12 volt wiring

converting wd 45 allis to 12 volt  have single wire alt and new coil 12 volt in reduces ..to 6 volt. does anybody have a wiring diagram, or guide me to a source.i have new alt. amp meter,ign switch, and a new light switch.

You should use a voltmeter with the alternator.
The ammeter will not always tell the whole story.

http://www.egauges.com/ATM_Tips.asp?TipPage=voltmeterammeter.htm

I disagree with the voltmeter statement. The ammeter will tell more about the battery condition and its taking charge. The voltmeter will tell you that if the battery was connected it would take charge but it won't tell that the battery IS taking charge. I've run with both and I much prefer the ammeter. The voltmeter is often easier to connect, but really is only of benefit to battery condition if its connected to the battery posts independently of the charging connections, but when its connected somewhere else in the system it doesn't show battery voltage when the battery is being charged or being loaded so its misleading.

Gerald J.

Yea, Gerald has been disagreeing on the voltmeter forever.  I agree with you, Id rather have a voltmeter.  For most of the population that arent engineers a voltmeter will do just fine.    I couldnt resist taken a shot at ya Gerald!!!!!!!!

Here is one that should get you started.

I just looked at Duey's page and I see there is not a diagram there to really help you.

If you can't see the picture well use #10 wire between the alternator and the ammeter and between the ammeter and the hot side of the starter switch or solenoid.
Also the battery cables on the tractor are probably pretty heavy.
You can go to #2 cables.

Yep, the smaller 4ga cables work fine on 12V. My CA has 'em.

re: voltmeter vs. ammeter The voltmeter only shows the voltage in the battery or the alternator, while the ammeter shows the actual charging of the battery or the draining of it.It is easy to have a battery say '12 volts' but not have the guts 'current' to turn over the starter(rrr.rrr.rrr.syndrome)

Put 12 volt on my B .Would not turn enough RPMs to charge. Run wire from alt through switch to ground. I just crank it up flip switch and then cut it off.Wanted small push button but didn,t find one. If you leave switch on it runs battery down  other that it works fine

We have had the ammeter/voltmeter discussion many times before.  There is a good reason that manufactures switched to a voltmeter, and it tells you the same thing if you know what you are looking at.  I don't expect to change the mind of someone like Gerald however;P  Remember that some 12si alternators can put out over 60 amps and most gauges are only rated to 30!

I question from experience the use of any one wire alternator.  They are not a good solution.  I have replaced maybe 2 dozen of them with 3 wire alternators due to failed regulators, inadequate charging at lower rpms for chore tractors, Don't self correct well (undercharge by half a volt) and other general maladies.  If you can return it I would and pickup a 3 wire as they are cheaper, the regulators are more durable, and they charge constantly with the correct voltage If you actually hook up the sense wire.  Running 3 wires is not that hard, exceptionally easy is you buy a kit from Steve. 

JayMiller, I completely fail to see how an ammeter will help you in that situation.   Of course 12 volts will have problems starting a vehicle.  It should read 12.7 volts for a fully charged battery(engine off) and ~14.4 volts when the tractor is running and charging. If you see less then you have issues somewhere, either to great of load or a non/poor functioning charging system, just like an ammeter will tell you.  12V is only a 25 percent charge on the battery, 11.9 volts is a dead battery. 

Jay Moyer

Its a fact Jay. You short out any circuitry that carries Battery power, and yer' gonna have sparks. As far as Voltmeters being safer.. they are! I can shish-ka-bob a 60/60 sweep Ammeter in a matter of seconds on my test bench in the shop with a medium amp (78) 10SI Delco Alternator at full field with 8 gauge wire hooked to it. Why? Because an Ammeter is a flow meter, and you need full power running through it in order for it to tell you something, and that's where the problem lies. Voltmeters splice into the system with lighter circuitry, but still are more accurate and much, much safer than an Ammeter, and that's also a fact. There's no need to run full power through it to tell you what's going on hence the smaller circuitry in the dash. As far as cost between the two gauges? That's BS. In mass production, there isn't any difference in cost, not when the mfr' is buying in substantial volumes, but there is a difference in safety especially if it comes to a head-on collision. Especially in older vehicles that had the main Battery feed circuit running across the radiator support and into the vehicle to an Ammeter.  With today's diesel pickup trucks with dual Batteries, there's even more of an issue, because now there's a one gauge battery cable connecting two high amp Batteries together instead of a #10 gauge circuit.  In a head-on collision there, those two Batteries and its connecting cable are the first thing on the scene of the accident! That could be a real problem! Seen many older vehicles regardless of mfr burn to the ground because the main Battery feed running into the vehicle when grounded, and connected to an Ammeter start things a blazing under the dash. Fully powered up number 8 or 10 wire can really cause a commotion under the dash with insulation when you quickly send that current to ground.  Now yer' talkin' sparks Sir!
You mention Alternators putting out 12 volts at the Voltmeter. If you have an Voltmeter showing 12 volts coming from the Alternator while running, you have a charging problem. Its simple. You don't have to read into anything. Also, a Voltmeter isn't designed to show you what the reserve or capacity is in a Battery. A load tester tells you that. You do the same testing procedures on the Battery if an Ammeter is present in the system also. That particular testing hasn't changed since I've been in the Automotive business. In most cases, failure of a Battery to hold a charge or its capacity is usually a Battery, cable, or connection problem not the Alternator's fault. As I've been preaching on this subject for the past 7-8 years here, and for 40 years being in the Automotive electrical field, most folks could care less what is going in and out of their Battery. They don't know anything about that crap. All they want to know is, is this thing charging or not? Most of the public are not engineers, and that's the other reason Voltmeters are present in vehicles. Simplicity. Voltmeter's are like our Tractors. They're pretty simple. All one needs to know is the normal charging rate of any 12V DC system in their Auto, Truck or Tractor.  If its 12V or below, it isn't charging. If its above 14.5V its overcharging. Either way, it brings attention to the driver and needs to be troubleshooted. When you're working a Tractor in a field, you need to focus on where your going, not trying to figure out whether the Ammeter is showing something going in or going out of the Battery. With a Voltmeter, a quick glance down for a second will tell the driver all he or she needs to know.  To me, that's also safety.......
Steve@B&B

posted this 3 1/2 months ago suprized to see this still being discussed!!!!!!!!!

I just coverted my wd to 12 volt and after much thought of what alternator to use and hating how any of them look on an old tractor I decided to keep the generator and have it converted to 12 volt. no custom mounts and no one would ever know its 12 volt by looking at it. I run a 12 volt regulator and it is one wire hook up with no fear of diss charging by the battery when not running. I love it and am very happy I didn't go the alternator route. I run the stock ammeter and like it but do see how a voltmeter would be safer. However I do understand that the ammeter is way more informative so I prefer it. My next move is to replace the mag with a distributer as mag parts are just to much money and hard to find.