These tractors are quite old, they were manufactured from 1938 thru 1957. According to the serial number mine was manufactured in 1950. The following links will provide some of the HISTORY and the SPECIFICATIONS of the B.
The one that my Dad owned was a very early model, probably pre-World War II. I can remember asking about what appeared to be a very small additional fuel tank on the right side, in front of the main fuel tank. He told me that originally the small tank held gasoline while the main tank was filled with kerosene. The tractor would be started on gasoline and allowed to warm up, then switched over to kerosene, which was much cheaper at the time. He also mentioned that the tractor originally came equipped with hand brakes and no electrical or hydraulic systems. The simple electrical system (battery, starter, generator, and lights), foot brakes, and hydraulics (pump, valve, single acting cylinder) were added through the years.
I thought it would be nice to purchase a “B” and restore it for my grandson to drive around. What follows will be the story of that restoration.
This is a picture of the B that I ended up buying, still sitting on the trailer the day I brought it home. That’s my son-in-law Danny and my grandson Alex checking it out.
When I had first started talking about restoring a “B” Danny shared with me that his grandfather had taught him to drive a “C” when he was young.
I had looked a quite a few examples before finding this one. Lots of the ones that I saw for sale were in pretty rough shape from years of neglect. I found this particular tractor on my local Craig’s List. It looked good in the one photo with the ad but I had learned that a photo can be misleading. I tried to contact the seller but did not get a response, so I continued my search. A few weeks (and several tractors) later I noticed the ad was still on Craig’s List so I tried contacting the seller again and asked that they call to let me know if the tractor was still for sale. Late that afternoon I got a call advising that it was still available.
The owner said he and some friends had cleaned it with a steel brush and had it painted. Both fenders, battery box, oil pressure and water temperature gauges, and seat cushion were new. The tractor had been stored inside and not run for several years. My wife and I took my trailer and drove over to the sellers location, about 40 miles from our home.
It had what I like to call a 20 foot paint job, it looked good from a few feet away, but a lot of flaws were evident upon close inspection. The tires were all cracked and dry rotted. The engine turned and seemed to have good compression but would not start. But, it was all there and in fairly decent condition. We agreed on a price and I loaded it onto the trailer. I was the owner of a B Allis Chalmers!
The next week I called a friend who was into antique tractors and got him to come by and see if we could get it started. I had called Ray on my cell phone while I was running some errands and by the time I got home he already had it running. Turns out the points were stuck closed. But it would only run at idle, and just for a few minutes. So, I unloaded it and got it into the garage of my shop. I knew the gas was old so I took the sediment bowl off to drain the fuel. All that came out was a few drops at a time. No problem, I thought. I’ll just remove the sediment bowl assembly from the fuel tank. Still no luck! So, on to plan B.
I got Danny to help remove the fuel tank and we dumped the stale fuel out the filler opening. Then we took a brass brazing rod and broke loose all the crud from the fitting on the bottom of the tank. Then we stapled a scotch brite pad to the end of a wooden dowel and used it to scrub all the interior areas of the tank we could reach. Then we flushed the tank with the stale fuel to get the debris out, followed by a flush with a small amount of fresh fuel. We couldn’t get the crud out of the passages of the sediment bowl so a new one was ordered. So far, so good.
I mounted the alternator and wired it according to this diagram. I added a new 10 gauge wire from the alternator output back to the battery cable terminal on the starter solenoid because of the higher current output of the alternator. Progress is being made, on to the “dash”!
Danny gave me a hand hooking up all the electrical, we hooked up the battery, and it fired right up!
As I said in the beginning, the tires were all cracked and dry rotted. One of the front tires wouldn’t hold air when I bought the tractor. I took it to a local shop and had a new tube installed. The rim was so rusted on the inside that they had to wrap it in duct tape to prevent the rust flakes from puncturing the new tube.
Thanks for the info. I’ve got a 1943 Allis B which I’m wanting to covert to an electric start. She’s crank start at the moment and can be quite a chore for me when she doesn’t want to play ball… I’m having trouble tracking down a starter kit in the UK, if you can give me any suggestions where to start…plenty of parts in the U.S.A but pricey postage.
Regards, Wendy. 🙂
Sorry to hear that you are having troubles hand starting you B. Usually they start easily when properly tuned.
As far as adding electric start, I believe the changes required are quite significant. From what I can discover, the frame casting to the rear of the engine, called the torque tube, must be replaced. Also the flywheel would probably need to be replaced with one with a ring gear. All this in addition of the battery box, battery, starter,generator or alternator, and all the associated wiring.
I would be tempted to try a thorough tune up first. If you are still interested adding electric start I would be glad to help you try to track down the necessary pieces.
I have an A-C 1939 B model
it starts on the crank handle ,
Do you know in which year the factory introduced the starter motor to the tractor.
I do not have any first hand information, but according to the discussion on the Allis Chalmers Forum starting in late 1939 or early 1940.
I have a Allis Chalmers 1948 tractor, ID no. C 26058..
How does the positive and negative cables go.
Is it still set up for 6 volts or has it been converted to 12 volts?
If it is still 6 volts, it will be positive ground.
If it has been converted to 12 volts , it will be negative ground.
Hope this helps. Good luck
I have almost completed my 1948 b allic. I have owned it for 25 year’s took it apart sand blasted front hood, tank.look good. New carb. Just like you cut the bolt on back. Changed to alternate gauge like you. Put a refused from 12 down to six to coil.still trying to get wired correct. But it run like new.
Sounds like you have been doing good work on your B.
If I can be any help with the wiring let me know.
I like where you have spent money on that b. Didn’t waste a dime in my opinion. That Allis will be around a long time. I have a d15 and fix up now and then. A little attention goes a long way on these old tractors.
I have a 1939 AC model B, it’s crank start with a magneto. Would like to add headlights, do you have any suggestions on how to do this? Can I tie them into the magneto or do I need to add a 12 volt battery and generator?
I am afraid you cannot use the magneto to power headlights.
The magneto is designed to generate a high voltage pulse
that is connected to the coil to energize the spark plugs.
If you want lights you will need a generator or alternator,
voltage regulator, battery, lights, and associated wiring.
The alternator with internal voltage regulator like I upgraded
to would probably be the easiest.
If you have any more questions I would be glad to try to answer them.
Did you have to use a resistor for the coil? I’ve heard you have to so the points won’t burn out however that statement is from people who haven’t done a conversion.
I purchased a 12 volt coil so no resistor required. Be sure to use the correct polarity when connecting the coil.
Beautiful job, and your information and presentation was great. I inherited a AC B and an AC WD45. The 45 still runs like a top, the B just needs work. The pictures were very helpful!
Thanks for the comment. My Dad had a WD on the farm when I was growing up.
He purchased the WD and a Rotobaler (early round baler) at the same time.
I hope you enjoy your tractors and good luck with the B.
I have a 1938 AC B. The fuel tank is all rusted out. Any suggestions for repairing it? Or do you know where I could get a replacement? I am in California.
Hi Gloria, I really would not recommend trying to repair. You might try http://www.yesterdaystractors.com for a replacement part.
J have a Allis Chalmers tractor I’m not sure if its B or C how can I tell?
Hi Gene, Sorry for the delay in responding, been on vacation.
Don’t know much about the C, but every one I ever saw had narrow “tricycle” front wheels while the B had wide front wheels.
I have a 1945 allis chalmers C . It runs very well however, the other day it started right up then died when I tried to get it started again it wouldn’t do anything, no sound or anything. The battery is fully charged, so I thought it might be the starter so I had it checked. I then checked the wiring connections for corrosion, still nothing. Does anyone have any suggestions?
Great restore! I was given a 1945 B from my Dad. He had one growing up on their small farm. It runs great, however it is all of a sudden draining the battery. The switch for the Headlights is off as far as I can tell. I would like to eventually convert to 12V but for time being am trying to figure out what keeps draining the battery. If i put the multimeter on it i can literally watch the voltage drop. Any ideas? Thank you
Sounds like you have a serious drain on the electrical circuit.
Have you checked the voltage regulator for stuck or burned contacts?
Probably has original rubber/cloth braid wiring so be sure to check
for frayed wiring, especially at penetrations thru metal parts or at clamps.
this is a great source of info! i just picked up my first vintage tractor, in fact i got two, they are both B models, one is a 1940, the other is a 1944. Should i be running leaded gas in them or is unleaded ok?
I have been using unleaded without ethanol with no issues.
Of course, I don’t run it very often.
I do not know what type fuel my dad used, there was a 500
gallon tank on the farm that was used to fuel the B and a
WD with. I know it was “regular” grade fuel, so given the
time frame, it was probably leaded.
I have the same Allis Chalmers B tractor. Mine in from 1952 my dad left me to brush hog the fields. Do you sell parts? Or where do u order parts from? I’m from Western NY. It needs an alternator
Sorry, I am a hobbyist, don’t sell parts.
You might try http://www.yesterdaystractors.com for parts.
The B came with a generator and a 6 volt electrical system.
If yours is equipped with an alternator it was probably
converted to 12 volts and the alternator at some time.
Your best bet might be an independent auto electric shop.
I have noticed with mine sometimes I have to run the engine
at high RPM for a few seconds to get the alternator to start
charging, then reduce to whatever speed you desire.
Good Luck with your B.
Great article and a real beaut machine there Rick 🙂
I don’t have a B at present but having grown up with WDs and WCs I enjoyed immensely the detail and pleasure of this restoration. Hopefully I can do a restoration of my own someday.
I’m glad you enjoyed the description of my restoration.
I need to get around to updating it with the remained of
the work I have completed, mostly powder coating the rear
rims and installing new rear tires. Hopefully I will have
an opportunity to do the update soon.
Nicely done. Will be checking back for updates. Thanks for sharing.
Glad you enjoyed it!
I enjoyed the description of your restoration. I have a 1939 AC Model B which I bought in 1984 when I first moved out into the country. I’m just a “hobby farmer” so it continues to serve me well when I need it. Mine starts by cranking and it usually starts fairly quickly. The great part about the magneto version is that there’s no battery to go dead over the winter when I’m not using it. I’m in the middle of trying to change the fuel sediment bulb but it isn’t as easy as I’d hoped. I finally found a correct size wrench to remove it but it’s too close to a bracket (I think it holds the fuel tank in place) to turn the sediment bulb assembly past the shut-off valve. Do I have to remove the tank to do this? Thanks.
I had the fuel tank removed when I replaced mine. All you need is a large flat blade screw driver to remove the tank. Just loosen the slotted bolt and remove the retaining strap and it lifts right off. Good luck.