The Wrights wrote to several engine manufacturers, but none could meet their need for a sufficiently lightweight powerplant. They turned to their shop mechanic, Charlie Taylor, who built an engine in just six weeks in close consultation with the brothers. To keep the weight down the engine block was cast from aluminum, a rare practice at the time. The Wright/Taylor engine had a primitive version of a carburetor, and had no fuel pump. Gasoline was gravity-fed from the fuel tank mounted on a wing strut into a chamber next to the cylinders where it was mixed with air: the fuel-air mixture was then vaporized by heat from the crankcase, forcing it into the cylinders.