An outboard drive device (10) comprising a motor (11) having a crankshaft (16), wherein said outboard drive device (10) further comprises a propeller shaft (12) with a propeller which propeller is below the hull (13) of a boat when said outboard drive device (10) is operated, and a power coupling system for transferring power from the motor (11) to the propeller shaft (12). The motor (11) is an automotive motor or an industrial base engine, wherein the crankshaft (16) is substantially horizontal and substantially parallel to the propeller shaft (12) when said outboard drive device (10) is operated. The power coupling system comprises a power transfer device (17), a transmission (18) and a transmission drive shaft (19). The power transfer device (17) connects the crankshaft (16) with the transmission drive shaft (19) for transferring the output power from the crankshaft (16) to the transmission drive shaft (19). The transmission (18) comprises a forward gear (23) and a reverse gear (24), so that the output power is reversible.