Hot Tube Hercules
This month's oil field engine should be of interest to our own Glenn Karch. It's a 3- HP Hercules Model S, circa 1924-1929, I ran across at the National Pike show in Brownsville, Pa., this past May. This little engine belongs to Bert Simonson, Armstrong's Mills, Ohio, and in its working life it powered a transfer pump that was used to pump oil from one tank to another.
The most peculiar characteristic of this engine is that it has been modified to hot tube ignition and is fueled by gas (propane or natural gas). The majority of the engines used in oil field applications were fueled by natural gas due to its availability as a byproduct of pumping oil. Hot tube ignition was common in oil field engines because the gas was readily available to fuel the burner.
Additionally, given the harsh environment of a remote oil field powerhouse many operators felt hot tube ignition was more reliable than any form of electric ignition. Hot tubes were not susceptible to moisture (in terms of providing ignition), nor did they require the operator to have an understanding of the electrical principles used in magneto-equipped ignition systems. The parts for a hot tube could be fabricated by most anyone, while magneto repairs and parts could be a bit more troublesome. The magneto was also more expensive to purchase.
But hot tubes were not without their weak points. Certainly, they increased the danger of fire, which was always a problem on oil derricks. Also, engine timing was not as accurate as what could be obtained with a magneto-equipped ignition. A hot tube also had a limited lifespan, for in the course of continued use the combination of heat and corrosion would cause them to rupture, something I have personally had occasion to witness. My experience occurred when a few of us were cranking on a friend's engine. The engine emitted a loud 'BANG,' and suddenly we were surrounded by a cloud of white, furry 'stuff.' Once the initial shock wore off we realized the explosion was caused by the hot tube rupturing and the furry 'stuff' floating around was the insulation from inside the hot tube chimney. The good news was that the chimney, which surrounds the tube, contained most of the blast. This is another reason to never look down the top of the chimney at a hot tube while the engine is running - always use a mirror held high and keep spectators at a safe distance.
As an aside, Bert told me that if he had known earlier how well an engine can run on a hot tube he wouldn't have passed up all the good deals he could have gotten on engines with missing magnetos. If you have questions on Bert's hot tube Hercules oil field engine and how his engine is setup he can be contacted at (740) 686-9800.
As always if you'd like a free membership in the Oil Field Engine Society please write to the address below. And don't forget to visit the OFES on-line at www.oilfieldengine.com
Contact the Oil Field Engine Society at: 1231 Banta's Creek Road, Eaton, OH 45320-9701, or e-mail at: oilengine @voyager.net
'The engine emitted a loud 'BANG,' and suddenly we were surrounded by a cloud of white, furry 'stuff.''