By the latter part of 1910, Sears, Roebuck & Co. had introduced what is now known as the Sparta Economy Model CA engine. It was just one more step in the gradual metamorphosis beginning with the Waterloo Economy engines in 1907 and continuing through the Model S Hercules-built Economy engines and ending in 1928, when the completely redesigned Economy engines were introduced.
Several changes were made to the Model C -the Holm-developed speed control governor was replaced with a typical horizontal flyball governor with no provision for speed adjustment. During this time, Holm had received a patent for his speed control governor, but Sears never used it after it was granted.
The round side rod was replaced with one made from 3/4-inch square. A new igniter trip appeared and was adjusted with two nuts, one on either side of the igniter tripping mechanism.
The CA models were originally equipped with the Essex fuel mixer, which was soon replaced with the more common Lunkenheimer fuel mixer. Two-bolt flywheels were the norm, but one-bolt flywheels made their appearance in 1912. Toward the end of the CA era, the tag was moved from the side of the water hopper to the front, and the decal ‘Like the Willing Horse’ appeared, which was only used on the ‘off’ side of the water hopper.
Some of the early 2 HP Model CA engines had three bosses on the base, as described in the October 2004 issue. However, a 2 HP engine, with the same dimensions and features, appeared with only a 1-1/2 HP rating. Perhaps Sears was trying to compete in the smaller horsepower market without actually having to offer a physically smaller engine.
Just over 200 of the Model CA Sparta Economy engines are currently said to exist. It is interesting to note that when the newer, slightly redesigned CX models were introduced in 1912, the 2 HP size remained unchanged, and continued as-is until the end of Sparta Economy engine production at Evansville, Ind., in 1915.
Glenn Karch is a noted authority on Hercules engines. Contact him at: 20601 Old State Road, Haubstadt, IN 47639;glenn.karch@gte.net