1919 Allis-Chalmers 6-12

By Staff
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The 1919 Allis-Chalmers 6-12 as found, firmly 'rooted' to the Texas soil.
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Tommy Watson's son Trent removes the bulk of the tree trapping the 6-12.
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Tommy on the finished machine with the replicated one-wheel sulky
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The 6-12 was designed to accommodate horse-drawn attachments with minimal effort.
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The IHC #9 sickle-bar mower.
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The 6-12's LeRoi engine is an integral part of the frame - what little there is. Note the access plate just visible on the outside of the frame above the axle stanchion. Removing the cover gives access for clutch adjustment. A similar, larger plate on the
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A look at the back side of the 6-12 shows the steering gear and the drive for the front wheels. The overall design is a model of simplicity.
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The 6-12 draws admiring glances at one of its first outings.
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Manufacturer: Allis-Chalmers Co., Milwaukee, Wis.
Year: 1919 (years of production: 1919-1926)
Horsepower: 6.27 drawbar, 12.37 belt (Nebraska Test No. 54, 1920)
Number produced: 1,471
Serial number: 10010 (10th unit built)
Engine: LeRoi Model 2-C, four-cylinder, 138-cubic inch displacement
Ignition: Eisemann magneto and spark plug
Cooling: Thermo-siphon
Weight: 2,500 pounds

For more than 20 years, Tommy Watson passed this forlorn tractor on his way to work in rural Texas. A dozer operator, Tommy had worked the land where the tractor sat entwined in a tree.

Ever since he first laid eyes on the machine, Tommy, who hails from Cuero, Texas, knew he wanted it. Tommy knew this wasn’t just any old tractor, but a rare, first-year-production 1919 Allis-Chalmers 6-12. Not only was it a first-year offering, it bore serial no. 10010, making it the 10th 6-12 off the Allis-Chalmers assembly line. However, getting permission to hack it out of its growing casket took some time – 20 years of time, in fact. Finally, on Aug. 15, 2001, after years of trying to make a deal on the AC, he heard the words he’d waited 20 years for: ‘Come and get the tractor.’

That was a lot easier said than done, as the tree the AC was encased in had grown between the tractor’s frame and left wheel, firmly locking the tractor in its woody clutches. Of course, that snafu wasn’t going to stop Tommy, so with the help of his son Trent, Tommy went to work with a chain saw and together they cut the majority of the tree out of the way. The real work started the next day, when Tommy returned with his son Thomas and they literally chiseled the tree from the tractor. With the AC finally freed from the tree, Tommy loaded it up and took it home in order to chisel out the rest of the remaining wood.

Taking stock
Obviously, this was a machine in need of some major work. To begin with, the one-wheel sulky was missing, so the rear of the frame had been sitting on the ground. The engine had a hole rusted through the cylinder head and was pretty much ruined, and tearing the transmission and differential apart showed the machine had seen some hard use: The forward and reverse gears were worn through at least a third of the way through their face.

Further disassembly showed the probable cause of the worn transmission when we found the two clutch discs were completely worn out. Near as we can tell, the last owners had simply tightened the clutch so it wouldn’t slip and then simply banged it into gear whenever they used it. The 6-12 is a simple machine, with only one forward and one reverse gear, so once moving, it doesn’t have cause to shift. I suppose this method could have worked for years.

Tommy was able to find a shop that could weld up the gears, and after looking over the engine a bit more he decided it would be best to replace it.

I took on that chore, logging onto the Antique Tractor Internet Service (www.atis.net) and posting requests for leads and searching through ads. I started to get a little discouraged at one point when I called a fellow in Alabama. After telling him what I was looking for, he said, ‘Hell, you ain’t askin’ for much, are you!’

After posting an ad on ATIS, Paul Strauss, Swartz Creek, Mich., contacted me, and he had the correct LeRoi Model 2-C four-cylinder engine. Paul had acquired the engine when he bought an old cultivator, and we bought it from him. That was the only Model 2-C LeRoi we could find, making me wonder if it wasn’t among the last ones left. We did make one modification, and that was drilling and tapping threads for the priming cups that were installed on the original engine.

Tommy went through the engine and found it in generally good shape. He got a set of rings from Paul Weaver in Bremerton, Wash., and a complete gasket set from Olsen’s Gaskets in Port Orchard, Wash. After a thorough cleanup, valve grind and cylinder honing, he had the engine back together.

The clutches were a problem, as Tommy couldn’t find any specifications telling him how thick they were supposed to be. Texas-based San Antonio Brake & Clutch took on the project of making up new clutch discs, but unfortunately they turned out to be too thick. They made a second, thinner set that ended up working fine.

Amazingly, the AC’s original radiator case was intact, but the tanks and side plates had seen better days. Birchfield & McGee, a sheet metal shop in Cuero, made new tanks and plates using the old ones as patterns, and then Junior at Radiator Service Inc. in nearby Victoria, Texas, put it all back together.

Tommy was still missing the one-wheel sulky, but Bill Orr in Alabama sent blueprints so Tommy could build his own. However, two years later, Bobby McMahan, who bought the property next door to where the AC had been parked all those years, found a piece of iron he thought might belong to the old tractor. He called Tommy, and on July 13, 2003, he loaded it up and brought it to Tommy to inspect. It was the missing sulky. What a stroke of luck! It’s still stuck tight, but at least it’s there if Tommy wants to restore it.

Tommy wanted a period attachment for the tractor, and after some searching he located an old IHC #9 sickle-bar mower. Remember that the 6-12 was designed when many farmers still used horses, so it was crafted to accept various horse-drawn implements. It could pretty much hook up to whatever a farmer had with minimal modifications, and that’s why three different eyes and movable links are available for locating different attachments. The IHC mower adapted easily, and it’s a perfect match for the AC.

I also had the task of coming up with the correct paint for everything. Finding the correct green for the AC was pretty easy, but it was a bit harder trying to nail down the correct colors for the sickle-bar mower. As it turned out, Bill Orr also had color codes for the mower, and with his help we got the correct shades of paint mixed. Well, almost. The one color Bill didn’t have a code for was the ‘IHC Ochre’ used on the mower’s tongue. To get that color, we worked off an old color photo of a #9 sickle-bar mower and got the paint store to match it. It might not be exact, but it’s pretty close.

First run
On Jan. 16, 2003, Tommy fired up the AC for the first time, and two days later, on Jan. 18, he took it for its first drive in who knows how long. He hit the Texas show circuit almost immediately, taking it around the state and sharing it with the rest of the old-iron community. It’s been a hit everywhere it goes, and Tommy plans to continue taking the old AC out to play every now and then.

So far, this is the oldest surviving Allis-Chalmers 6-12 we know of. Another early 6-12, serial no. 10032, is in Ohio, but most surviving 6-12s are from 1920 and later. Production of the 6-12 started with serial no. 1001 in 1919, and by 1926 1,471 had rolled out of the factory. The bulk of these were built between 1919 and 1923, and according to the Unofficial Allis Web site (www.allischalmers.com) only eight were built in 1926.

Contact engine and tractor enthusiast Greg Ray at: 4717 San Jacinto, Houston, TX 77004;gpray@ev1.net

Paint information

Tomato Red (wheels) – Martin-Senour mixing no. 99N-4359, Allis Green (main tractor assembly) – Martin-Senour mixing no. 99L-11511, Safety Yellow (pinstripping and decals) – DuPont no. 29048

IHC #9 Sickle-bar mower
Harvester Red (frame and seat) – DuPont no. 71310, IHC no. 2150, PPG Ditzler no. 71310, Harvester Blue (seat spring, lifting springs, pawl holders and eveners) – DuPont no. 24160, Harvester Cream (wheels) – DuPont no. 43938, Harvester Ochre (drawbar, neck yoke, grass board and grass stick) – no reference available. Locally matched and mixed. Blue Lacquer (cutter bar) – DuPont no. 1150, Martin- M Senour no. 3736

For more information on the Allis-Chalmers 6-12 and otneF AC tractors, check out A Guide to Allis-Chalmers Farm Tractors by Norm Swinford. See the book advertisement on page 71 for ordering information.

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