Hercules Engine News

Hercules Variations

| May/June 2002

  • Hercules Engine Logo

  • Hercules Engine Logo

Over the past 15 years or so, I have assembled a registry of sorts for engines built by the Hercules Gas Engine Co. at Evansville, Ind. The registry starts with engines produced in 1914. At last count there were 3,682 engines on the list, consisting of engines I have seen or have been reported to me.

Many people think Hercules-built engines are simple, look-alike engines. The engines with a 3-1/4-inch bore by 5-inch stroke are, by far, the most common size, and the variations are numerous. There were likely some 140,000 of this size built. The chart at right shows a breakdown of the brands produced by Hercules and the number of 3-1/4-inch x 5-inch size engines on my list to date:

Despite all the variations, you could throw most of the parts into a pile and build up a mix and match engine. This is what makes it hard to properly identify some engines in the Hercules line, because frequently someone has already mixed and matched parts.

Hercules Registry Breakdown/Larger Engines

Bore and stroke

Size HP