20601 Old State Road Haubstadt, Indiana 47639
In July 1909 Sears, Roebuck & Co. introduced gas engines made at their own factory, the Holm Machine Manufacturing Company at Sparta, Michigan. Two views of these engines taken from the 1909 catalog are shown above. In addition to the same general appearance of the 'Waterloo' Economy, there were other similar features. There is the four bolt wet head with the same intake and exhaust locations. The Witry patent fuel system is used (shown in the previous article). The solid hub flywheels are held tight with a tapered Gib key. The timing gear and gear driven governor are located in the same relationship. The oiler is located on the cylinder behind the water hopper.
The major difference is the speed change mechanism. The 'Waterloo' Economy had the simple Witry patent speed control. The Sparta Economy had the Holm patent speed control which was considerably more complex and costly to build. Holm had applied for patent on his speed control in July 1909, and by the time the patent was granted in October 1910 it was no longer being used. Holm had also left Sparta and returned to Eau Claire, Wisconsin. Sears had gone back to the simple horizontal gear driven fly ball governor with no speed adjustments. More on these first Sparta Economy engines next time.