B Allis Chalmers

My father owned one of these little tractors that he used on his farm for mowing and raking hay. I have fond memories of driving it when I was a small boy, though at the time I am sure that I complained about having to.

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.

B on trailer, just purchased

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.

When the new bowl arrived, we re-mounted the tank, installed the new sediment bowl, attached the fuel line and added fresh fuel. Success, the engine started right up! But our joy was short lived when we discovered that the engine seemed be be running only over a very limited range of RPM’s. To fast or too slow and it would shut off. Put the throttle at mid-range and it would start right up. And fuel was leaking out the vent in the bottom of the carburetor.

I knew from my youth that the carburetor of a B was notorious for leaking. I don’t think I have ever seen a B that doesn’t have a strain down the side of the engine from leaking fuel. Danny and I took the carburetor apart and found it filled with crud like the fuel tank and sediment bowl had been. Ethanol fuel, especially after it sits for a while, can cause a lot of problems. I thought about ordering a rebuild kit for the carb but was put off by our lack of success in cleaning the sediment bowl.

I did a little research online and found a NEW CARB that was advertised as a replacement for the B so I ordered one. I would recommend this unit, but be forewarned that it takes quite a bit of fiddling to get it fitted to the intake manifold. As the ad states, it has “reversible linkage”. What this translates to is that you have to cut the throttle plate shaft off on the engine side of the carb after attaching the linkage so you can get the carb in place on the intake manifold.

I guess you could leave the shaft sticking out on the outside but I chose to cut it off and file the end smooth. The fuel inlet fitting is also slightly further forward than the original which necessitated fabricating and fitting a new fuel line. The outside diameter of the air inlet on the new carb was larger that the outlet of the air cleaner. While an adapter was provided that was the correct diameter, when it was fitted it wouldn’t clear the air cleaner. I was able to cut the adapter to reduce it’s length but I still had to reduce the length of the rubber hose connecting the carb to the air cleaner. While I was waiting on the carb to arrive, I removed the fuel tank, sanded, primed, and re-painted it. A lot of fiddling, but at last my B was running smoothly!

Another weak point that I remembered was the 6 volt electrical system fed by a generator rather than an alternator. It is a fairly common upgrade to convert to a 12 volt negative ground system with an alternator, so that is the route I chose to take. Quite a few items have to be changed to accomplish the conversion, but none of them are particularly difficult. The first step was to remove the old generator, regulator, and 6 volt battery. A new 12 volt battery was installed but not connected.

I should mention that my B has a distributor ignition, rather than the magneto ignition that most B’s were equipped with. Apparently it was available as an option on the later versions. The ignition coil had to be changed to a 12 volt unit. Be sure to attach the negative side of the new coil to the wire going to the distributor! I removed the fan belt and temporarily attached the battery. The engine cranked right up and ran smoothly so on to the next step.

I had a friend that runs an automotive electrical shop build me up an internally regulated Delco alternator with the body painted black. I also had him install the smallest diameter pulley that was available. I was able to find an alternator mounting bracket that fits the mounting holes for the old generator mounting bracket on E-bay. It was pre-painted and came with all new mounting bolts.

I mounted the alternator and wired it according to a diagram I found HERE. 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”!

Okay, I’ll admit, it’s not much of a dash. I took everything out of the box, sanded, primed, and painted it. An aftermarket voltmeter from the local auto parts shop was installed to replace the old ammeter. I also drilled a new hole and mounted an indicator light as shown in the alternator wiring diagram. I could not find an incandescent indicator light assembly locally, they were all LED. I ended up having to order one online.

A key switch and starter solenoid had been installed by the previous owner. They replaced the original push/pull ignition switch and heel actuator for the starter. I decided to leave them since it would make it easier for my grandson to operate. It was not necessary to replace the starter motor for this conversion. The old 6 volt unit just spins a little faster with the 12 volt system. For intermittent use like a starter it works fine.

Danny gave me a hand hooking up all the electrical, we hooked up the battery, and it fired right up!

I discovered that for some reason it was more difficult to get on and off the tractor than I had remembered from my youth. I installed an aftermarket STEP that makes it much easier. It mounts using existing holes and comes powder coated AC orange.

The steering wheel was in rough shape, with the plastic coating cracked and falling off so I ordered a new one from the local TEMCO store. Just remove the castle nut, pull off the old steering wheel (be sure not to loose the key), install the new one, and tighten the nut. Job done!

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.

I had planned to have the rims sandblasted then prime and paint them but I decided that might not be a good idea given the amount of rust on the front rims. I found a source for NEW FRONT RIMS at a fairly reasonable price. I received a set of these rims and new 3 rib front tires as a Christmas gift from my family. They came primed but not painted, so I scuffed them with a scotch brite pad and painted them.

I gave the paint a couple of days drying time to be sure they were fully cured then had the tires mounted. No more cracked front tires and no more rust, thanks to my family!

For safety, I mounted a stud mounted trailer tail light assembly in the existing holes in the frame under the seat on both sides. They are wired thru a flasher unit that I tie wrapped to the seat frame.

So this is the way my little “B” looks at this time. I still need to get the rear rims sand blasted, prime, and paint them, and of course a new set of rear tires. But these will have to wait on more time and more money!

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2 Comments

  1. Wendy

    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. 🙂

    Reply
    • rick@www.ricksworkshop.com

      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.

      Rick

      Reply

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