.098 Vertical 2-Cylinder, 2-Cycle Aero Engine

John Swartzwelder's small multi-cylinder aircraft engines. They include: (lower left) .098 opposed 2-cylinder engine; (upper left) .098 vertical 2-cylinder, 2-cycle aero engine; (middle, upper row) .040 opposed 2-cylinder, 2-cycle aero engine; (far right) .020 opposed 2-cylinder, 2-cycle aero engine.

While working in the “wind tunnel” model shop at Boeing, John Swartzwelder, of Washington, fabricated several small multi-cylinder aircraft engines from commercially available Cox .049, .020, and .010 cc model airplane engines. Some were simply geared together via a common propeller shaft and custom engine mount, while others required engineering sophisticated crankcases with specially designed crankshafts. They burn methanol (methyl alcohol) with castor oil mixed in for lubrication. The .098 vertical two-cylinder engine weighs 8 oz.