Abstract: A mounting assembly for a marine propulsion system includes a horizontal mounting plate, a pivot housing, and an adapter plate attached to one another through a plurality of vibration absorbing isolation points. The adapter plate is configured for attachment to an outboard powerhead, and the horizontal mounting plate is configured for horizontal attachment to a boat platform. The pivot housing is configured for attachment to a steering arm that extends through the horizontal mounting plate for rotating and pivoting an attached steering arm yoke and trunnion assembly and propeller drive unit. A contoured opening in the horizontal mounting plate facilitates drop down installation of a marine propulsion system.

Abstract: A steering arm yoke and trunnion assembly for a marine propulsion system includes a steering arm and a yoke including integral fluid paths for trim actuator fluids and for cooling water for an outboard powerhead mounted to a horizontal mounting plate within a platform extending from a boat hull. The steering arm and yoke include a drum extending through the horizontal mounting plate for rotating an attached propeller drive unit. The fluid paths extend through the drum, which is rotatably mounted to the horizontal mounting plate. The yoke includes pivot arms for attachment to a trunnion that includes actuator brackets for trim actuators fluidly connected to the actuator fluid paths of the drum.

Abstract: A marine propulsion system includes an outboard powerhead mounted to a horizontal mounting plate within a boat platform recess. A steering arm is attached to a yoke that extends through the transom plate for rotating an attached propeller drive unit. The yoke includes integral fluid paths for hydraulic cylinders coupled to the yoke to pivot the propeller drive unit, and for powerhead cooling water. A removable gearcase plate allows the outboard powerhead, the horizontal mounting plate, the steering arm and the yoke to be pre-assembled and dropped down through the boat platform recess.

Abstract: A two-stroke internal combustion engine comprising an engine block, a plurality of crankcases and including a mounting surface having therein a plurality of inlet openings each communicating with a respective one of the crankcases, a throttle housing defining a throttle passage and including a plenum mounting surface, a throttle valve in the throttle passage, and a plenum member which is separable from both the engine block and the throttle housing and which defines a plurality of intake passages each having an outlet end communicating with a respective one of the inlet openings and each having an inlet end communicating with the throttle passage such that the intake of the engine can be tuned solely by modifying the configuration of the plenum member.

Abstract: A marine propulsion device comprising a propulsion unit which is adapted to be mounted on a boat and which includes a propeller shaft and an internal combustion engine drivingly connected to the propeller shaft, the engine including engine block structure having a combustion chamber and defining an air intake passage communicable with the combustion chamber, a throttle plate movably supported by the engine block structure and located in the air intake passage, structure for moving the throttle plate in response to movement of an operator control member, and structure supported by the engine block structure for providing a signal indicating the position of the control member independent of the position of the throttle plate.

Abstract: An outboard motor comprising a propulsion unit adapted to be mounted on a boat for pivotal movement relative thereto about a generally horizontal axis, the propulsion unit including a propeller shaft, and an engine drivingly connected to the propeller shaft, and the outboard motor further comprising structure for pivoting the propulsion unit about the generally horizontal axis, the pivoting structure being adapted to be mounted outside the boat, and the pivoting structure comprising a housing having an interior and an exterior, an electric motor in the interior, and a first quick-disconnect connector portion which is electrically connected to the motor and which is accessible from the exterior of the housing for selective mating with another quick-disconnect connector portion.

Abstract: A shock absorber adapted for use with the swivel bracket assembly of an outboard motor or the like, is disclosed, which swivel bracket assembly permits rotation of the motor to clear an underwater object if and when a boat strikes such an object. The shock absorber has a two stage operation in that it permits a swivel bracket assembly to rotate and provides a counterforce that is initially lower, and after some degree of rotation, preferably sufficient to have the drive shaft housing clear the object, provides a higher counterforce to continued rotation.

Abstract: A tiller arm for a marine propulsion device, the tiller arm comprising a first end adapted to be connected to a propulsion unit, a second end spaced from the first end, a longitudinal axis, and a selectively actuable switch including annular selectively deformable structure surrounding the axis, deformation of the deformable structure resulting in actuation of the switch.

Abstract: A marine propulsion device comprising a transom bracket adapted to be mounted on a boat transom and including laterally spaced rearwardly extending port and starboard portions, and a swivel bracket including a first leg connected to the transom bracket for pivotal movement about a horizontal axis and a second leg extending generally perpendicularly to the first leg and including a transversely extending portion extending in closely adjacent relation to both of the rearwardly extending laterally spaced transom bracket portions and substantially bridging the space between the rearwardly projecting laterally spaced transom bracket portions.

Abstract: Disclosed herein is a marine propulsion device comprising a transom bracket adapted to be mounted on a boat transom and including a rearwardly and laterally open socket, a swivel bracket connected to the transom bracket for pivotal movement about a horizontal tilt axis, a trail arm pivotally mounted on the swivel bracket for movement between a retracted position adjacent the swivel bracket and an extended position projecting from the swivel bracket and including an outer end receivable in the socket in the transom bracket and having a laterally extending projection, a latch member pivotally mounted on the transom bracket for movement between a retracted position and a latching position, which latch member includes a hook located, when the latch member is in the latching position, for engagement with the projection to prevent withdrawal of the outer end of the trail arm from the socket, and which hook is located, when the latch member is in the retracted position, clear of interferring engagement with travel o

Abstract: A marine propulsion device comprising a lower unit, a propeller shaft rotatably supported by the lower unit and adapted to support a propeller, an engine supported by the lower unit and drivingly connected to the propeller, the engine including an engine block, and a throttle arm movably mounted on the engine block, a control cable operably connected to the throttle arm, a mechanism for removably securing the control cable to the engine block, and a cowl assembly surrounding the engine and including a pan-like lower cover member and a dome-shaped upper cover member, one of the cover members having therein an access opening affording access to the mechanism for securing the control cable to the engine block, and an access cover removably secured to the cover member in covering relation to the access opening.

Abstract: Disclosed herein is a marine propulsion device comprising a transom bracket adapted to be mounted on a boat transom and including an upper surface, a swivel bracket connected to the transom bracket for pivotal movement about a horizontal tilt axis, a holding member pivotally mounted on the swivel bracket for movement about a horizontal second axis between a park position, a low-tilt position, and a high-tilt position, which holding member includes a low-tilt abutment surface engageable with the upper surface of the transom bracket when the holding member is in the low-tilt position and extending perpendicularly to a radial plane extending through the second axis and at a first radial distance from the second axis, a high-tilt abutment surface engageable with the upper surface of the transom bracket when the holding member is in the high-tilt position, which high-tilt abutment surface extends perpendicularly to a radial plane through the second axis and at a second radial distance from the second axis greater

Abstract: A marine propulsion device comprising a lower unit, a propeller shaft rotatably supported by the lower unit and adapted to support a propeller, an engine supported by the lower unit and drivingly connected to the propeller shaft, and a cowl assembly surrounding the engine and including a lower cover member having an upper end, an upper cover member having a lower end, a seal located between the upper end and the lower end, and interengaging mechanisms on the seal and on one of the upper and lower cover members for securing the seal to the one of the upper and lower cover members.

Abstract: Disclosed herein is a marine propulsion device comprising a transom bracket adapted to be mounted on a boat transom and including a pair of laterally spaced elements, a swivel bracket supported from the transom bracket for pivotal movement about a horizontal tilt axis and through a trim range and a tilt range extending upwardly from the trim range, which swivel bracket includes a portion which extends generally vertically when the swivel bracket is in the trim range and which includes an unbroken rearward surface extending between the transfer bracket elements and a projection extending forwardly therefrom, a roller supported by the projection for rotation about a horizontal axis parallel to the tilt axis, a hydraulic tilt and trim assembly comprising a tilt hydraulic cylinder/piston assembly comprising a tilt cylinder pivotally connected to the transom bracket and a tilt piston rod pivotally connected to the swivel bracket, and a trim hydraulic cylinder/piston assembly comprising a trim cylinder fixedly conn

Abstract: An outboard motor comprising a propulsion unit having opposite first and second sides and including a lower unit including a rotatably mounted propeller, and a drive shaft housing including a drive shaft drivingly connected to the propeller, and a power head mounted on the drive shaft housing and including an internal combustion engine drivingly connected to the drive shaft, a cowl assembly enclosing the power head and including a first lower cowl member removably and resiliently mounted on the first side of the propulsion unit, a second lower cowl member removably and resiliently mounted on the second side of the propulsion unit, and an upper cowl member removably mounted on the first and second lower cowl members, and a bolt detachably connecting the first lower cowl member to the second lower cowl member.

Abstract: A marine propulsion device comprising an internal combustion engine including a coolant conduit having an upstream conduit portion, a downstream conduit portion, and a passage portion extending between the upstream portion and the downstream portion.

Abstract: A connecting assembly comprising a support including spaced-apart sides, and a bore extending between the sides, a first member slideable in the bore, and including a first portion located on one side of the support, and a second member including an opening therein. The connecting assembly also includes a connecting device adjacent to one side of the support for connecting the second member to the first portion of the first member and comprising a first piece fixedly connected to the first portion, and a second piece located between the first piece and the one side of the support. The second piece also includes a bore which receives the first member for movement thereof relative to the second piece between a connect position with the first piece adjacent the second piece and a disconnect position with the first piece spaced from the second piece.

Abstract: Disclosed herein is an engine block including first wall portions defining a combustion chamber, second wall portions defining a bore including a first portion extending from the combustion chamber and a second portion enlarged with respect to the first portion, third wall portions defining a water jacket in cooling relation to the second wall portions, and an elongated duct of heat resistant material communicating through the first bore portion with the combustion chamber so as to receive exhaust gases discharged therefrom, which duct is circumferentially engaged by and supported from the second wall portion at locations spaced lengthwise of the duct and extends in the enlarged bore portion in spaced relation from the second wall portions intermediate the locations, whereby there is provided a stagnant air space between the duct and the block intermediate the locations so as to reduce heat transmission from the duct.