1945 Farmall BN

I have been looking on this site for awhile and finally decided to register.
I have been restoring my 1945 Farmall BN and it is hard to find information. When I first got it in 2002, it had a primer coat and some parts were missing. There was no battery so I bought one and after 12years it went bad. It was sitting most of this years in my shed and now after all these years started restoring it farther. When it was running I never saw any indication that it was charging, the amp gauge stayed at 0. It had a voltage regulator mounted behind the control box on the gas support. I bought a new voltage regulator after going through the tests that someone (forgot his name) posted on here. Indications said it was the voltage regulator. When I first put it on it registered minus with the lights on and not running. Running it went to +5 or so and started coming down. I then read that you are supposed to polarize the generator. I did this and then nothing showed up on the gauge. I called the person I bought it from and said I was sending it back because it did not work. He asked me if I had a 3 brush generator, and I said I did. He informed with that you cannot use a generator (you can but you don't hook up a few things) you need a cut-off. I got one and did polarize it before starting.
Forgot to mention that it originally had a 4 position light switch. I tried lights and amps went to minus -9. Started tractor and amps jumped up to +20, put volt meter on battery and was charging at around 8+ volts.
My question is, why are the amps too high and what could be causing all the amp draw. No lights on, just generator brushes and starter brushes slightly dragging on rotors.

Sorry for such a long post but wanted to explain problem. I put the lights on, two head lights and rear light. They work fine when not running and running on both D and H.

Thanks in advance.

sounds like you have bought a mess. The regulator should be mounted on the generator and the generator
should have the #1101355 or 1101423 on it. Rate of charge is determined by the position of the third brush
and if the 4 position sw is still there the reg will not have a lead going to the sw for hi-charge and ALL
componets in the charging system must have a good ground. The ground cable goes to the positive post. Your
starter should have the #110421 with the sw mounted on top and at the front of the starter and is operated
with a rod thats pushed to start. Over the yrs many things have been changed and were not original so most
of the time they do have their problems. Keeping it original will always work better with less trouble.

It is certainly possible to use a voltage regulator and a 3 brush. If yours will make 20 amps it is a good generator. A cutout must be used with the 4 position light switch. The light switch is internally divided into two parts. One part is a real light switch with a position for Dim beam and full right for Bright beam. (D and B) The low beam is just through a resistor on the switch that makes the front lights dim. The other part of the switch controls the generator output. It is a ground for the generator field circuit. The generator puts out maximum when its field terminal is directly grounded through the light switch body to the switch box and to the tractor chassis. This High output happens when the switch is in H or D or B positions. The L position all the way CCW puts a different resistor in the field circuit. This reduces the output.
Operation: In the daytime, the tractor is started and the switch is turned to H to charge the battery from starting to charged. This in summer is about 10 minutes. In winter, it is more like 20 minutes. The switch is then turned to the left L position, which charges enough to maintain the battery and supply the ignition. Whit the lights on (Dim or Bright) the output accounts for the amps of the lights.
I do not know how it is actually wired, so give us more info. Jim

Thanks to both for your replies. Gene, the starter has the push lever mounted to the top. I had the generator apart and cleaned. The brushes looked good and I cleaned the rotor. I left the brushes where they were when taken apart.

Janicholson. I mounted the cut-out on the generator. The A post is going to the Gen. side of the cut-out. The F post is going to the resistor side of the light switch. The Bat. terminal on the cut-out is going to the Ammeter side that has a jumper going to the fuse side. The headlight wires are going to the top part of the switch with the coil. The tail light is going to the screw by it self on the switch. The Neg. side of the battery is going to the starter and from there to the other side of the Ammeter. Battery wires are #2 wire, light wires are #14 and the others are #10.
I made a mistake in the first post saying the lights on D (dim) and H are working. It should have been B (bright)


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That sounds correct in wiring. to set the output volts on high charge (or D or B) to about 7 volts to 7.3volts (with a needle type analog meter)adjust the third brush away from the fixed brush. 1/8th inch makes a difference. Adjust it only with a fully charged battery. and at 3/4 throttle, Jim

Thanks Jim, when I get it running I will try that. Probably when the weather warms up some. I live in eastern Pa., and it is too cold now unless I put a heater in the shed.
I have the carburetor off which I should have left alone because it was running ok. Put new gaskets in it and it starts but when you shut it off, it will not start and floods. I found out the one set of gaskets did not have the correct body gasket as it covered up the one hole that leads to the choke air inlet. Also the poppet on the choke air shutter was stuck closed and I took that apart and cleaned the brass shaft. There was rust on the disk so cleaned that also.

I hope to just get it to start, run and then shut off and start again. It gets too cold when I open the doors to let the fumes out.