A marine cooling system performs a temperature adjustment of an object to be cooled such as an internal combustion engine of a marine vessel. The marine cooling system includes a water supply flow passage to supply cooling water to the object, a water drain flow passage to drain the cooling water from the object to reduce an amount of the cooling water that contacts the object, and a flow passage controller to shut off the water to the drain flow passage.

A marine cooling system performs a temperature adjustment of an object to be cooled such as an internal combustion engine of a marine vessel. The marine cooling system includes a water supply flow passage to supply cooling water to the object, a water drain flow passage to drain the cooling water from the object to reduce an amount of the cooling water that contacts the object, and a flow passage controller to shut off the water to the drain flow passage.

An outboard motor that significantly reduces or prevents discoloration around an exhaust opening includes an engine, a drive shaft, a propeller shaft, a housing, an exhaust passage, a water intake passage, and a valve. The exhaust passage guides an exhaust gas from the engine toward the discharge chamber inside the housing. The water intake passage guides water, which enters an inside of the housing, to the discharge chamber when a forward propulsive force is generated. The valve regulates passage of the exhaust gas at the first opening due to water pressure when a forward propulsive force is generated. The valve permits the passage of exhaust gas at the first opening due to exhaust pressure when a backward propulsive force is generated.

An outboard motor that significantly reduces or prevents discoloration around an exhaust opening includes an engine, a drive shaft, a propeller shaft, a housing, an exhaust passage, a water intake passage, and a valve. The exhaust passage guides an exhaust gas from the engine toward the discharge chamber inside the housing. The water intake passage guides water, which enters an inside of the housing, to the discharge chamber when a forward propulsive force is generated. The valve regulates passage of the exhaust gas at the first opening due to water pressure when a forward propulsive force is generated. The valve permits the passage of exhaust gas at the first opening due to exhaust pressure when a backward propulsive force is generated.

An outboard motor that significantly reduces or prevents discoloration around an exhaust hole includes an engine, a drive shaft, a propeller shaft, a housing, a discharge passage, and non-metal covers. The housing includes a discharge outlet to discharge an exhaust gas of the engine and the cooling water of the engine. The discharge passage guides the exhaust gas and the cooling water from the engine toward the discharge outlet. The covers are detachably attached to the housing so as to cover the discharge outlet and include at least one exhaust opening.

An outboard motor that significantly reduces or prevents discoloration around an exhaust hole includes an engine, a drive shaft, a propeller shaft, a housing, a discharge passage, and non-metal covers. The housing includes a discharge outlet to discharge an exhaust gas of the engine and the cooling water of the engine. The discharge passage guides the exhaust gas and the cooling water from the engine toward the discharge outlet. The covers are detachably attached to the housing so as to cover the discharge outlet and include at least one exhaust opening.

A supporting structure for an outboard engine. The supporting structure includes an adapter plate for supporting an electric motor having an output shaft for outboard propulsion. Further, the adapter plate supports an invertor for driving the electric motor. The adapter plate includes an output port for fluid tight passage of the electric motor output shaft through the adapter plate.

A supporting structure for an outboard engine. The supporting structure includes an adapter plate for supporting an electric motor having an output shaft for outboard propulsion. Further, the adapter plate supports an invertor for driving the electric motor. The adapter plate includes an output port for fluid tight passage of the electric motor output shaft through the adapter plate.

The invention relates to an outboard engine arrangement, including an electric motor and an invertor for driving the electric motor. The electric motor has an output shaft for outboard propulsion. The engine arrangement further includes an enclosure enclosing a chamber that accommodates the electric motor and the invertor. The enclosure is sealed.

The invention relates to an outboard engine arrangement, including an electric motor and an invertor for driving the electric motor. The electric motor has an output shaft for outboard propulsion. The engine arrangement further includes an enclosure enclosing a chamber that accommodates the electric motor and the invertor. The enclosure is sealed.