alternator required with conversion to 12 volts?
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Topic: alternator required with conversion to 12 volts?
Posted By: Ohio WD45
Subject: alternator required with conversion to 12 volts?
Date Posted: 25 Jul 2011 at 8:12am
| I am looking at a C that the owner has converted to 12 volts. He left the original generator on and says that it will charge just fine. Is this correct? It believe the coil needs to be changed as well. Any thoughts? |
Replies:
Posted By: Lonn
Date Posted: 25 Jul 2011 at 8:20am
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You can have the generator rewired for 12 volt and you need a resistor before the coil or a 12 volt coil with internal resistor. I prefer a 12 Volt coil. ------------- -- --- .... .- -- -- .- -.. / .-- .- ... / .- / -- ..- .-. -.. . .-. .. -. --. / -.-. .... .. .-.. -.. / .-. .- .--. .. ... - Wink I am a Russian Bot |
Posted By: Steve in NJ
Date Posted: 25 Jul 2011 at 8:41am
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If its Mag fired, and there's no other accessories on the Tractor such as headlights, tail, work lamp, etc., the Gennie might keep the Battery just with enough reserve to start it. If you have other accessories that you will be using, or its a Battery Ignition, (which it sounds like if you're talking a coil) the 6V Gennie will not keep the Battery up and the system satisfied with accessory circuitry in operation. When looking at coils with a 12V conversion and 4 cylinder engine, you need 2.7-3.3 ohms of resistance in the Ignition circuit for the engine to run correctly and not eat up the points. A 3.0 ohm coil with built-in resistor is what you want for that application. Universal 12V coils usually are only 1.5 ohms. You need a 3.0 ohm coil to do the job. We have em' in stock, or you can buy one locally at an Auto Parts store. If you go with an Alternator, the 10SI is the most popular. Changing the Ammeter to a Voltmeter would be a good upgrade also for safety. DO NOT use the OEM 3 position switch if so equipped. They do not like the fast moving current of 12V's. Use an aftermarket fused push/pull sw. to control lighting circuits. Other upgrades would include an Ignition sw. and in-line diode to control back feed. HTH If you need any more info, just give a call. Be happy to help you out.....
mailto:Steve@B&B - Steve@B&B 973-632-5596
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Posted By: Gerald J.
Date Posted: 25 Jul 2011 at 10:03am
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The 6 volt generator will generate 12 volts but only when run nearly twice as fast as it generated 6 volts. It can be rewound to generate 12. When running an unmodified 6 volt generator as a 12 volt generator the field coils will run warmer, maybe even hot. I have run a 12 volt generator as a 24 volt motor for hours at a time with no overheating. Its best to use a good solid state voltage regulator for best charging and battery life. A solid state cutout will also improve charging performance over the traditional cutout because the traditional cutout takes nearly 10 amps reverse current before it opens, at least that's what I saw with voltmeter and ammeter in my 1964 VW. Something the voltmeter along won't show. Only an ammeter will show that. While the original ammeter may not survive the current of an alternator, my experience is that the voltmeter is a poorer indication of battery taking charge than an ammeter so long as the alternator or generator is regulated accurately. An ammeter shows the charge going to the battery, while a volt meter (if sufficiently accurate) shows the battery could take a charge if it was connected, but the voltmeter won't confirm that the battery is connected and isn't sufated. Gerald J. |
Posted By: Jeff Z. NY
Date Posted: 25 Jul 2011 at 10:34am
| I could see that coming a mile away with my eyes shut. LOL |
Posted By: Brian Jasper co. Ia
Date Posted: 25 Jul 2011 at 10:52am
If you try to use a 12v regulator on a 6v gen, it will work for a while, but it does make the voltage regulation points not last long. ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Gerald J. wrote:Posted By: Gerald J.
Date Posted: 25 Jul 2011 at 11:48am
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Sometimes a 6 volt will do 12 with just 12 on the fields, but usually the field poles saturate closer to 12 than 12, then it takes more speed to get 12. And running 12 volts on the 6 volt fields doubles the field current which is why the regulator points don't often last. Gerald J. |
Posted By: JimD
Date Posted: 25 Jul 2011 at 12:03pm
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We had a WD with original Genny and it kept the 12V battery at about 13 when running. It had a distributor conversion too. Never ran lights on it. Worked fine the year or so we had it.
JimD ------------- Owner of http://www.OKtractor.com" rel="nofollow - OKtractor.com PM for an instant response on parts. Open M-F 9-6 Central. We have new and used parts. 877-378-6543 |
Posted By: Walker
Date Posted: 25 Jul 2011 at 3:59pm
| The easiest alternator to use is what they call a one wire. Late 60s early 70s GM. Any good Napa man will know when you ask. |
Posted By: Gerald J.
Date Posted: 25 Jul 2011 at 6:23pm
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One wire need to be wired 3 wire on slow speed engines else they won't start charging. Gerald J. |
Posted By: Jerry (Ohio)
Date Posted: 25 Jul 2011 at 7:21pm
| All you need to do is change light blubs and put a resisitor in front of the coil. Have ran many tractors like that . My WC probably 40 years and it is still going. |
Posted By: Jerry (Ohio)
Date Posted: 25 Jul 2011 at 7:33pm
| Sorry about saying the WC. It does not need a resisitor as it has a mag. My WD is what has 12 volts and no mag. Also changed my B & C to 12 volts. Kept origonal gen |
Posted By: Walker
Date Posted: 26 Jul 2011 at 1:33am
| A one wire alternator will charge on a tractor. Ya just use a different pulley. I used the pulley that was on the old generator. Its been on a 52 CA for twenty years, don't tell me it wont charge. I know it will. |
Posted By: Gerald J.
Date Posted: 26 Jul 2011 at 8:18am
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Takes goosing the engine speed to start charging, then it will charge down to idle. There's a better pulley available much smaller diameter than the typical generator pulley for that. Gerald J. |
Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 8:27am
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This is the pulley I use on the single wire alternators.
2 1/2 inch. Comes with a special nut you will need. Gives the alternator more rpms. 
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Posted By: LouSWPA
Date Posted: 26 Jul 2011 at 8:29am
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Like the special nut this forum has? LOL! ------------- I am still confident of this; I will see the goodness of the Lord in the land of the living. Wait for the Lord; be strong and take heart and wait for the Lord. Ps 27 |
Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 8:32am
Did I ever tell you I'm nuts!!!!!
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Posted By: Brian Jasper co. Ia
Date Posted: 26 Jul 2011 at 8:58am
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I thought it was Crazy Harry that was nuts? ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 9:10am
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No, He just has Anxiety Lepidopterophobia.
It's a butterfly thing. 
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Posted By: Ohio WD45
Date Posted: 26 Jul 2011 at 10:26am
| So I guess this has turned into a nature site with squirrels, nuts & butterflies! I just asked a simple question about a alternator! |
Posted By: Lonn
Date Posted: 26 Jul 2011 at 11:39am
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You gotta love it. ------------- -- --- .... .- -- -- .- -.. / .-- .- ... / .- / -- ..- .-. -.. . .-. .. -. --. / -.-. .... .. .-.. -.. / .-. .- .--. .. ... - Wink I am a Russian Bot |
Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 11:52am
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Look up. It was answered.
Don't get all bent out of shape. Life is too short. |
Posted By: Walker
Date Posted: 26 Jul 2011 at 2:36pm
| I'm not here to argue the dynamics of electricity. All I know is the old pulley will work fine and doesn't cost anything. Ask yourself one question. Did you have to goose your late 60s or early 70s automobile to get it to charge? I can start my tractor at idle and it will charge, no goosing, no running to a store for a pulley, it just sits there and idles while it charges. I was merely passing along information to make it simple. Apparently that's not good enough for some. |
Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 3:04pm
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Missing the whole point on some single wire alternators that have not been reworked to exicte at really low rpm's like on small farm tractor engines.
Some single wire alternators charge fine at low rpm's and some need more rpm's to get them exited. Most car engines idle at higher rpms than an Allis B will see running full throttle. Using a smaller pulley let's the alternator get more rpm's at low engine rpm's. I have one that will charge at idle and another that needed more rpm's to excite. When I put the small pulley on it started charging at idle like the other one. Now what's with the attitude????? This is a friendly place to be even if it's just in your mind. Or is it real???? 
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Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 3:22pm
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Have a nice tall glass of iced tea and cool off.
It's hot outside. 
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Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 3:30pm
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No this posts when from squirrels, nuts and butterflies to iced tea.
What's next??? 
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Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 3:32pm
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Posted By: WD45
Date Posted: 26 Jul 2011 at 3:37pm
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Jerry - do you have a part number for the resistor that you are using on the WD. ------------- Fred Dunlop, G,B,CA, WC,WF, 3 WD45`s,gas, diesel and LP,U,D10 series III, D12,D14,D15 SERIES II,D17 Series IV in Gas and Diesel ,D19 GAS and D21,170 185,210 ,220 an I-600 8070 fwd, 716H and 1920H |
Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 3:49pm
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I have used the Mopar one from the 70's cars.
Get them at Napa. Also a 4 post starter solenoid that will bypass the resistor for a full 12 volts while starting the engine. Have most of the tractors with the newer 12 volt coils that has the right internal resistance so you don't need the ballast resistor. |
Posted By: Jeff Z. NY
Date Posted: 26 Jul 2011 at 4:14pm
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Blame Lou and his pissed off cat.
They started it. LOL |
Posted By: Brian Jasper co. Ia
Date Posted: 26 Jul 2011 at 5:02pm
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Before I put electronic ign on my CA, I had a coil that came from a K 301 Kohler engine. Makes a stock looking conversion with no resistor to have to mount, get broken, etc. Was only like $15 too. ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: Jerry (Ohio)
Date Posted: 26 Jul 2011 at 6:54pm
| I doubt that I will find a part # for the resistor. Bought probably 40 years ago. Save your money, for 12 volts all you need is a 12 volt battery and light blubs if a mag engine. For a coil use the resistor |