US Patent 7892054 Outboard motor

An outboard motor includes a water pump arranged to draw in cooling water, a pump drive mechanism that decelerates rotation of a drive shaft and transmits the rotation to the water pump, and an oil supply device (a main oil passage, oil ejection passages, a hollow portion, and an oil ejection hole) arranged to supply oil to lubricate a transmission to the pump drive mechanism. The outboard motor is able to prevent occurrence of cavitation in a water pump of a vane-type pump and to increase a discharge amount of the pump while an engine is running at high speed.