Abstract: An immobilizer receiver for an outboard motor includes a control unit that is housed in a liquid-tight case and arranged to receive an authentication code, an antenna wire arranged to receive the authentication code, and an answer-back buzzer arranged to provide an indication that the authentication code has been received, which are housed in a recessed section of a housing. A distance from an opening surface to a bottom surface of the recessed section of the housing is arranged such that the antenna wire can receive the authentication code even in a case that a hull is made of metal. Then, the opening surface of the housing is preferably mounted on a vertical or approximately vertical surface of the hull. Therefore, it is possible to secure a receiving function of the antenna wire that is housed on the bottom surface of the recessed section. In addition, the answer-back buzzer is protected against coming in contact with water.

Abstract: A control device for a marine propulsion system includes a base and at least two levers. Each one of the levers is supported by the base at a first end for pivotal movement about a common pivot axis and extending generally normal to the pivot axis to have a second end. The second end has a grip. The grip of one of the levers extends toward the second end of the other one of the levers. The respective grips are nested with each other when the levers extend generally parallel to each other.

Abstract: An immobilizer receiver for an outboard motor includes a control unit that is housed in a liquid-tight case and arranged to receive an authentication code, an antenna wire arranged to receive the authentication code, and an answer-back buzzer arranged to provide an indication that the authentication code has been received, which are housed in a recessed section of a housing. A distance from an opening surface to a bottom surface of the recessed section of the housing is arranged such that the antenna wire can receive the authentication code even in a case that a hull is made of metal. Then, the opening surface of the housing is preferably mounted on a vertical or approximately vertical surface of the hull. Therefore, it is possible to secure a receiving function of the antenna wire that is housed on the bottom surface of the recessed section. In addition, the answer-back buzzer is protected against coming in contact with water.

Abstract: A remote control device for controlling a propulsion unit of a boat is provided. The remote control device comprises a main body having a shift lever. A housing board is coupled to the main body of the remote control device and extends in a downward direction. The housing board houses a remote control engine control unit that provides an operation output signal to the propulsion unit based on an operation input signal received from the shift lever. In one embodiment, an operator can access the remote control engine control unit from either a starboard side or a port side of the boat. The remote control device can include an additional housing board that is capable of being attached to and detached from the housing board that is coupled to the main body.

Abstract: A remote control unit can be used for a boat having a plurality of propulsion units to perform output adjustment and tilt/trim angle adjustment of the propulsion units. Operating levers can be capable of forward and backward rotational movement to effect shift operation and throttle operation of the propulsion units and can be respectively provided upright on a left side surface and right side surface of a body. A plurality of tilt/trim angle adjustment switches can correspond to respective propulsion units and can be provided at positions where they can be operated with fingertips of a hand resting on a palm portion of a top surface of the body with the fingertips pointing generally forward. The palm portion of the top surface can be free of switches.

Abstract: A remote control device for controlling a propulsion unit of a boat is provided. The remote control device comprises a main body having a shift lever. A housing board is coupled to the main body of the remote control device and extends in a downward direction. The housing board houses a remote control engine control unit that provides an operation output signal to the propulsion unit based on an operation input signal received from the shift lever. In one embodiment, an operator can access the remote control engine control unit from either a starboard side or a port side of the boat. The remote control device can include an additional housing board that is capable of being attached to and detached from the housing board that is coupled to the main body.

Abstract: A remote control unit can be used for a boat having a plurality of propulsion units to perform output adjustment and tilt/trim angle adjustment of the propulsion units. Operating levers can be capable of forward and backward rotational movement to effect shift operation and throttle operation of the propulsion units and can be respectively provided upright on a left side surface and right side surface of a body. A plurality of tilt/trim angle adjustment switches can correspond to respective propulsion units and can be provided at positions where they can be operated with fingertips of a hand resting on a palm portion of a top surface of the body with the fingertips pointing generally forward. The palm portion of the top surface can be free of switches.

Abstract: A control device for a marine propulsion system includes a base and at least two levers. Each one of the levers is supported by the base at a first end for pivotal movement about a common pivot axis and extending generally normal to the pivot axis to have a second end. The second end has a grip. The grip of one of the levers extends toward the second end of the other one of the levers. The respective grips are nested with each other when the levers extend generally parallel to each other.

Abstract: An outboard motor and improved torsional vibration damper adapted to be supported on the lower end of the output shaft of the engine of the outboard motor. The torsional vibration damper is formed with an oil receiving groove in which oil and fuel which may drain from the engine can collect without affecting the elastomeric sleeve. A drain hole permits the oil to be relieved from the oil collecting groove and this drain hole is threaded so as to receive a puller for pulling the torsional damper from the engine output shaft.

Abstract: A latching mechanism for connecting the top portion and tray of a cowling which surrounds an internal combustion engine of an outboard motor. In the preferred embodiment, a pair of keepers, one secured to the front side of the top portion of the cowling and the other secured to the rear side of the top portion, engage with a connecting mechanism, secured on the front and rear sides of the tray of the cowling, to connect the top portion and tray of the cowling with each other. An operating lever supported for rotation about a vertical shaft is operatively connected to the connecting mechanism such that rotation of the lever releases the connecting mechanism from the keepers so that the top portion of the cowling can be detached from the tray.

Abstract: An outboard motor having an improved, compact induction system for a V-type engine. The induction system includes angularly related intake passages that are disposed at an angle that is less than the angle between the cylinder banks. Reed valves are interposed between the intake passages and the crankcase chamber. These reed valves extend perpendicularly to extensions of the cylinder bore axes. An improved balancing arrangement is also incorporated that comprises plenum chambers that surround the pairs of intake passages and the intake passages each communicate with the respective plenum chambers through relatively small openings.

Abstract: Two embodiments of protective cowlings for the power head of an outboard motor that form both forwardly and rearwardly facing air inlet openings so as to insure adequate air induction to the engine. The forwardly facing air inlet opening is located so as to avoid water being able to enter into the interior of the protective cowling and into the engine induction system.

Abstract: An improved lubricating system for the internal combustion engine of an outboard motor. A lubricant sump is positioned beneath the engine and oil is returned to the sump through a drain opening in a spacer plate that separates the engine from the drive shaft housing. The oil sump and drain opening are configured so that oil will not return from the sump through the drain opening to the engine when the outboard motor is laid on its side edge.

Abstract: An improved thrust taking arrangement for an outboard drive wherein anti-friction members are provided for transferring the thrust between the trim adjusting thrust member and the outboard drive. The anti-friction members comprise rollers carried in a downwardly facing opening of the outboard drive. In some embodiments, the rollers are balls and in other embodiments they are cylindrical elements that rotate about an axis parallel to the trim pivot axis of the outboard drive. In some embodiments, the roller members contact a concavely curved surface of the thrust member and the radii of curvature are different so as to minimize relative movement.

Abstract: An outboard motor cowling arrangement wherein the cowling includes a tray that is affixed directly to the drive shaft housing independently of the other cowling portions.

Abstract: A steering device for an outboard motor that releasably restrains the motor in a predetermined position and which can be automatically released upon the exertion of more than a predetermined force to the motor to steer it in the event of an emergency. The releasable restraining device is also automatically engageable upon return of the motor to its first position and can be manually released.

Abstract: Two embodiments of water-cooled, four-cycle internal combustion engines used for outboard motors. In each embodiment, an arrangement is provided that offers a compact nature and which uses the coolant delivered to the engine for cooling the oil in the oil pan. In addition, an arrangement is provided whereby the exhaust pipe may pass through the oil pan and yet avoid significant heat transfer from the exhaust system to the lubricating system. In each embodiment of the invention, coolant is delivered to this clearance for further cooling the exhaust system. In one embodiment of the invention, an arrangement is provided for limiting the discharge of coolant from the clearance so as to maintain a level of coolant around the exhaust pipe.

Abstract: A water cooled, four-cycle internal combustion engine particularly adapted for use in an outboard motor. A supporting plate arrangement is used with the supporting plate extending across the driveshaft housing at its upper end. The engine is supported on the upper side of the supporting plate and an oil pan is supported on the underside of the supporting plate and depends into the driveshaft housing. The construction is such that the engine may be removed from the supporting plate without necessitating removal of the oil pan from the supporting plate so as to facilitate servicing. In addition, an oil drain is provided through the supporting plate at such a location so as to insure against leakage of the lubricant from the oil sump back into the engine regardless of whether the engine is in its normal running condition or its tilted up condition.