A torque fluctuation absorber includes a first outer helical spline, an intermediate member, an outer member, a first spring, and a second spring. The first outer helical spline is rotatable integrally with a torque transmission shaft. The intermediate member is able to move in a first axial direction and in a second axial direction. The intermediate member is linked with the torque transmission shaft through a first helical spline coupling including the first outer helical spline. Axial movement of the outer member with respect to the torque transmission shaft is regulated. The outer member is linked with the intermediate member through a second helical spline coupling. The first spring biases the intermediate member in the first axial direction. The second spring biases the intermediate member in the second axial direction.

A torque fluctuation absorber includes a first outer helical spline, an intermediate member, an outer member, a first spring, and a second spring. The first outer helical spline is rotatable integrally with a torque transmission shaft. The intermediate member is able to move in a first axial direction and in a second axial direction. The intermediate member is linked with the torque transmission shaft through a first helical spline coupling including the first outer helical spline. Axial movement of the outer member with respect to the torque transmission shaft is regulated. The outer member is linked with the intermediate member through a second helical spline coupling. The first spring biases the intermediate member in the first axial direction. The second spring biases the intermediate member in the second axial direction.

An outboard motor including an internal combustion engine for propelling a ship is equipped with an air-guiding system using a covering hood surrounding surfaces of the internal combustion engine and auxiliary units. The covering hood is provided with airflow inlet and outlet openings in its interior, and a fan driven by the internal combustion engine influences airflows in the covering hood. An air-guiding system includes channeling devices for partial air flows. First partial air flows are fed as intake air to an engine intake system, and second partial air flows act, with the aid of the fan, on surfaces of the internal combustion engine and the auxiliary units heated by operation of the internal combustion engine. The heated airflows are conveyed by the fan and a third channeling device as exhaust air via an outlet opening in the covering hood outside of the covering hood or into the atmosphere.

An outboard motor including an internal combustion engine for propelling a ship is equipped with an air-guiding system using a covering hood surrounding surfaces of the internal combustion engine and auxiliary units. The covering hood is provided with airflow inlet and outlet openings in its interior, and a fan driven by the internal combustion engine influences airflows in the covering hood. An air-guiding system includes channeling devices for partial air flows. First partial air flows are fed as intake air to an engine intake system, and second partial air flows act, with the aid of the fan, on surfaces of the internal combustion engine and the auxiliary units heated by operation of the internal combustion engine. The heated airflows are conveyed by the fan and a third channeling device as exhaust air via an outlet opening in the covering hood outside of the covering hood or into the atmosphere.

A fan is suitable for an air-guiding system of an outboard motor including an internal combustion engine and a covering hood bounding an engine interior space. The engine drives the fan, which is connected to an upright shaft journal projecting beyond an upper side of a housing of the engine. The covering hood has air flow openings, and the fan influences the air flows in the covering hood interior space. A flywheel, fixedly attached to the upright shaft journal, carries a fan wheel of the fan. The fan wheel is set in place from above, and the flywheel carries the fan wheel for conjoint rotation. Airflows enter the interior space via an inlet opening and a first conducting device, and the airflows, under the action of the fan, act upon at least parts of surfaces of the internal combustion engine and the auxiliary units to cool the internal combustion engine.

A fan is suitable for an air-guiding system of an outboard motor including an internal combustion engine and a covering hood bounding an engine interior space. The engine drives the fan, which is connected to an upright shaft journal projecting beyond an upper side of a housing of the engine. The covering hood has air flow openings, and the fan influences the air flows in the covering hood interior space. A flywheel, fixedly attached to the upright shaft journal, carries a fan wheel of the fan. The fan wheel is set in place from above, and the flywheel carries the fan wheel for conjoint rotation. Airflows enter the interior space via an inlet opening and a first conducting device, and the airflows, under the action of the fan, act upon at least parts of surfaces of the internal combustion engine and the auxiliary units to cool the internal combustion engine.

A marine vessel engine in which moving parts found in conventional marine engines are eliminated, wherein such engine is used for the propulsion of marine vessels. In the marine vessel engine, no lubrication or cooling is required, and a column of water replaces the conventional piston in a cylinder of the engine, wherein such water column partially fills such cylinder. The marine vessel engine comprises a cylinder, a bent tube with a plurality of openings and two ends, a flapping member, at least one solenoid valve, and an exhaust. In operation of the marine vessel engine, a column of water fills the cylinder through the bent tube openings, and is purged outside from the cylinder through the flapping member. The at least one solenoid valve controls the flow of a power source into the cylinder.

A vessel power supply system for a vessel including a propulsion device that includes an engine and a generator driven by the engine to generate electricity, includes a first battery that supplies power to the propulsion device, a second battery that supplies power to accessories of the vessel, a first open circuit voltage sensor that detects an open circuit voltage of the first battery, a second open circuit voltage sensor that detects an open circuit voltage of the second battery, and a switch that is turned on/off to open and close a current path between the first battery and the second battery.

A vessel power supply system for a vessel including a propulsion device that includes an engine and a generator driven by the engine to generate electricity, includes a first battery that supplies power to the propulsion device, a second battery that supplies power to accessories of the vessel, a first open circuit voltage sensor that detects an open circuit voltage of the first battery, a second open circuit voltage sensor that detects an open circuit voltage of the second battery, and a switch that is turned on/off to open and close a current path between the first battery and the second battery.

A method of controlling propulsion for automated launch control includes receiving a user-selected command associated with wake surfing, accessing a predetermined RPM limit associated with the user-selected command, and automatically increasing rotational speed of a powerhead to accelerate the marine vessel to a vessel speed setpoint such that the rotational speed does not exceed the predetermined RPM limit. Once the marine vessel is traveling at the vessel speed setpoint, a cruising RPM value associated with the vessel speed setpoint is identified. A difference between the predetermined RPM limit and the cruising RPM value is determined, and then the predetermined RPM limit is adjusted to an adapted RPM limit based on the difference. The adapted RPM limit is then stored for use during a subsequent launch.