An outboard motor having an internal combustion engine that causes rotation of a driveshaft, a planetary transmission that operatively connects the driveshaft to a transmission output shaft, a band brake configured to shift the planetary transmission amongst a forward gear, neutral gear and reverse gear, a hydraulic actuator is configured to actuate the band brake, and a cooling water circuit that extends adjacent to the hydraulic actuator so that the hydraulic actuator exchanges heat with cooling water in the cooling water circuit.

Upper anti-vibration mounts have axial lines arranged in parallel to a longitudinal center line extending in a longitudinal direction of the outboard motor body. Lower anti-vibration mounts have axial lines concentrated on one point on the longitudinal center line extending in a longitudinal direction of the outboard motor body. Meanwhile, the axial lines are inclined at the identical angle symmetrically with respect to the longitudinal center line, so that they intersect in a V-shape in front of the support shaft as seen in a plan view of the outboard motor body.

An outboard motor includes a catalyst housing passage disposed inside the V-shaped line, a cooling water passage including at least a portion disposed at a periphery of a catalyst and that guides cooling water that cools an exhaust passage and a vent hole disposed higher than the catalyst and that connects the interior of the cooling water passage to the exterior of the cooling water passage.

An outboard motor includes a catalyst housing passage disposed inside the V-shaped line, a cooling water passage including at least a portion disposed at a periphery of a catalyst and that guides cooling water that cools an exhaust passage and a vent hole disposed higher than the catalyst and that connects the interior of the cooling water passage to the exterior of the cooling water passage.

A marine propulsion unit is described. The marine propulsion unit allows for shallow, obstructed, or otherwise impeded operation of a vessel through a novel marine propulsion transfer unit that is, or can be, mechanically coupled to an outboard motor or other similar marine motor. A mount for raising and lowering the marine propulsion unit in a generally vertical direction allows for adjustment of operating depth of the marine propulsion unit to accommodate a wide range of operating conditions from shallow and obstructed water to traditional deep water operation.

An outboard motor includes a gear housing configured to rotatably house a propeller shaft that transmits a rotative power output from an engine to a propeller device. The gear housing includes a torpedo shape portion and a strut portion. The torpedo shape portion has a shape tapered toward a front side, and a shape biased upward toward the front side. The strut portion is disposed on an upper side of the torpedo shape portion. An outer peripheral surface of the torpedo shape portion is smoothly coupled to an outer peripheral surface of the strut portion via first to third curved surfaces. The first to third curved surfaces are each a curved surface inclined rearward and downward, a curved surface parallel to a front-rear direction, or a curved surface constituted of a part inclined rearward and downward and a part parallel to the front-rear direction.

An outboard motor includes a gear housing configured to rotatably house a propeller shaft that transmits a rotative power output from an engine to a propeller device. The gear housing includes a torpedo shape portion and a strut portion. The torpedo shape portion has a shape tapered toward a front side, and a shape biased upward toward the front side. The strut portion is disposed on an upper side of the torpedo shape portion. An outer peripheral surface of the torpedo shape portion is smoothly coupled to an outer peripheral surface of the strut portion via first to third curved surfaces. The first to third curved surfaces are each a curved surface inclined rearward and downward, a curved surface parallel to a front-rear direction, or a curved surface constituted of a part inclined rearward and downward and a part parallel to the front-rear direction.

An outboard motor includes an engine, a supercharger that compresses air to be supplied to an air intake of the engine, and a cooler that cools the air compressed by the supercharger. The compressed air is cooled by spraying water obtained by condensing water vapor produced by combustion in the engine to the cooler.

An outboard motor includes an engine, a supercharger that compresses air to be supplied to an air intake of the engine, and a cooler that cools the air compressed by the supercharger. The compressed air is cooled by spraying water obtained by condensing water vapor produced by combustion in the engine to the cooler.

An outboard motor for a marine vessel application, and related methods of making and operating same, are disclosed herein. In at least one embodiment, the outboard motor includes a horizontal-crankshaft engine in an upper portion of the outboard motor, positioned substantially positioned above a trimming axis of the outboard motor. In at least another embodiment, first, second and third transmission devices are employed to transmit rotational power from the engine to one or more propellers at a lower portion of the outboard motor. In at least a further embodiment, the outboard motor is made to include a rigid interior assembly formed by the engine, multiple transmission devices, and a further structural component. In further embodiments, the outboard motor includes numerous cooling, exhaust, and/or oil system components, as well as other transmission features.