These photos show a standard drilling rig utilizing a single-cylinder, two-stroke gas engine manufactured by Bovaird & Seyfang Manufacturing Co., Bradford, Pa. The rig was located in the Bradford Oil Field, and the photos were probably taken in the late 1920s or early 1930s. These photos are from the archives of the Coolspring Power Museum.
This particular Bovaird & Seyfang engine is a 40 HP Class AJ and has a 12-1/2-inch bore by 14-inch stroke. It was fitted with the lighter 900-pound flywheels used for drilling. The pumping engines used 1,200-pound flywheels. The flywheel diameter was 66 inches.
The engine was self-oiling, with the exception of the cylinder, which was equipped with a Manzel mechanical lubricator. Ignition was either by a Wico magneto or hot tube. Like most early Class AJ's, the water pump was a plunger type. Also, no governor was used: The speed was controlled by a telegraph wheel and line to the derrick floor. The forge blower was run by a friction wheel that contacted the clutch side flywheel face. The clutch was of the reversing type.
The rig clearly shows the engine in operation, and one can only imagine the sound coming out of that straight 6-inch exhaust stack pointing at the ground. Note the clutter around the rig. This was typical when the early oil fields were being developed.
Contact engine enthusiast Michael Fuoco at: 656 W. Washington St., Bradford, PA 16701.