A marine propulsion system includes a marine propulsion device, a battery, and a controller. The marine propulsion device includes a propeller shaft, an engine, and an electric motor. The marine propulsion device transmits mechanical power from at least one of the engine and the electric motor to the propeller shaft. The battery supplies electric power to the electric motor. The controller controls the marine propulsion device such that the marine propulsion device is switchable among drive modes including a first drive mode and a second drive mode. In the first drive mode, mechanical power is transmitted from only the engine to the propeller shaft. In the second drive mode, mechanical power is transmitted from only the electric motor to the propeller shaft when the engine is in an idling state.

The invention provides an internal combustion engine comprising a piston mounted for reciprocating linear motion within a cylinder along a cylinder axis. The piston is coupled to an output shaft by a power transfer assembly arranged to convert linear motion of the piston to rotary motion of the output shaft. The piston has a first head moveable within a first chamber and a second head opposite the first head and moveable within a second chamber. The power transfer assembly has a lubrication system for lubricating moving components of the power transfer assembly. The lubrication system is sealed from the first chamber and the second chamber to prevent the passage of fluid from the lubrication system into the first chamber and the second chamber.

Embodiments of outboard motors and related systems and components thereof, as well as arrangements of marine vessels implementing same, as well as related methods of operation, use, assembly, and manufacture, and related improvements, are disclosed herein. In at least some embodiments, the outboard motor includes a cowling system in which at least one divider portion separates an interior region into first and second portion, with the transmission and engine respectively being situated in the first and second portions, respectively. Additionally, in at least some embodiments, the outboard motor includes a water pump system in which a water pump is integrated with the transmission. Further, in at least some embodiments, the outboard motor includes a fuel vaporization suppression feature, or an oil tank feature that allows for desirable oil drainage from the engine of the outboard motor particularly when the outboard motor is in particular (e.g., storage) positions.

An exhaust manifold is for an internal combustion engine on an outboard marine engine that is configured to power a propulsor to provide a thrust in a longitudinal direction. The exhaust manifold comprises an exhaust runner that transversely and longitudinally rearwardly conveys the exhaust gas from the internal combustion engine, an exhaust log that vertically upwardly conveys the exhaust gas from the exhaust runner, and an exhaust elbow that conveys the exhaust gas from the exhaust log vertically upwardly, longitudinally forwardly, and then vertically downwardly.

The invention relates to a turbomachine of an aircraft comprising an outer casing (2) delimiting with an inner hub (3), a flow path (1) of a gas stream in which is disposed a low-pressure turbine configured to rotationally drive a low-pressure shaft; said turbomachine comprising, in the direction of flow of the gas stream, a first propeller (31); and a second propeller (32) downstream of the first propeller, the first propeller (31) being rotationally driven by said low-pressure shaft and the second propeller being rotationally driven by an electric motor (70), the second propeller (32) being further disposed at a distance between 1.5 and 4 cord lengths (LC1) from the first propeller (31) defined between the respective axes of shimming (A31, A32) of each of the first and second propellers.

The invention relates to a turbomachine of an aircraft comprising an outer casing (2) delimiting with an inner hub (3), a flow path (1) of a gas stream in which is disposed a low-pressure turbine configured to rotationally drive a low-pressure shaft; said turbomachine comprising, in the direction of flow of the gas stream, a first propeller (31); and a second propeller (32) downstream of the first propeller, the first propeller (31) being rotationally driven by said low-pressure shaft and the second propeller being rotationally driven by an electric motor (70), the second propeller (32) being further disposed at a distance between 1.5 and 4 cord lengths (LC1) from the first propeller (31) defined between the respective axes of shimming (A31, A32) of each of the first and second propellers.

A piston for an internal combustion engine is provided. The piston includes a piston body including an upper combustion surface, an annular side wall with a ring belt region, and a cooling gallery located within the piston body having a fluid inlet. A piston ring is located in a ring groove around the ring belt region and an alignment pin is secured in a hole in the piston side wall to restrict circumferential displacement of the piston ring. The piston body further includes a boss within the cooling gallery into which the hole and the alignment pin extend. The boss projects into the cooling gallery opposite the fluid inlet and is shaped to provide a flow splitter surface configured to divide cooling fluid flowing through the fluid inlet during use into first and second fluid flows and to direct the first and second fluid flows in opposite directions around the cooling gallery.

An outboard motor stabilizer of unitary construction has a cylindrical body and an axially oriented cylindrical orifice with an opening at the bottom end of the body. The orifice has a diameter sized to fit onto a tilt rod of an outboard motor and is of a length that is longer than the tilt rod of the outboard motor.

A low emission submersible engine is part of a multipurpose aquatic device, such as an aquatic craft or an electrical generator. A propulsion system having a propeller is coupled to the submersible engine to produce a swimmer propulsion machine and a generator is attached to the engine to produce an electrical generator. The submersible engine receives air from a snorkel that extends up above a water line. The aquatic device has a fuel reservoir which may receive liquid fuel or may receive a fuel cylinder. Floatation chambers keep the aquatic device afloat with the engine submerged. The exhaust assembly and exhaust ports from the engine may also be submerged and the exhaust ports may provide additional thrust. A propulsion system housing integrates the drive shaft and propeller, clutch coupler, exhaust conduits and water flow conduits and is detachably attachable to the engine.

A low emission submersible engine is part of a multipurpose aquatic device, such as an aquatic craft or an electrical generator. A propulsion system having a propeller is coupled to the submersible engine to produce a swimmer propulsion machine and a generator is attached to the engine to produce an electrical generator. The submersible engine receives air from a snorkel that extends up above a water line. The aquatic device has a fuel reservoir which may receive liquid fuel or may receive a fuel cylinder. Floatation chambers keep the aquatic device afloat with the engine submerged. The exhaust assembly and exhaust ports from the engine may also be submerged and the exhaust ports may provide additional thrust. A propulsion system housing integrates the drive shaft and propeller, clutch coupler, exhaust conduits and water flow conduits and is detachably attachable to the engine.