Hercules Engine News

Unraveling Differences in Hercules 3 HP Engines


| October/November 2001



Finding more information out about the Hercules-built engines is always a continuing challenge. There is bound to be more information out there because there are a number of questions yet to be answered - and new things keep popping up.

Just recently I acquired a 7 HP half base Hercules-built engine from Larry Paschke that reportedly had been used on a hay baler. Surprise; although I didn't notice it at the time, the half base has turned out to be different than the normal early half base that was adapted to the old, straight-framed cart. A continuing story on that engine will be forth coming.

A message came a few days ago about a 7 HP EK Hercules engine that came factory supplied so it could be run as a hit-and-miss or as a throttling governed engine. Hopefully, Tom Weatherford will supply more information on that one.

Tom Bellar asks questions about his 3 HP Hercules engine. Although the tag indicates it is a 1919 engine, the head has a 1926 casting date on it. The 3 HP size (variously rated at 2- to 3-) has several variations when it comes to the head, water hopper and oiler location.

Although the physical appearance is similar, it is a little tricky to match up some parts, especially if the engine is supposed to be correct when it is finished. The 2- HP E Economy had a 4-inch bore. The early 2- HP Hercules had a 4-inch bore, but the 3 HP Hercules and later 3 HP Economys had a 4--inch bore. Some of the 3 HP EK Hercules had a 4-inch bore. That all sounds complicated. The 4-inch bore heads will fit the 4--inch bore engine, but not vise versa, although the bolt patterns are identical.

Bellar observes that there are only two water ports in the head that match up with the five water ports in the block. Most of the time, there are three matching water ports. Since none of the water ports are at the bottom of the head, it is necessary to take the plug out of the bottom to completely drain it. I once had a 5 HP Thermoil that had only one matching water port. Now you know why there are so many cracked heads. The petcock under the cylinder doesn't fully drain the head.