Patent ID: 6484681
Filing Date: 2002-11-26
Classification: F02B

Abstract:
An outboard motor comprising:a mount case; an engine which includes an engine body mounted to said mount case with a mount wall portion of the engine body and defining a crank chamber containing a vertically extending crank shaft and bearing portions rotatably supporting the crank shaft, an intake valve and an exhaust valve for opening and closing an intake opening and an exhaust opening, respectively, which open to a combustion chamber; a valve driving mechanism for opening and closing the intake valve and the exhaust valve; at least one of said intake valve and said exhaust valve including a plurality of such valves for each cylinder of the engine; said valve driving mechanism including a hydraulic-driven valve operating characteristics variable mechanism which changes operating characteristics of at least one intake valve or exhaust valve among said plurality of intake valves or exhaust valves in accordance with the revolution speed of the engine; an oil pump driven by said engine; an hydraulic oil path for supplying said valve operating characteristics variable mechanism with hydraulic oil being branched at a branching portion from a lubricant oil path for supplying said bearing portions and said valve driving mechanism with lubricant oil released from said oil pump; said branching portion being formed in a wall portion of said engine body other than said mount wall portion; and an hydraulic control valve for controlling pressure of hydraulic oil at said branching portion.