Written By Larry Gay
The J. I. Case Threshing Machine Company made its first attempt at a gasoline traction engine in 1892 with a tractor built by William Paterson. However, problems with the ignition and carburetion could not be solved and the project was dropped. The company’s first successful tractor, built in 1912, was the giant Model 30-60 which was powered by a horizontal two-cylinder engine with a 10- x 12-inch bore and stroke. It was soon followed by the Model 20-40 and then the Model 12-25, making a family of three models with horizontal two-cylinder engines.
In 1915, Case started producing the unique Model 10-20, a smaller and lighter tractor weighing only 5,080 pounds with three wheels. The right rear wheel was the drive wheel with a diameter of 52 inches and a width of 22 inches. There was no differential as there was only one drive wheel. The left rear wheel was an idler with the same diameter, but a width of only 10 inches. However, when this unique tractor encountered a soft spot, the left rear wheel could be engaged on-the-go to the live rear axle for additional traction by moving a lever near the operator. The front wheel was in-line with the right rear wheel and was equipped with an arrow on a vertical shaft to help the operator know where it was turned.
Power for the Case 10-20 was produced by a vertical four-cylinder engine with a 4.25- x 6.0-inch bore and stroke. The engine was mounted crosswise on the tractor, between the drive wheel and the front wheel, which enabled the belt pulley on the right side of the tractor to be attached to the end of the crankshaft. The drive train was attached to the left end of the crankshaft and used spur gears to provide a forward speed of two mph. A roller chain drive provided reverse. Although the engine was mounted crosswise, the hood and the right side panel extended lengthwise. The radiator was located on the left side of the tractor, beside the front wheel.
The operator was located behind the right rear wheel and was protected by a fender over the wheel. The steering shaft extended along the right side of the tractor. The Case 10-20 tractor was produced for four years, starting in 1915 and ending in 1918.
Larry Gay is the author of four tractor books published by the American Society of Agricultural and Biological Engineers including Farm Tractors 1975-1995 and Farm Tractors 1995-2005. The four books may be obtained from ASABE by calling 800-695-21723.