Including Economy, ARCO, Jaeger & Thermoil
20601 Old State Road Haubstadt, Indiana 47639
In mid-1928, Hercules introduced a newly designed line of 1? 2? and 3? HP engines. The XI model was a gasoline hit and miss engine. The XK model was throttling governed and could burn gasoline, distillate or kerosene. Both models were offered under the Hercules brand. Sears only offered the Economy XK model. Production of Jaeger and ARCO brand engines had been discontinued by this time.
These X model engines were lighter in weight than comparable size S models that had been offered. They were also from one to five dollars lower in price. The X models were half base engines and were sold mounted on wooden skids. By mid-1930 these X models were discontinued and were re placed by the J model. Sometime in 1930 the 2? and 3? HP sizes were rerated to 3 and 4 HP.
The X model engines retained the same bore, stroke and r.p.m. as the previous S models of comparable horse power.
In addition to the newly designed engines, the 6 and 8 HP sizes were also offered as XI and XK models. The only change from the previous S and SK models was substitution of disk three-hole flywheels in place of the normal spoke type. By 1928 the 10 and 14 HP engines were no longer being produced.
The X models have two easily noticed features. They are half base and are mounted on wooden skids. They have three-hole disk flywheels rather than the spoke type. During 1929 Hercules offered both the S and X model engines, whereas Sears only offered the X model.
In all, a total of some 18,000 X model engines were manufactured during the two year period. About 75% were the Economy brand. Currently, about 90 are known to still exist.
Pictured here is #7776, a l ? HP XK Hercules. It has a January 28, 1929 casting date on it. It belongs to Rudy Hufnagel, an elderly former Hercules employee.