A V-type engine in which exhaust pipe arrangement is easily performed and purification of exhaust gas can be performed by a single catalyst. Cylinders where pistons operate are arranged in a V-shape, a crankshaft driven by the driving of the pistons is disposed vertically, exhaust pipes communicating with exhaust openings in the respective banks of a cylinder head are included, rear exhaust pipes in the respective banks are merged outside on a side of the crankshaft, and a catalyst holder that holds a catalyst is provided in a merge portion of the rear exhaust pipes. Since the rear exhaust pipes in the respective banks are merged and the catalyst holder is provided in this merge portion, exhaust gas from each bank can be purified by the single catalyst, so that the number of catalysts installed is reduced to thus be able to reduce manufacturing cost.

An outboard motor includes an engine, a cooling water passage, a pump that is driven in conjunction with the engine, an inlet water passage that branches from the cooling water passage, an oil cooler, an outlet water passage, a first thermostat located in the cooling water passage, and a second thermostat. The pump takes outside water into the cooling water passage. The oil cooler includes a water-storing space into which water in the inlet water passage is taken. The outlet water passage is connected to an outlet of the oil cooler. The first thermostat increases and decreases the flow rate of water flowing through the engine. The second thermostat is located at the outlet or at the outlet water passage, and increases and decreases the flow rate of water flowing through the outlet water passage.

An outboard motor includes an engine, an engine cover with which the engine is covered, an intake pipe disposed between an outer surface of the engine and an inner surface of the engine cover, and a battery. The engine includes a piston that reciprocates rectilinearly and a crankshaft that rotates around a crankshaft axis extending in an up-down direction. The intake pipe is connected to a first outer surface of the engine along the crankshaft axis, and supplies air to the engine. The battery is disposed between a second outer surface of the engine, which is different than the first outer surface, and the inner surface of the engine cover.

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.

An outboard motor includes an engine, a cooling water passage, a pump that is driven in conjunction with the engine, an inlet water passage that branches from the cooling water passage, an oil cooler, an outlet water passage, a first thermostat located in the cooling water passage, and a second thermostat. The pump takes outside water into the cooling water passage. The oil cooler includes a water-storing space into which water in the inlet water passage is taken. The outlet water passage is connected to an outlet of the oil cooler. The first thermostat increases and decreases the flow rate of water flowing through the engine. The second thermostat is located at the outlet or at the outlet water passage, and increases and decreases the flow rate of water flowing through the outlet water passage.

A thermostat includes an annular flange extending in radial directions and surrounded by a cylindrical large-diameter portion of a housing inner surface, and a frame extending in axial directions from the flange. The thermostat further includes a sealing member that hermetically seals the gap between the flange and the inner surface. The sealing member includes an annular outer peripheral portion sandwiched in the axial directions by the inner surface and a thermostat cover inside the large-diameter portion, and a plurality of protruding portions extending outward in the radial directions from the outer peripheral portion toward the large-diameter portion. The thermostat is disposed inside a housing that defines a portion of a cooling water passage, and opens and closes the cooling water passage according to the temperature of cooling water inside the cooling water passage.

An outboard motor includes an engine, an engine cover with which the engine is covered, an intake pipe disposed between an outer surface of the engine and an inner surface of the engine cover, and a battery. The engine includes a piston that reciprocates rectilinearly and a crankshaft that rotates around a crankshaft axis extending in an up-down direction. The intake pipe is connected to a first outer surface of the engine along the crankshaft axis, and supplies air to the engine. The battery is disposed between a second outer surface of the engine, which is different than the first outer surface, and the inner surface of the engine cover.

A V-type engine in which exhaust pipe arrangement is easily performed and purification of exhaust gas can be performed by a single catalyst. Cylinders where pistons operate are arranged in a V-shape, a crankshaft driven by the driving of the pistons is disposed vertically, exhaust pipes communicating with exhaust openings in the respective banks of a cylinder head are included, rear exhaust pipes in the respective banks are merged outside on a side of the crankshaft, and a catalyst holder that holds a catalyst is provided in a merge portion of the rear exhaust pipes. Since the rear exhaust pipes in the respective banks are merged and the catalyst holder is provided in this merge portion, exhaust gas from each bank can be purified by the single catalyst, so that the number of catalysts installed is reduced to thus be able to reduce manufacturing cost.

An outboard motor includes a bracket, an upper case, a lower case, a drive shaft, a propeller shaft, a cooling water passage, a water pump, and an electric motor. The outboard motor is attached to a watercraft via the bracket. The upper case is below the engine. The lower case is below the upper case. The drive shaft is in the upper case and the lower case. The propeller shaft is connected to the drive shaft. The propeller shaft is in the lower case. The cooling water passage is connected to the engine. The cooling water passage is in the upper case and the lower case. The water pump is below a lower end of the bracket to deliver cooling water to the engine through the cooling water passage. The electric motor is operable to drive the water pump.

An outboard motor includes an engine, a flywheel magnet generator, a fan, and a cover member. The engine includes a crankshaft extending in a vertical direction. The flywheel magnet generator includes a flywheel rotor, a core, and a coil. The flywheel rotor is attached to an end of the crankshaft. The core and the coil are disposed between the flywheel rotor and the engine. The fan is attached onto the flywheel rotor. The cover member is disposed above the fan. The cover member includes a first suction port that sucks in air from above the cover member. The flywheel rotor includes a second suction port that sucks in air from below the flywheel rotor. The fan includes a first ventilation path and a second ventilation path. The first ventilation path radially outwardly releases the air sucked in through the first suction port, whereas the second ventilation path radially outwardly releases the air sucked in through the second suction port.