An engine for an outboard motor is provided with an engine body, an intake system configured to supply combustion air to the engine body, an exhaust passage formed by connecting the engine body and the middle and lower units thereunder, a catalyst provided in the exhaust passage, and an air pump configured to supply secondary air to the upstream side of the catalyst. The air pump is driven by an electric motor.

A boat propulsion device includes an engine, a fuel tank, a fuel path, a fuel pump, and a controller. The engine includes a fuel injection device. The fuel tank includes a fuel storage region configured to store fuel. The fuel path is connected to the fuel injection device and the fuel tank. The fuel pump is disposed in the fuel path and is configured to discharge the fuel stored in the fuel storage region to the fuel injection device. The controller is configured and/or programmed to control a load on the fuel pump. The controller is configured and/or programmed to include an empty-fuel condition detector configured to detect that the fuel stored in the fuel storage region has become a predetermined remaining amount or less based on a variation in the load on the fuel pump.

An outboard motor includes a drive source, a motor controller, a coolant tube, a pump, and an air vent. The drive source includes an electric motor. The motor controller is higher than the electric motor and controls the electric motor. The coolant tube includes at least a portion of a coolant flow path through which the coolant that cools the electric motor and the motor controller circulates. The pump is connected to the coolant tube to pump the coolant. The air vent is located at an uppermost portion of the coolant flow path. The coolant pumped by the pump through the coolant flow path flows in an order of the motor controller, the air vent, and the electric motor.

An outboard motor includes an outboard motor body, a steering shaft, a steering cylinder including a piston rod extending in a right-left direction of the outboard motor body, a piston fixed to the piston rod, and a cylinder body including an oil chamber and the piston therein, and an oil passage inside the piston rod and connected to the oil chamber. The steering cylinder is operable to rotate the steering shaft and the outboard motor body in the right-left direction by adjusting an amount of oil in the oil chamber and moving the cylinder body in the right-left direction.

An outboard motor includes a first pipe made of metal to allow high-pressure hydrogen to be supplied therethrough to a first fuel injector, a second pipe made of metal to allow the high-pressure hydrogen to be supplied therethrough to a second fuel injector, and a flexible pipe made of bendable metal to connect the first pipe to the second pipe so as to allow the high-pressure hydrogen to flow therethrough to both the first pipe and the second pipe.

The invention provides a vapor separator easily assembled with a fuel pump while suppressing cost increases due to increase in number of parts, and a method for producing the vapor separator. A vapor separator installed in a fuel supply system is provided with: a tank for storing liquid fuel; and a fuel pump disposed in the tank. The tank includes: upper member assembled with an upper portion of the fuel pump; and lower member located below the upper member, connected to upper member, and having a holding part for holding a lower portion of the fuel pump. Lower member of tank includes a guide part located between side wall of lower member and the holding part in plan view, the guide part serving to guide lower portion of the fuel pump toward the holding part when upper member with upper portion of fuel pump attached is assembled to lower member.

A thermal management system for a marine vessel. The thermal management system includes an open loop circuit and a pump that pumps water from a body of water, through the open loop circuit, and back to the body of water. The thermal management system further includes a closed loop circuit and a pump that pumps a heat transfer fluid through the closed loop circuit. A heat exchanger is configured to exchange heat between the water and the heat transfer fluid. The thermal management system includes multiple components each cooled or heated by the heat transfer fluid. A valve has valve positions configured to vary a sequence that the heat transfer fluid is conveyed to the components so as to vary how the components share the heating and cooling from the heat transfer fluid and from the water from the body of water via the heat transfer fluid.

An outboard motor includes an engine and a plurality of fuel supply mechanisms each including a suction pump to suck in liquid fuel stored in a fuel tank in a hull, a vapor separator tank to store liquid fuel sucked in by the suction pump and separate the liquid fuel and vapor, and a supply pump to supply the liquid fuel stored in the vapor separator tank to the engine.

A thermal management system for a marine vessel. The thermal management system includes an open loop circuit and a pump that pumps water from the body of water, through the open loop circuit, and back to the body of water. The thermal management system further includes a closed loop circuit including a first path and a second path parallel to each other. Another pump pumps a heat transfer fluid through the closed loop circuit. One heat exchanger exchanges heat between the water and the heat transfer fluid. A second heat exchanger exchanges heat with the heat transfer fluid. A component is cooled or heated by the heat transfer fluid. One or more valves select between conveying the heat transfer fluid via the second path to the second heat exchanger and via the first path to bypass the second heat exchanger to vary the cooling or heating of the component.

An outboard motor includes an engine, a fuel pump to draw fuel into an outboard motor body from a fuel tank installed on a hull, a temporary storage tank to temporarily store the fuel drawn into the outboard motor body by the fuel pump, a fuel injector to inject the fuel stored in the temporary storage tank into the engine, a temperature sensor on the temporary storage tank to detect a temperature of the fuel stored in the temporary storage tank, and a controller configured or programmed to perform a control to limit an engine speed to no more than a predetermined upper limit rotation speed based on a detection result of the temperature sensor while the engine is running.