Abstract: A marine engine comprises a powerhead having an engine block, a cylinder head and a crankcase containing a crankshaft. Operation of the marine engine causes rotation of the crankshaft. A crankcase cover encloses the crankshaft in the crankcase. A supercharger is on the crankcase cover, the supercharger being configured to provide charge air for combustion in the powerhead. The supercharger comprises a charge air outlet for conveying charge air from the supercharger for combustion in the powerhead. A drainage port drains lubricant from the supercharger to the crankcase.

Abstract: First and second oil flow passages are defined in a wall portion of a transmission casing. The first oil flow passage has an open end exposed to an interior of the casing. The second oil passage is connected to the first oil passage through a connection opening defined by the first oil passage. A separate pipe member has a predetermined end portion that is inserted into the first oil passage from the open end of the same. The predetermined end portion comprises a cylindrical portion having a fixed length; an end opening defined by an end of the cylindrical portion and exposed to the first oil passage; and an orifice opening defined by a side wall of the cylindrical portion. The orifice opening is blocked by an inner wall of the first oil passage when the connection opening takes a first position relative to the open end of the first oil passage, and exposed to the second oil passage when the connection opening takes a second position relative to the open end of the first oil passage.