It doesn’t take more than a glance at Steve Royster’s 2 HP gearless McVicker engine to know that you’re looking at something pretty rare by gas engine standards. “It’s difficult to find a small tank-cooled engine like this,” says Steve of the engine which dates to between 1904 and 1907. “I got it from Tommy Turner and it had been in Kentucky for a long time. This is the only 2 HP tank-cooled engine that Tommy and I know of.”
As C.H. Wendel explains in American Gasoline Engines Since 1872, McVicker engines were built by Alma Manufacturing Co. of Alma, Mich. The engine utilized a unique valve operating system where no gears or cams were used to activate the exhaust valve. “Instead, a cylinder port permitted a portion of the exhaust pressure to activate the valve,” writes Wendel. “The system was ingenious and perhaps was many years ahead of the times as claimed by the builders.”
Other unique features on Steve’s engine included electric governing, piston-tripped igniter, and rocker arm tripped by a second piston underneath the main piston.