does everyone who uses a 6 volt alternator change out or modify the ammeter? I am sure that they don't. What I don't know is how long the amp meters will last when stressed by more current than they were designed to be used with. I admit I don't know but I also don't want to find out the hard way. If you have any data from amp meter life versus current tests I would sure like to see it. Otherwise I would rather err on the side of caution, good original amp meters are hard to find.

Charlie Stephens

[Charlie Stephens]

Duplicate post in error - I sure miss that delete button

[30 Closed Cab PU]

From a preceding Post - "For the same resistance, the higher the voltage the lower the current."


Correct me if I am wrong, do not think that is correct.


If using Ohms law - Voltage (V) = Current(I) x Resistance(R). Then Current = Voltage divided by Resistance.


So if Voltage is Doubled with the same Resistance, Current Doubles.


When Converting from 6V to 12 V, the 6V components have to be swapped out with higher resistance 12 V components, or limiting resistors are installed in series with the components to limit current/voltage to the 6V part

[Badpuppy]

With a 12V conversion you should expect half the normal current reading as the 6V. If you add electrical accessories such as AC clutch and blower fans or - Lord save us - electric heaters, you should bypass the ammeter with properly sized wire.

An ammeter should not overheat within its dial range. If it does, the cause is faulty connections either internal or external. Wire terminals should be soldered for best connection. Those hardware store crimpers really don't do it.

[pinball73]

I have already changed my 29 over too 12 volt system & I am still using the 6 volt starter, after changing the starter drive & getting along real good with the set up! the one thing you guys were talking about is a in line resistor for the horn! I have had no luck finding one that will work. I tried a voltage reduction device from speedway & it was too much of a drop in voltage, it would work fine on a constant load but not the horn. my question is where can I get the 3 ohm resistor that you have mentioned?

[Purdy Swoft]

The reason that I change over to 12 volts is not for high draw accessories . I change for the ease of finding 12 volt components such as readily available 12 volt batteries . I use the 12 volt can style voltage regulator from Fun Projects . I set the adjustable brush in the generator for a maximum charge rate of 10 amps . Ten amps is more than enough to run an original type system . I don't need to change over to negative ground so no wires need to be changed.. I use the 12 volt 35 watt halogen bulbs that fit the original sockets . These bulbs are brighter than the original bulbs but not as powerful as the 55-60 watt halogen bulbs that require an alternator and different sockets . This setup looks original unless the battery is seen . Lower amp draw will remove a lot of heat and strain on the electrical system components for longer life and service . For the model A experience , I don't need an air condition or radio . I don't use mine for regular transportation and they are only fun cars . I enjoy the music that my engine makes . If I want all of the modern accessories I will go in the modern car . That is just me and how and why I convert to twelve volts . Its an easy conversion and its still model A with upgrades that don't show .

[BillLee/Chandler, TX]

Originally Posted by pinball73

I have already changed my 29 over too 12 volt system & I am still using the 6 volt starter, after changing the starter drive & getting along real good with the set up! the one thing you guys were talking about is a in line resistor for the horn! I have had no luck finding one that will work. I tried a voltage reduction device from speedway & it was too much of a drop in voltage, it would work fine on a constant load but not the horn. my question is where can I get the 3 ohm resistor that you have mentioned?

https://www.brattons.com/horn-resistor.html

[Purdy Swoft]

The Brattons horn resister would probably be a good choice , especially if you have an original horn . I have read here in the past that an old ignition coil could be used as a horn resister . The coil can be mounted inside the left frame rail so it would be out of site . Maybe someone that has done this will give some input . If the horn isn't original it may not even need a resister . I run the old repro ahooga horns that were sold by JC whitney and others . NAPA sold a version that they called a razz-ma-tazz Horn . I think that Hutchins made these repro ahooga horns . I have run these horns on six or twelve volts . They are nice and loud when used on 12 volts .

[katy]

I tried a voltage reduction device from speedway & it was too much of a drop in voltage, it would work fine on a constant load but not the horn

You could try 2 of them in parallel.

[Mike V. Florida]

I goofed on the ohms law, it is early in the morning. Don't tell my boss, wait I have a union job never mind.

Let me see if I can explain this another way. My house has a 200 amp service going to it. This does not mean that I draw 200 amps. A car can have a 100 Amp alternator but the car will not draw 100 amps just because of the alt.

If the battery is run down to the point that it will accept 90 amps it would not start the car in the first place and the battery would most likely explode, if the main fuse that almost every A owner has installed, did not blow first.

I have never heard of this happening if you have can you cite a source. Nobody in our car club that has a 6 volt alternator has a 30 amp meter in it and none have burned up.

It is your car to do whatever you want to it. If it gets you on the road fine do it.
I'm just saying that unless you are going to add accessories to draw more than 20 amps the amp meter can stay and you can use the money saved on gas to keep you on the road (besides you would need to calibrate the wire you would use as a shunt to properly divide the current if you went in that direction).

The started can no way push off the gear ring as the system is designed.

Again to be crystal clear it is your car do with it as you want, my objection is that someone will make the choices based not on personal preference but on wrong information and even cause damage.

[pinball73]

Originally Posted by BillLee/Chandler, TX

https://www.brattons.com/horn-resistor.html

Thanks guys! I got to have one! been looking for a long time

[30 Closed Cab PU]

Originally Posted by Badpuppy

With a 12V conversion you should expect half the normal current reading as the 6V. If you add electrical accessories such as AC clutch and blower fans or - Lord save us - electric heaters, you should bypass the ammeter with properly sized wire.

An ammeter should not overheat within its dial range. If it does, the cause is faulty connections either internal or external. Wire terminals should be soldered for best connection. Those hardware store crimpers really don't do it.

------------

[30 Closed Cab PU]

Originally Posted by Badpuppy

With a 12V conversion you should expect half the normal current reading as the 6V. If you add electrical accessories such as AC clutch and blower fans or - Lord save us - electric heaters, you should bypass the ammeter with properly sized wire.

An ammeter should not overheat within its dial range. If it does, the cause is faulty connections either internal or external. Wire terminals should be soldered for best connection. Those hardware store crimpers really don't do it.

I believe the current is the same, 6 or 12v.


When converting from 6 to 12, all the loads (coil, starter, lamps, wipers, etc.) have to be updated with 12 V components, or a Series limiting resistor installed on the 6V part.


Essentially; the 12v replacement has twice the resistance of the 6v part, or the series limiting resistor is sized the same as the 6V part and when put in line with the 6V part doubles the resistance of the 6V part for 12 v operation. Eitherway, way current is same: 6V part on 6V, 6v part with series limiting resistor on 12 V, or a 12 volt part on 12V.


An ammeter shunt is only needed when using alternators. They can deliver a max of current of 80-90 amps, pegging a 20 or 30 amp max ammeter. High readings can happen if the alternator is not regulated. Case of high output - short time after starting until the battery refreshes from starting. Longer high output - a partially discharged or bad battery, Halogen lights, lots of optional lights (cowl, fog, etch), air conditioning, etc. A properly shunted ammeter halves the current going through it, and you have to double the reading in your head to get a true reading.


For a long time I had difficulty getting my head around all this, info was spread out and I am not as quick as I once was learning/understanding all this new to me info.

[katy]

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Eitherway, way current is same: 6V part on 6V, 6v part with series limiting resistor on 12 V, or a 12 volt part on 12V.

Not true, when on 12 volt the current (amps) will be 1/2 of the current for a similar part on 6 volt.
If you have a 12 volt 50 watt bulb on 12 volts it will draw around 4 amps.
If you have a 6 volt 50 watt bulb on 6 volts it will draw around 8 amps.
Watts law, watts equals the voltage multiplied by the current in amperes.

[Badpuppy]

^^What katy said. And the resistance of a 12V bulb is 4x that of a 6V of the same wattage: W/V = A, V/A =R. From katy's example, 12/4 = 3; 6/8 = .75.

If you add a series resistor with a device with the same resistance (horn motor) the power dissipation is doubled, since the current must remain the same. The resistor dissipates the same power as the horn in heat, rather than honking.

[Charlie Stephens]

The problem is not the discharge side (unless there have been a lot of changes) but the charge side.

Charlie Stephens

[MAG]

From Post 42.
"The started can no way push off the gear ring as the system is designed."

Are you really sure about that?

[30 Closed Cab PU]

Originally Posted by Badpuppy

^^What katy said. And the resistance of a 12V bulb is 4x that of a 6V of the same wattage: W/V = A, V/A =R. From katy's example, 12/4 = 3; 6/8 = .75.

If you add a series resistor with a device with the same resistance (horn motor) the power dissipation is doubled, since the current must remain the same. The resistor dissipates the same power as the horn in heat, rather than honking.

I see on your public profile you are a retired EE, so either I am having issues remembering theory learned 45 years ago and not used in depth since then(definite possibility), or we misunderstand each other. If fOK with you I will be looking at this more in the next few days, and PMing you - take this off line until I understand. Thanks for being patient, am just trying to understand.

[The Master Cylinder]

I enjoy these long drawn out threads that go way off topic but that is a good thing because maybe I will learn something (or become confused by incorrect info).

Unfortunately the OP has not been back for ~1 week so he can't take advantage of the same...

[30 Closed Cab PU]

-----------------------


Deleted, not sure my calculations used correct coil resistances.

[30 Closed Cab PU]

I have not done the conversion from 6v to 12v , so it is all theoretical. How about getting feedback from member's who have done the conversion. Did current at the Ammeter increase or decrease substantially, or stay about the same?

[Kurt in NJ]

Originally Posted by MAG

From Post 42.
"The started can no way push off the gear ring as the system is designed."

Are you really sure about that?

"as designed" means the ledge on the flywheel is still there , not broke/ worn off due to improper ring gear removal, and a ring gear that fits properly with the proper shrink, and tooth geometry

[MAG]

The ring gear is installed on the flywheel.. front- to- rear. Meaning, with the flywheel lying with the clutch side down, the ring is installed the top side. Pushed on until it reaches the ledge. It is held in place by friction/fit. The starter drive engages the ring gear from the back side. In effect trying to push the ring gear forward; i.e. toward the engine. The starter engaging force is opposite to the installation force.
Saw 3 cases of it last year.
One came completely off.
One came forward enough to cause a severe knocking. The ring gear teeth were hitting the webbing inside the flywheel housing. Drove it back on with a punch and tack welded it in place around the perimeter.
The third one was mine. I noticed it when the starter was removed for 12v conversion.
My ring gear was a new repo. that I installed when rebuilding the engine some 12K miles ago.
Do not know about the other two ring gears.

[jrelliott]

As stated before, running 12V conversion with original power house generator. Had a 12V alternator at first, then went back to 6Volts when I found the Power House. Went back to 12V as easier to find batteries here in the sticks. Wanted a 12V regulator, but Tom Westburg only has a 6V one. I am designing my own and now have the parts to build and test it. Wanted one that went inside the generator to control the field and not like Fun Projects which regulates the current and Voltage afterward.