A marine engine has a crankshaft that rotates about a crankshaft axis; a crankcase supporting the crankshaft, the crankcase being made primarily of a first material; and a cover on the crankcase. The cover includes a heat exchanger having an inner plate facing an interior of the crankcase, and the inner plate is located such that rotation of the crankshaft causes lubricant in the crankcase to impinge upon the inner plate. The cover also includes a frame holding the heat exchanger and isolating the heat exchanger from direct contact with the crankcase. At least a portion of the frame is made of a second material that is more compliant than the first material.

A propulsion unit (1) for a marine vessel, comprising a shell structure (2), a shaft (4) rotatably coupled to a propulsion motor (3) inside the shell structure (2), and a propeller (5) coupled to the shaft (4) outside the shell structure (2). A shaft seal arrangement (6) is provided to engage the shaft (4), such that at least a first seal chamber (6a) is delimited between adjacent seal lips (6′) and the shaft (4). A first lubrication arrangement is provided for circulating a first lubricant through the first seal chamber (6a). The first lubrication arrangement (7) further comprises a first lubricant heat exchanger (7e) arranged at least partly outside of the shell structure (2) for conducting the first lubricant therethrough and for transferring heat from the first lubricant to an outside environment of the shell structure (2). A propulsion unit for a marine vessel, including a shell structure, a shaft rotatably coupled to a propulsion motor inside the shell structure, and a propeller coupled to the shaft outside the shell structure. A shaft seal arrangement is provided to engage the shaft, such that at least a first seal chamber is delimited between adjacent seal lips and the shaft. A first lubrication arrangement is provided for circulating a first lubricant through the first seal chamber. The first lubrication arrangement further includes a first lubricant heat exchanger arranged at least partly outside of the shell structure for conducting the first lubricant therethrough and for transferring heat from the first lubricant to an outside environment of the shell structure.

A marine propulsion unit includes a stern drive mounted to a transom. The stern drive comprises an upper unit enclosed in a stern drive housing and a lower unit enclosed in a gearbox housing; wherein the gearbox housing contains a gearbox arranged to drive at least one propeller. The propulsion unit further comprises at least two electric motors arranged in the stern drive housing, which electric motors are mounted with vertical output shafts; a planetary gear set arranged between the at least two electric motors and the gearbox, and a vertical shaft that is attached to a ring gear of the planetary gear set at its upper end and is connected to the gearbox at its lower end; wherein the output shaft of each electric motor is connected to a planetary gear arranged in the planetary gear set to drive the ring gear and the vertical shaft connected to the gearbox.

A watercraft (10) including a board (12), a mast (16) extending below the board, (12) the mast (16) carrying a foil (20) and a propeller (30) that is driven by a motor (32), the motor (32) being carried in a tube (18) connected to or extending from the mast (16), wherein a motor controller (34) is also positioned within the tube (18). In this manner, heat generated by the motor controller during use is dissipated into the water through which the watercraft is travelling. The watercraft (10) may also have a receptacle for holding lubricant, the receptacle being located above the motor, wherein the mast has a conduit that provides fluid communication between the receptacle and the lubricant lubricating the motor and/or driveshaft such that lubricant in the receptacle provides a hydrostatic head of pressure to prevent or minimise water ingress around a propeller seal or a driveshaft seal located adjacent a region where the driveshaft exits into the water.

The present invention discloses a method and device for controlling energy-saving sailing of a ship. The method comprises the steps of changing the operating parameters of the ship correspondingly when the resistance of the ship changes during routine sailing, controlling the current opening degree of a throttle to increase the instantaneous oil supply amount of a main engine of the ship if the resistance of the ship becomes smaller, and controlling the current opening degree of the throttle to reduce the instantaneous oil supply amount of the main engine of the ship if the resistance of the ship becomes larger. Compared with the prior art, the method and device have the advantages that energy waste is reduced greatly and the sailing cost is reduced.

A cycloidal marine propulsion unit, including a hollow rotary casing having a central axis and defining a central inner space with an opening at an axial end thereof. A mounting body rotatably supports the rotary casing on a hull of a marine vessel. A rotating arrangement is provided for rotating said hollow rotary casing, while a plurality of blades extend axially from the rotary casing away from the hull. Each blade is mounted for pivotal movement with respect to the rotary casing, about respective blade axes. The rotating arrangement is configured to rotate the rotary casing by a circumference thereof. A blade shaft portion of each blade is at least partly received within the central inner space so as to attach said blade to the rotary casing.

A fuel supply control system and control method are disclosed. In a fuel supply control system of a high-pressure gas injection engine provided in a ship or an offshore structure, the fuel supply control system of the present invention includes: a gas supply mode for supplying gas to the high-pressure gas injection engine through a gas supplying part for receiving LNG from a storage tank so as to compress and vaporize the LNG; and an oil supply mode for supplying oil as fuel to the high-pressure gas injection engine, wherein the mode is switched into the oil supply mode during an emergency including a device malfunction in the gas supply mode such that the oil supply mode can be configured as a redundancy of the gas supply mode.

A method of and an arrangement for improving the lubrication system of a propulsion device of a marine vessel are specifically applicable in removing water from the lubrication oil of various types of thrusters. An inert gas is arranged from an inert gas source to flow through a gas cavity in the lubrication system for flushing moist gas from the cavity.

A hose fitting is provided to fluidly couple a hose to a component of a boat engine. The hose fitting includes a lead in portion having a substantially smooth exterior surface, a barbed portion with multiple barbs configured to sealingly engage with an inner liner of the hose, a grip portion with multiple substantially flat grip faces; and a terminating portion configured to couple to the component of the boat engine. The lead in portion, the barbed portion, the grip portion, and the terminating portion collectively define a central flow passage extending through the hose fitting.

An engine oil receiving structure comprises a vertically disposed crank shaft, a laterally movable piston, a connecting rod connecting the crank shaft and the piston, a cylinder barrel housing the crank shaft and the piston, a crank case containing the crank shaft together with the cylinder barrel, a cylinder head forming a combustion chamber, the combustion chamber connecting to a piston movable part end face of the cylinder barrel, an oil filter filtering engine lubricant, and an oil case storing oil flowing out when the oil filter is removed from a mounted position, and the oil case is fixed to an engine under the oil filter, and comprises a discharge path to discharge the stored oil.