Double-gear outboard machine

The invention discloses a double-gear outboard machine which comprises an engine. The engine is used for providing torque, an upper gear case is in flange connection with the engine, a bevel gear is in key connection with an output shaft location of the engine and is positioned in the upper gear case, an intermediate case is in flange connection with the lower end of the upper gear case, a lower gear case is in flange connection with the lower end of the intermediate case, a transmission shaft is vertically arranged in the intermediate case, the upper end of the transmission shaft extends intothe upper gear case, a driven bevel gear is in key connection with the upper end of the transmission shaft, and the bevel gear meshes with the driven bevel gear. The double-gear outboard machine hasthe advantages that the horizontal-axis air-cooled engine is used as a power source, the rotational speed of the transmission shaft can be increased by means of speed increase gear transmission, accordingly, the structure of t