An Uncommon HERCULES

Hercules 1 HP model SK engine

Hercules 1 HP model SK engine

Content Tools

20601 Old State Road, Haubstadt, Indiana 47639

The engines built by the Hercules Gas Engine Company are considered rather common, yet even among the common, there is the uncommon. One such case is the Hercules 1? HP model SK engine. There were about 40,000 of these in the regular hit and miss model S built from 1925 to 1929, but to find a 1? HP model SK throttling governed is unusual. I learned about such an engine three years ago when friend George Cad-dick gave me a copy of a 1927 Hercules manual in Spanish. The 1? HP SK was pictured on the second page. I have collected data on about 700 Hercules built engines, but only one 1? HP SK has shown up. I was lucky to purchase it at the 1988 Tri-State swap meet at Portland, Indiana. It was badly rusted with a few parts missing. Fortunately, the necessary throttling governed parts were still there and nearly intact. The side rod was rusted so badly that I cut it into three pieces with side cut pliers to remove it. The water-cooled head was cracked and had a big chunk out of it. Two valve stems were sticking out of the head, but when the head was removed no exhaust valve or stem was found inside.

After disassembling it I transferred the head, fuel system and governor to a disassembled hit and miss engine and had the thing running in four days. On the SK, the head studs, side rod and valve stems are ? inches longer than those on the regular S model. Restoration was begun in January 1989 and finished in March.

From 1925 to 1929, Hercules also built a 2? HP model SK, but none have yet been located. The 1? HP SK was exclusive with the Hercules brand. It was not offered in the Economy, Arco or Jaeger brands.