An outboard motor includes an engine, a propeller shaft, a propeller attached to the propeller shaft, a transmission to transmit rotation of the engine to the propeller shaft, an upper accommodation body accommodating a portion of the engine, a lower accommodation body accommodating a portion of the propeller shaft, and a steering to cause the lower accommodation body to rotate about a steering axis with respect to the upper accommodation body. The upper accommodation body includes an upper exhaust channel including an upper exhaust port that communicates with the engine. The lower accommodation body includes a lower exhaust channel including a lower exhaust port. The upper exhaust channel and the lower exhaust channel are switchable between a communication state of communicating with each other and a non-communication state of not communicating with each other based on a rudder angle of the steering.

A method of making a propeller includes forming the propeller to have blades coupled to an outer hub, the outer hub coupled to an inner hub via ribs, and the inner hub configured to be coupled to the marine vessel. The ribs each have first and second ends with a midpoint therebetween, an inner end and an outer end that define a width therebetween, and a leading surface and a trailing surface that define a thickness therebetween. The ribs are tapered such that the thickness is greater at the midpoint than at least at one of the first end and the second end, and scalloped such that the width is greater at the midpoint than at least at one of the first end and the second end. Each of the ribs is coupled to the outer hub in radial alignment with one of the blades.

A method of making a propeller includes forming the propeller to have blades coupled to an outer hub, the outer hub coupled to an inner hub via ribs, and the inner hub configured to be coupled to the marine vessel. The ribs each have first and second ends with a midpoint therebetween, an inner end and an outer end that define a width therebetween, and a leading surface and a trailing surface that define a thickness therebetween. The ribs are tapered such that the thickness is greater at the midpoint than at least at one of the first end and the second end, and scalloped such that the width is greater at the midpoint than at least at one of the first end and the second end. Each of the ribs is coupled to the outer hub in radial alignment with one of the blades.

The invention relates to a blade component for a propeller. The blade component comprises a base which is attachable to a portion of a propeller hub to at least partially enclose the hub and form at least one open ended passage in the hub to permit flow there through. At least one propeller blade extends substantially radially outwardly from the base, and the at least one blade includes a blade face, a blade back, a leading edge, a trailing edge, and a root section connected to the base. An inlet opening is configured on the base which permits flow from the outside to the inside of the enclosed hub. The base or the hub further include a compartment which sub-divides the open ended passage and forms a further water flow passage when the base is attached to the hub, wherein the operatively forward end of the compartment is closed, and the opposing end is open such that water enters the water flow passage through the inlet opening and is directed to flow there through and exit the rear end of the enclosed hub. The inlet opening is configured to run substantially parallel to the axis of the hub, and the inlet opening is further located in register with the water flow passage there below and substantially adjacent to one side of the compartment.

A watercraft propulsion device includes: a motor driving a propulsion unit; a battery supplying electric power to the motor; and a gas flow passage including one end communicating with the battery and another end communicating with a region that is outside a watercraft hull and is located lower than an upper end of a shell panel disposed at an edge of the watercraft hull, the gas flow passage exhausting a gas ejected from the battery from the other end to outside of the watercraft hull.

A watercraft propulsion device includes: a motor driving a propulsion unit; a battery supplying electric power to the motor; and a gas flow passage including one end communicating with the battery and another end communicating with a region that is outside a watercraft hull and is located lower than an upper end of a shell panel disposed at an edge of the watercraft hull, the gas flow passage exhausting a gas ejected from the battery from the other end to outside of the watercraft hull.

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.

A propulsion unit for a marine vessel is adapted to receive power from at least one power supply unit. The propulsion unit includes a stationary part adapted to be mounted to a hull of the marine vessel, and a movable part comprising one or more thrust generating devices adapted to transform the received power into a thrust by acting on water carrying the marine vessel. The propulsion unit is adapted to receive exhaust gases from at least two internal combustion engines, wherein the movable part is adapted to release the exhaust gases into the water.

A propulsion unit for a marine vessel is adapted to receive power from at least one power supply unit. The propulsion unit includes a stationary part adapted to be mounted to a hull of the marine vessel, and a movable part comprising one or more thrust generating devices adapted to transform the received power into a thrust by acting on water carrying the marine vessel. The propulsion unit is adapted to receive exhaust gases from at least two internal combustion engines, wherein the movable part is adapted to release the exhaust gases into the water.

A marine propulsion system configured to propel a marine vessel in a body of water. The marine propulsion system includes an engine and an exhaust system that conveys exhaust gas from the engine. A controller controls the marine propulsion system and includes a memory module that stores operating modes with corresponding sound profiles for controlling the marine propulsion system. An input device is provided for selecting one of the operating modes for controlling the marine propulsion system. Selecting a first operating mode causes the marine propulsion system to sound different than selecting a second operating mode.