6v to 12v model T starter conversion

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6v to 12v model T starter conversion

Post by AdminJeff » Sun Feb 02, 2020 12:40 pm

I'm splitting this topic as it generated lots of PMs and emails. Seems that this topic is of much interest in general.
Scott C. wrote:
Sun Feb 02, 2020 11:04 am
I am curious about your " And I can also do 12v conversations." Can you tell us a little more about that?
Sure. First off, the stock T generator, properly rebuilt and adjusted with a fun projects (or equivalent) 12v regulator will charge a 12v battery. It puts out plenty of voltage and current for the job.

The starter is another story. Put 12v on it and it slams the bendix into the ring gear with a lot of extra force. While plenty of folks have made the case that "I've run my T that way with no issues for years", luck has clearly been on their side. Simple physics and electronics math (V=IR, and P=VI) tells you this this is a recipe for electrical and mechanical disaster over time. It not only puts a lot more stress on the bendix, it puts twice the current through the brushes, armature, wires, field coils, etc. The big losers being the armature commutator and brushes. The field coils can take it, the other components not so much. Sure it'll work for a while, but all additional stress on the listed components will shorten their service life significantly.

So, the solution is to rewire the starter field coils. Stock they are wired in parallel. The 12v conversion wires them in series. Using the equation P=VI,(power equals volts times current) you get half the current when you do that. Thus, when wired in series you essentially get the same stress on all components as if running 6v. This sounds easy, but as I've discovered doing a few of these conversions now, it's a royal pain in the a$$. A LARGE soldering iron, big wire, good insulators, silver based solder and oodles of patience are all necessary to do it right. You also have to get the polarity/magnetism of the poles right on each field coil or nothing works.

I've included a few shots below. The old, used, rewrapped coils ultimately shorted against the housing, but they proved to be a good training and learning ground as this conversion has been attempted by many folks. Some successful, others not so much. After doing this conversion several times now, I've since decided I won't do it unless I start with a new set of field coils. Even when rewrapping the old ones, there's just too much at stake with respect to shorts, so New field coils is the only way to go.

Steve Tomaso just got my last 12v conversation and I don't think he'd mind my quoting him "Starter rolled in yesterday - nice job, my friend ! Very nice job on the brass snout bushing - fits a Bendix drive like a high end leather glove !"

Jeff
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Re: 1919-1927 Completely Rebuilt Ford Model T Generators With 90 day warranty!

Post by Henry K. Lee » Sun Feb 02, 2020 3:04 pm

Jeff da Man! Super Job again!

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Re: 1919-1927 Completely Rebuilt Ford Model T Generators With 90 day warranty!

Post by AdminJeff » Sun Feb 02, 2020 9:31 pm

Thanks Hank! Starters are tricky! Lots of things can bite you, especially when doing all the bushings.

Here’s all my tooling I’ve come up with. I’m not fortunate like Steve Tomaso to have the complete Stevens starter & Generator rebuild kit. Trial and error and lots of reading/studying landed me here.
3F93B7EF-5158-4FBA-9FA9-C3810919540D.jpeg
Tomaso sent me pics of his Stevens kit. I drool over this every day... I think I’ll break this thread off into the general forum. Lots to unpack here...
.
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Modifying Model T starters to operate on twelve volts

Post by Ron Patterson » Mon Feb 03, 2020 8:28 am

Many years ago Chuck Brant and I conducted some instrumented tests to ascertain the operational characteristics of 1.) original Model T starters operating on six volts, 2.) six volt starters running on twelve volts and a six volt starter with the field windings rewired from series/parallel to full series.
Here is a chart depicting the results of those tests for of all three starters.
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Re: 6v to 12v model T starter conversion

Post by Jeff Hood » Mon Feb 03, 2020 11:41 am

I have been running a converted starter for many years and am quite happy with it. I bought a car that had been changed to 12V with an early 60's Ford Falcon generator and regulator and also had some 12V accessories. Rather than change everything back to 6V, I rewired the starter to slow it down and lessen the "hit" that it delivered to the flywheel. As Ron's chart shows (I think,) it still hits the flywheel harder than a 6V, but not nearly as hard as a 12V, and turns faster than a 6V. Anyway, it sounds more like a 6V but turns a little faster, and is easier on the starter, bendix, and flywheel. MHO.


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Re: 6v to 12v model T starter conversion

Post by John Codman » Mon Feb 03, 2020 5:42 pm

I am not pretending to be an expert on this, but my understanding of Ohm's law is that if you double the voltage, you halve the amount of current required to do the same amount of work. In one of the early posts in this thread, someone said that converting to 12V would double the amount of current. I think that it would cut it in half. Please edumucate me on this. Is my understanding of Ohm's law wrong?


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Re: 6v to 12v model T starter conversion

Post by Scott_Conger » Mon Feb 03, 2020 5:51 pm

John

I myself cannot find the reference you are mentioning, but you are correct, current drops with 12V, thus the lighter gauge wire used in the starting motor circuit and elsewhere.
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Re: 6v to 12v model T starter conversion

Post by TonyB » Tue Feb 04, 2020 1:58 am

This is in reply to John....

There are four coils in a Model T starter. If we assume each is 0.1 ohm and wired as two in series and then the pair in parallel, the resistance is surprise —- 0.1 ohm.
Now if we wire all four in series the resistance is 0.4 ohm Everyone following so far?

Ok if we supply nominal 6 volts to 0.1 ohm the resulting current is 60 amps and the power 360 watts

So let’s apply 12 volts to 0.4 ohm, the current is now only 30 amps yet the power is still 360watts

So the current is halved, any resulting power drops to get there are halved yet we have twice the starting voltage. Much more reliable operation with exactly the same power

I leave to the student to apply 12 volts to a six volt starter and why it’s not recommended.....

By the way I disagree with our beloved “assistant to the grand pobar” on the generator. Thr generator can reliably put out 6 volts at 10 amps, equivalent to 60 watts. At 12 volts it will overheat badly if the wattage is increased too much, to say 12 volts at 10 amps. I personally have found generators literally blown apart by heat when this was tried. I have seen experiments to include fans to help cooling without success.
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Re: 6v to 12v model T starter conversion

Post by AdminJeff » Tue Feb 04, 2020 8:54 am

TonyB wrote:
Tue Feb 04, 2020 1:58 am
By the way I disagree with our beloved “assistant to the grand pobar” on the generator. Thr generator can reliably put out 6 volts at 10 amps, equivalent to 60 watts. At 12 volts it will overheat badly if the wattage is increased too much, to say 12 volts at 10 amps. I personally have found generators literally blown apart by heat when this was tried. I have seen experiments to include fans to help cooling without success.
Tony, your expert analysis on current is exactly right, but I never said a stock t generator should or could put out 10amps at 12v... I only said it would work to charge a 12v battery.

I'll expand more fully in that. It is absolutely tempered by charge current. 12v at 5 Amps is the same 60 watts of power (which is ultimately what matters, power generates heat) as 6v at 10A (6v x 10amps=60watts, 12v x 5A=60w), and while clearly not the same 10A charge current at 6v, 5A charge at 12v would certainly work in a Touring situation, but not very well in short trip drives with frequent starter use or driving with the lights always on that would each put more drain on the battery.

As always, your mileage will vary. A lot!

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Re: Modifying Model T starters to operate on twelve volts

Post by AdminJeff » Tue Feb 04, 2020 9:06 am

Ron Patterson wrote:
Mon Feb 03, 2020 8:28 am
Many years ago Chuck Brant and I conducted some instrumented tests to ascertain the operational characteristics of 1.) original Model T starters operating on six volts, 2.) six volt starters running on twelve volts and a six volt starter with the field windings rewired from series/parallel to full series.
Ron, absolutely Awesome, you are the renowned "expert" here for sure! You also just saved me from building a starter Dyno! And those are the approx results I would have expected, although it's really interesting how the graph diverges on rpm VS torque on the 12v series wired conversion graph. It explains why the 12v conversions spin so fast when powered up.

I'm really curious, What instrument/method did you use to measure the torque on the starters?
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Model T generators and Starter measurements

Post by Ron Patterson » Tue Feb 04, 2020 11:09 am

Tonyb
The Model T generator is of a marginal design and capable of reliably producing 100 Watts of power, but NOT on a continual basis (more on this later) . If you continually meet or exceed this capability your generator will ultimately fail.
A 6 volt battery has a 7.2 volts charging voltage. With a 100 Watts generator capability the maximum allowable (more on this later) charge rate would be 13.9 amps.
A 12 Volt battery has a charging rate of 14.2 volts charging voltage. With a 100 Watts generator capability the maximum allowable (more on this later) charge rate would be 7.0 amps.
Now here is the rub:
In the Model T era cars were driven on short trips at low speeds and the generator was not continually producing at its maximum capability. This is why Ford recommended a 14 amp charging rate to keep the battery fully charged with short trips/slow speed.
Today Model T's are driven on longer trips at higher speeds. .....And the world is paved with failed Model T generators with people not understanding why. Driving today requires very low charging rate (5-6 Amps) keep a six volt battery charged.
The poor Model T generator needs all the help it can get and if you keep the charging rate low it will last a long time. Exceed 100 Watts your on borrowed time.
Those are the facts, but here is a tip. In addition to using a low charging rate use a FunProjects voltage regulator which modulates the generator output to the extent the battery actually requires charging. Now the generator is for the most part happily spinning on its bearings producing no output, the generator is not exceeding the 100 Watt limitation and when the battery requires a charge (Just after starting the car or using the headlamps) the battery will be recharged in a few minutes.
If you have halogen headlamps or your wife has connected her hair dryer to your car (or some other power hogging device) all the above does not apply.
But I warn you: continually exceed 100 Watts of power and your Model T generator is not long for this world.

Jeff
Chuck made a simple instrumented Prony Brake to take the starter measurements on the chart i posted.

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Re: 6v to 12v model T starter conversion

Post by TonyB » Tue Feb 04, 2020 12:30 pm

Of course I agree with Ron regarding the power capability if the T generator, his experience coincides with mine very closely.
On one car, the customer really wanted to retain a completely stock appearance but use 12 volts for starting and lites. So I used a modified rebuilt starter and generator with a diode cutout. To keep everything within the power limits, I cut the charge rate down to 6 amps with the third brush and for the most part it worked reasonably well. However this was in the days before LED headlines and the customer was caught in the dark near Yuma and battery ran flat.
My name was mud...
I suppose it might work with LED lites and no other loads but I’m not optimistic. The black Delco alternator is my current choice. 😊
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Re: Model T generators and Starter measurements

Post by AdminJeff » Tue Feb 04, 2020 2:49 pm

Ron Patterson wrote:
Tue Feb 04, 2020 11:09 am
If you have halogen headlamps or your wife has connected her hair dryer to your car (or some other power hogging device) all the above does not apply.

Jeff
Chuck made a simple instrumented Prony Brake to take the starter measurements on the chart i posted.
But my wife demands to use her hair dryer, and she has long flowing hair... oh well..
More GREAT info Ron, now memorialized here for all to learn from.

I was introduced to Prony Brakes in my one required Mechanical Engineering class when I got my EE degree. Too bad I had a major hangover that day and slept through it... I did go to Chico State afterall...
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Re: 6v to 12v model T starter conversion

Post by Luke » Tue Feb 04, 2020 2:54 pm

Tony,

As luck would have it I'm in the process of moving my car over to 12V and LED lighting and have been going through the research/design stage.

By my calculations I'd be needing just on 5A at night with the lights and motor running, so with your customer and similar LED's your name would still have been golden :-)

I'm also going to make my own shunt regulator for the generator, rather than continue with the old-school mechanical cutout that's presently installed.

When I started down the track of my coil tester Mike K made several oblique references to a '$5 DIY regulator'. Now I've no idea what that was about and assumed it was some sort of historic 'in' joke :?: , but at this point, oddly enough, I'm thinking the cost will be in the $5-$10 range, and I'll probably put up the circuit here....

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Re: 6v to 12v model T starter conversion

Post by AdminJeff » Mon Aug 08, 2022 8:46 pm

Updated 12v conversion process.

I recently got a tip from Another forum member on 12v starter conversions. Instead of large gauge wire making the jumper between coils, he used the copper from a old starter coil. I've done several conversions using this technique and can report it is by far the best method I've used, bar none.

A couple of tricks make this a solid solution. I ALWAYS use new field coils when rebuilding starters. It's about the harshest environment you can imagine and old field coils just don't cut it as I offer a 1 year warranty on my starters and I don't like fixing broke. Use old field coils at your own risk.

Separate the new field coils at the middle. Carefully remove the field wires from one of the coil halves. This is not easy and takes some finesse. I use 2 good quality needle nose vice grips and harsh language. The harsher the language, the better the results.

It matters which one keeps the wires... look closely.
.
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Unwrap and clean enough copper from an old coil. 6-8" is good. It needs to be completely straightened, and then polished clean.
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Bend one of the ends using heat and another piece of copper as a template gauge.
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Bend the copper into the general circle form. I use a generator end housing.
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Fit the piece to the starter coils.
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That's the hardest part, and takes the most time. It's tedious, and you have to be patient when fitting the copper.

Next, I use some fiberglass wire heat shield and cover the exposed copper with it.
Then I silver solder both ends in place.
The final piece is to use fiberglass impregnated gasket material to insulate the conductors so the6 don't short out. You could probably get away with wrapping it with fiberglass cloth tape as well. NOT electrical tape. Starters see oil. Electrical tape disintegrates when exposed to oil.
.
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And that's it! Countless hours went into perfecting this process, but I feel that if folks want to attempt it on their own, have at it... we have to pass on the knowledge. This adds several hours to an already tedious starter rebuild process, but done correctly, it should last as long as rebuilt 6v starters.

If you don't want to attempt this yourself, I have one left!
viewtopic.php?f=5&t=19794

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Re: 6v to 12v model T starter conversion

Post by AndyClary » Mon Aug 08, 2022 9:20 pm

Thanks Jeff. Clear and concise. Must be the Idaho wine. 😉

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Re: 6v to 12v model T starter conversion

Post by Steve Jelf » Mon Aug 08, 2022 11:51 pm

But why?
The inevitable often happens.
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Re: 6v to 12v model T starter conversion

Post by AdminJeff » Tue Aug 09, 2022 12:55 am

Steve Jelf wrote:
Mon Aug 08, 2022 11:51 pm
But why?
Yup.... I stopped asking that question long ago. FWIW, my T&A are both 6v and will remain so.
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Re: 6v to 12v model T starter conversion

Post by Tim Rogers » Tue Aug 09, 2022 7:35 am

Great technical thread but "to each their own". The 12 volt superiority myth only serves to damage the hobby.

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Re: 6v to 12v model T starter conversion

Post by TRDxB2 » Tue Aug 09, 2022 9:43 am

Tim Rogers wrote:
Tue Aug 09, 2022 7:35 am
Great technical thread but "to each their own". The 12 volt superiority myth only serves to damage the hobby.
Many have put gone the 12volt route to add extra punch to a week starter/tight engine or out of necessity to complement their use of a 12 volt lighting system.
- Am I correct in thinking that for those who want to add add punch, converting would only put the starter punch back to where it was at 6volts, more or less. Lots of work for no gain either way
The past is a great place and I don't want to erase it or to regret it, but I don't want to be its prisoner either.
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Re: 6v to 12v model T starter conversion

Post by Steve Jelf » Tue Aug 09, 2022 10:15 am

There are good reasons for 12 volts, but starting isn't one of them. My 1915 is for driving, not show, and has a 12 volt mower battery in the trunk. I changed to 12 volts when I installed turn signals and electric tail/brake lights because 12 volt LED's are plentiful and likely to remain so, while the 6 volt ones are scarce and may be on their way out of production. The 12 volt battery is also convenient for a phone charger, navigation device, and tire pump. With Armstrong start, of course, whether the battery is 6 or 12 volts is irrelevant.
The inevitable often happens.
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Re: 6v to 12v model T starter conversion

Post by AdminJeff » Tue Aug 09, 2022 10:41 am

My fascination early in childhood with batteries led me to earn my degree in electronic engineering, so I've spent many, many hours building hundreds of batteries, regulators, measurement systems, and associated circuits. I also have several hundred T starter & generator rebuilds under my belt. Thus, my perspective on this subject comes with that in mind.

I think historically the vast majority of 12v conversions were done to take advantage of better headlight bulbs as good, bright 6v bulbs were non-existent until the recent advent of good 6v LEDs. Today we have a wide variety of LED headlight bulbs and other options in 6v, so that justification isn't valid any longer.

Folks wrongly assume that a 6v starter/battery combination is inferior to 12v. It's not. A 6v starter, properly rebuilt, will reliably crank even a stubborn T to life, if there is a properly charged 6v battery behind it.

So let's look at the root cause of frustration with 6volt systems on our T's.

What is undeniably inferior is the design of the charging system on the T. The generator, properly adjusted and working correctly, is fine, the cutout is not. The cutout on our T's is simply used to stop the T generator from discharging the battery. There is no regulation of battery charging on the T other than adjusting the output of the generator. T generators that are not properly adjusted will invariably over or under charge a 6v battery, and if the car is running, they are always connected. There is very little,if any, control of battery charging when using an on/off switch (cutout sw).

Think of attaching a manual charger on a 12v battery. If you leave it on the battery too long what happens? The battery boils and ultimately fails. This is what your T is doing every time the cutout engages the generator to the battery, which is every time you start the car.

This is why there has been an extremely intense and successful effort to revive the John Regan voltage regulator project. At 217 posts, this thread isn't for the casual reader. But we do solve the root problem...
viewtopic.php?f=2&t=25609&hilit=Regulator

In conclusion, A properly charged and maintained 6v battery will be as reliable and last as long as any 12v system. Address the actual problem (voltage regulation) and drive away happy!

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Re: 6v to 12v model T starter conversion

Post by Novice » Tue Aug 09, 2022 12:12 pm

Six volts will turn the motor over but it won't spin it like 12 volts. But no need to with a engine designed to be hand cranked in the first place.
With six volts there is NO margin for error with loose. poor or corroded connections and terminal lugs. Wires must be heavy duty of the proper gauge and no longer than need be. every inch of excessive cable length robs starter power. "Bigger is better" some times power cables in our hand me down cars have been replaced with lighter gauge 12 volt cables which have excessive voltage drop causing the starter to turn slower with less power. good. cheap 6 volt led headlight and tail lights bulbs are available. But like Steve said 12 volt Leds are plentiful and the supply won't dry up.


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Re: 6v to 12v model T starter conversion

Post by TXGOAT2 » Tue Aug 09, 2022 1:11 pm

As pointed out, wattage (volts X amps) is power to do work, such as cranking an engine. A T generator can produce about 100 watts continuously. A 6 volt T starter in good conditon can consume about 1500 to 1800 watts for 15 seconds or so. A 12 volt starter doing the same work would consume about the same wattage. A 6 volt system, all else being equal, will require heavier gauge conductors throughout than a 12 volt system designed to perform the same work. Most 6 volt systems had the battery located under the floorboard near the starter, probably to limit the cable length.

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Re: 6v to 12v model T starter conversion

Post by Tim Rogers » Tue Aug 09, 2022 1:44 pm

The generator on a stock Model T, as originally designed, does not affect nor is it involved in the engine starting process. The generator's output is irrelevant to operating the starter motor.
<o><o><o><o> Tim Rogers - South of the Adirondacks - Forum member since 2013 <o><o><o><o>


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Re: 6v to 12v model T starter conversion

Post by TXGOAT2 » Tue Aug 09, 2022 1:58 pm

It is if you want the battery to stay charged. A T with no starter has no need of a generator.

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Re: 6v to 12v model T starter conversion

Post by TRDxB2 » Tue Aug 09, 2022 2:16 pm

You can have your 6volts and run 12 volt LED's too, by simply removing the jumper on the back of the ignition switch that connects the BAT power to the coil and the BAT to the lighting circuits. Using a deep charging motorcycle/lawn care/sport battery as a 12 volt source with about enough Ah for your needs. So if you LED light draw 3 amps and you have a 30Ah battery that's about just under 10hours of use (30/3) - 9Ah (9/3 - 3hrs). These batteries are very small. Deep charging batteries can be recharge many times - just get a battery tender or solar charger when on tour.
If you don't have a starter you can leave the jumper in, the buzz coils will run on 12 volts too but distributor coils need to match their voltage
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Re: 6v to 12v model T starter conversion

Post by Luke » Tue Aug 09, 2022 5:28 pm

As long as you have good connections along with healthy cables and starter I wouldn't disagree with many of the comments here regarding 6V vs 12V; it doesn't really matter either way, so whichever floats your boat.

However there are a couple of good reasons to use 12V in my country:
  • The cost of a 6V battery can be more than twice that of a 12V battery, if you can get one
  • The cost and availability of 6V accessories (light bulbs etc) is much higher and less common than 12V
As Jeff mentioned, if you don't properly regulate your charging current then you'll need a battery much more regularly, thus the first point above becomes even more relevant.

So I'm quite happy using 12V, as are many here, however there are also plenty using 6V. Either way I don't see why anyone would get all hot and bothered enough about this to the detriment of their enjoyment of a Model T, and seriously doubt Tim's assertion that
The 12 volt superiority myth only serves to damage the hobby.
Having looked, I have to report that I can find no reliable statistics that would support this statement, and suggest that perhaps it is in itself a myth?


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Re: 6v to 12v model T starter conversion

Post by Luke » Tue Aug 09, 2022 5:39 pm

And, because it deserves a separate post; thanks to Jeff for putting up this latest conversion information.

As he says, it's important to publish this sort of thing for those that will come after us, and while such information may be an anathema to some it will be very useful education to others 👍


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Re: 6v to 12v model T starter conversion

Post by speedytinc » Tue Aug 09, 2022 6:16 pm

Luke wrote:
Tue Aug 09, 2022 5:28 pm
As long as you have good connections along with healthy cables and starter I wouldn't disagree with many of the comments here regarding 6V vs 12V; it doesn't really matter either way, so whichever floats your boat.

However there are a couple of good reasons to use 12V in my country:
  • The cost of a 6V battery can be more than twice that of a 12V battery, if you can get one
  • The cost and availability of 6V accessories (light bulbs etc) is much higher and less common than 12V
As Jeff mentioned, if you don't properly regulate your charging current then you'll need a battery much more regularly, thus the first point above becomes even more relevant.

So I'm quite happy using 12V, as are many here, however there are also plenty using 6V. Either way I don't see why anyone would get all hot and bothered enough about this to the detriment of their enjoyment of a Model T, and seriously doubt Tim's assertion that
The 12 volt superiority myth only serves to damage the hobby.
Having looked, I have to report that I can find no reliable statistics that would support this statement, and suggest that perhaps it is in itself a myth?
Ill add.
If you dont have a strong working magneto, your T will run typically much better on 12V vs 6V.
If you have a hot magneto(or run a dizzy) an up to snuff, stock 6V system is fine.

If you then "need" 12v, you should hand crank OR run a 12V starter or you will damage bendix drives & ring gears. Your generator doesnt care if its charging 12 or 6V, but, back off the output by half to conserve it.

One of my T's runs an 8V battery.(talk about hard to find & expensive!) Why? brighter lights, hotter distributor spark & easier starting hi-compression motor.
Necessary? No. But nice & no hardware changes. All the 6V stuff is rated to 8 volts.

I see too many 12v conversions consisting of a battery, lights & unneeded alternator change. & the starter system gets torn up.
So, if you are doing 12V correctly, (starter modified & generator properly set) No problem IMO.

Whats best? depends on your T.


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Re: 6v to 12v model T starter conversion

Post by Art M » Tue Aug 09, 2022 10:36 pm

Thanks for sharing all of the details and tricks for the converting from 6 v to 12 v. I thought about converting to 12 volts until I cleaned all connections, switch, and the starter. The starter was saturated with engine oil. This happened because I thought more engine oil is better. Now I keep the level at the recommended level.

The wire diagram as shown above must be closely followed in order to provide the proper coil magnet polarity. The wiring looks fairly easy but I don't think is. I have no reason to find out.

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Re: 6v to 12v model T starter conversion

Post by AdminJeff » Wed Aug 10, 2022 10:39 am

Art M wrote:
Tue Aug 09, 2022 10:36 pm
The wire diagram as shown above must be closely followed in order to provide the proper coil magnet polarity.
Yes, extremely important or failure is in your future.
Luke wrote:
Tue Aug 09, 2022 5:39 pm
such information may be an anathema to some it will be very useful education to others 👍
I'm interested to see all the starters where folks try this conversion and ultimately give up!
Sometimes I walk out of my shop at the end of a long day completely defeated. It's mostly when I work all day on 12v starter conversions... sometimes I walk into my shop with the best of intentions to work on 12v conversions and find any excuse not to. I even fixed a leaking toilet in my shop the other day and enjoyed it.

It's getting easier with each improvement to the process but I definitely have to be in the right mood to do battle on this front! I guess I better get my butt outta bed and finish those starters :?
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Re: 6v to 12v model T starter conversion

Post by Luke » Wed Aug 10, 2022 4:39 pm

Jeff,

When you next find this a struggle just think of us here, many miles from the source of all good things T, where we have to strip the coil covers, unwind the copper strip, clean it, anneal it, re-shellac it, rewind over a special form and re-cover in nomex before we can even think of doing anything else...

... and then sometimes if that doesn't work we even have to go deep underground, pick out some copper from a seam, pound it into submission, melt it, roll it, cut it, then carry out the above ;)

Luke.

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Re: 6v to 12v model T starter conversion

Post by Novice » Wed Aug 10, 2022 4:44 pm

Ford sold a 6/12 volt accessory electrical system for trucks in the 50s ? Used for hard winter starting. Had two batteries and a lot of solenoids / relays for the complicated switching involved. I saw one. Don't think they sold many.

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Re: 6v to 12v model T starter conversion

Post by AdminJeff » Wed Aug 10, 2022 7:22 pm

Luke wrote:
Wed Aug 10, 2022 4:39 pm
Jeff,

When you next find this a struggle just think of us here, many miles from the source of all good things T, where we have to strip the coil covers, unwind the copper strip, clean it, anneal it, re-shellac it, rewind over a special form and re-cover in nomex before we can even think of doing anything else...

... and then sometimes if that doesn't work we even have to go deep underground, pick out some copper from a seam, pound it into submission, melt it, roll it, cut it, then carry out the above ;)

Luke.
OK Luke, you win! Ok, my complaints go back in the box...
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