Abstract: A marine propulsion system is for propelling a marine vessel in water. The system comprises a marine vessel and an outboard motor that is coupled to the marine vessel. The outboard motor has a first inlet that receives intake air for combustion. A second inlet is located on the hull of the marine vessel and a conduit conveys the intake air from the second inlet on the marine vessel to the first inlet on the outboard motor.

Abstract: A marine propulsion system is for propelling a marine vessel in water. The system comprises a marine vessel and an outboard motor that is coupled to the marine vessel. The outboard motor has a first inlet that receives intake air for combustion. A second inlet is located on the hull of the marine vessel and a conduit conveys the intake air from the second inlet on the marine vessel to the first inlet on the outboard motor. The system comprises an outboard motor that is coupled to a marine vessel, and that comprises an exhaust gas relief outlet that is located above the water when the outboard motor is at idle speed. A conduit conveys exhaust gas from the exhaust gas relief outlet to a discharge outlet located on the marine vessel.

Abstract: A marine propulsion system is for propelling a marine vessel in water. The system comprises a marine vessel and an outboard motor that is coupled to the marine vessel. The outboard motor has a first inlet that receives intake air for combustion. A second inlet is located on the hull of the marine vessel and a conduit conveys the intake air from the second inlet on the marine vessel to the first inlet on the outboard motor.

Abstract: A marine drive comprises a gear case housing a vertical driveshaft that rotates a generally horizontal propulsor shaft in a forward direction upon operational engagement with a forwardly rotatable gear and a rearward direction upon operational engagement with a rearwardly rotatable gear. A lubricant exclusion cover is disposed between the forwardly and rearwardly rotatable gears so as to limit churning of lubricant by at least one of the forwardly and rearwardly rotatable gears.

Abstract: A marine drive having a lower gearcase with a vertical drive shaft driving a horizontal propeller shaft in a torpedo housing has a vent plug setting the level of lubricant in the lower gearcase to be substantially at the top of the torpedo housing.

Abstract: The present invention provides a water pump in addition to the impeller system of a marine propulsion system. This allows the water pump to operate independently of the impeller if a clutch is provided which disconnects the impeller from torque transmitting relation with an engine. When a clutch is not provided, the independent water pump of the present invention allows the marine propulsion system to be operated at a lower idle speed than would otherwise be possible because the impeller is not relied upon for a flow of cooling water to the engine.

Abstract: A transparent container (20, 48) is mounted to the inner transom wall (2) of a boat (3) and is connected to the oil passages in a stern drive unit (1). The container is provided with a removable cap (25) having a one-way valve (27) of the Vernay type therein. The valve prevents outward leakage of lubricant fluid from the container, but permits inward passage of air so that, during engine and drive unit cooling, lubricant can be sucked back into the system through the drive housings. The cap may be provided with a lubricant level warning device (41-43; 45-47) which extends downwardly into the container. In another embodiment, the warning device is spaced from the cap and extends upwardly into the container. In another embodiment, the container may be provided with a spring loaded diaphragm (53) which is movably responsive to the lubricant pressure within the stern drive unit.