Abstract: A cover structure of an upper unit in which a power source of an outboard motor is provided, the cover structure includes a main body cover including a pair of divided covers connected to each other, the pair of the divided covers being configured to be divided into each other in a left-right direction with respect to a traveling direction of a boat, and an attachable and detachable cover that is attachable to and detachable from a part of an outer surface of at least one of the pair of the divided covers.

Abstract: A device and technique for reducing noise experienced by boat passengers from an outboard boat motor is discussed. The device may be implemented in the form of a cover that is adjacent to at least a portion of the boat motor. The cover includes one or more walls or surfaces that reflect or attenuate soundwaves. The cover may be attached to the boat motor and/or the boat. The cover may be integral with the boat motor and/or the boat. The cover may be attached to the boat via a hinge to permit the cover to be pivoted away from the boat motor. The materials used to construct the cover may be provided in layers that help to attenuate, absorb or reflect soundwaves.

Abstract: Embodiments include apparatuses, systems and methods for a computer device with a casing and a substance in the casing substantially surrounding a computer component in the casing. In embodiments, the computer device may be a command and control computer, such as for example, an autonomous or semi-autonomous vehicle. In embodiments, the substance may be an electrically isolative and shear-thickening fluid to provide thermo-mechanical protection to a computer component. In the described embodiments, the substance may dampen mechanical shock or vibrational impact on the processor and the memory. The shear-thickening gel may further be thermally conductive in embodiments. In the embodiments, the casing may be substantially filled with the substance and the substance is to conduct heat away from the processor and the memory toward an outer edge of the casing. Other embodiments may also be described and claimed.

Abstract: A cowling for an outboard motor extends from port side to starboard side in a lateral direction. The cowling includes port and starboard inlets that direct flow of intake air into the cowling and face outwardly in the lateral direction. The cowling further comprises port and starboard duct systems. Each duct system is configured to receive and convey intake air from one of the port and starboard intake ports to an intake conduit for the outboard motor. Each duct system defines a first separation region that receives and conveys the intake air laterally outward to separate a first portion of water from the intake air. Each duct system further defines a second separation region that receives and conveys the intake air from the first separation region laterally inward to separate a second portion of water from the intake air.

Abstract: A vehicle includes an engine, an engine cover, and a cross component. The engine cover has a through-hole through which the cross component passes. The cross component is a flexible hose or a flexible pipe in which a body part extending in a cross direction is integrated with a diameter enlarged part having a diameter larger than the body part. The outer peripheral part of the diameter enlarged part makes close contact with the inner peripheral surface of the through-hole of the engine cover.

Abstract: An outboard engine cover structure that covers an outboard engine and includes an inner cover on an inside and an outer cover on an outside. The structure includes a flow space for air formed between the inner and outer covers, an intake formed in a lower portion of the outer cover and configured to take in outer air to the flow space, a communication port formed in the inner cover in a position above the intake, and configured to cause an inner space of the inner cover accommodating the outboard engine to communicate with the flow space, first ribs arranged between the intake and the communication port in the flow space; and second ribs arranged between the intake and the communication port and positioned closer to the communication port than the first ribs in the flow space.

Abstract: An attachment mechanism for electronic equipment for an engine includes a bracket configured to hold the electronic equipment and a plurality of support portions configured to elastically support the bracket with respect to a head cover of the engine. The support portions are disposed such that a maximum distance between two support portions of the support portions in a direction parallel to a shaft center of a crankshaft of the engine is longer than a maximum distance between the two support portions of the support portions in a direction perpendicular to the shaft center of the crankshaft of the engine.

Abstract: A device and technique for reducing noise experienced by boat passengers from an outboard boat motor is discussed. The device may be implemented in the form of a cover that is adjacent to at least a portion of the boat motor. The cover includes one or more walls or surfaces that reflect or attenuate soundwaves. The cover may be attached to the boat motor and/or the boat. The cover may be integral with the boat motor and/or the boat. The cover may be attached to the boat via a hinge to permit the cover to be pivoted away from the boat motor. The materials used to construct the cover may be provided in layers that help to attenuate, absorb or reflect soundwaves.

Abstract: An air cleaner includes a housing and a filter element located within the housing. The housing includes a housing body and a fiber molding assembly. The housing body is formed by a plastic molding. The housing body has a wall located upstream of the filter element in an air flow direction and a recess, which is an inwardly recessed part of the wall. The fiber molding assembly is fixed to the wall, covers the recess from outside, and forms a part of a side wall of an inlet passage together with the recess. A communication hole for communication between the inlet passage and an interior of the housing body is formed in the recess.

Abstract: A supporting member includes a first plate portion including a supporting surface, a first hole, and a female thread portion formed at an inner peripheral surface of the first hole; a second plate portion provided by hemming the metal plate member; a third plate portion provided by bending the metal plate member at one end portion of the second plate portion at substantially a right angle; and a second hole continuing between the second and third plate portions so that the screw threadably engageable with the female thread portion is prevented from interfering with the second and third plate portions. The second and third plate portions provide a bent portion therebetween positioned within a range of a nominal diameter of the female thread portion with respect to a thickness direction of the third plate portion, as seen in a direction perpendicular to the thickness direction.

Abstract: An outboard motor includes an engine, an engine cover accommodating the engine, and an intake path between the engine cover and the engine. The intake path directs external air to the engine. The engine cover includes an upper cover and a lower cover. The upper cover includes an opening to take external air into the intake path. The intake path includes a first airflow passage, a second airflow passage, and an airflow space. The first airflow passage is at least partially defined by an inner surface of the engine cover, and downwardly directs the external air. The second airflow passage is at least partially defined by the inner surface of the engine cover, and upwardly directs the external air. The airflow space is above the lower cover and continues to the first airflow passage and the second airflow passage.

Abstract: Combustion air intake ports are provided on left and right side faces of an upper part of an engine cover. An outer louver is disposed to confront the combustion air intake port, and an inner louver is disposed inward of the outer louver at a predetermined interval to face the outer louver. The combustion air received from the combustion air intake port passes through the outer louver and the inner louver and is guided to the engine unit from the guide hole. In this case, a splash of water is dispersed in the outer louver, and a large-sized water droplet falls down due to its self-weight before the combustion air reaches the inner louver, so that a small-sized water droplet can be collected and removed using inertial impaction at the inner louver. Therefore, it is possible to effectively separate water.

Abstract: 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.

Abstract: An outboard motor has an adapter plate with an upper surface supporting an engine, a lower surface spaced therefrom, and fore and aft sides connecting the upper and lower surfaces. A first pocket is defined in the adapter plate's fore side and a second pocket is defined in its aft side. A midsection housing is coupled to the adapter plate's lower surface and suspends a propulsion unit therebelow. A driveshaft coupling the engine's output shaft to the propulsion unit's propeller shaft extends through the adapter plate. A steering arm, which extends into the first pocket, has a hole through which the driveshaft extends. A mount in the second pocket is located aft of the driveshaft, and the mount's fore side is coupled to the steering arm's aft end by way of connectors. A cover plate attached to the adapter plate's aft side secures the mount within the second pocket.

Abstract: An outboard motor includes an internal combustion engine powering the outboard motor and a cowl covering the engine and having a vent allowing air under the cowl. A throttle body meters flow of the air into the engine and an intake structure downstream of the throttle body delivers the metered airflow to one or more combustion chambers in a cylinder block of the engine. A sound enhancement assembly in acoustic communication with the intake structure collects sounds emitted by the engine. The sound enhancement assembly is configured to amplify a subset of the collected sounds that have frequencies within a desired frequency range. A method for modifying sounds produced by an air intake system of an internal combustion engine powering an outboard motor is also disclosed. The method includes positioning a sound enhancement assembly in acoustic communication with an air intake passageway located downstream of the engine's throttle body.

Abstract: [Problem] To perform an assembling operation easily while attaining improvement in engine efficiency. [Solution] An outboard motor 10 according to the invention includes an upstream side duct 42 which is fixed to an engine upper cover 27, and a downstream side duct 43 which is fixed to an engine 14 side. The upstream side duct 42 includes an exhaust port 52 which is opened at its side face. The downstream side duct 43 includes a downstream side lower duct 59 and a downstream side upper duct 60. In the downstream side lower duct 59, a suction port 61 is provided at a position opposed to the exhaust port 52 and separately at a predetermined distance from the exhaust port 52. In the downstream side upper duct 60, an exhaust port formed toward a throttle body 36 of the engine 14 is provided above the downstream side lower duct 59. The upstream side duct 42 and the downstream side duct 43 are formed so as not to interfere with each other when the engine upper cover 27 is moved vertically.

Abstract: An air intake structure for an outboard engine wherein air which is taken in from an air intake opening provided in an engine cover for covering the upper part of the outboard engine is supplied to and sucked into a throttle body. The engine cover has an air intake opening which is open at the front of the outboard engine in the forward movement direction and a lid member which can open and close the air intake opening. A space which connects the air intake opening and the throttle body is provided separated from an engine room.

Abstract: An outboard motor includes: an engine cover having an upper cover and a lower cover which form an engine room and which can be separated from each other vertically; a ventilation fan for ventilating the engine room; and a fan cover which covers the ventilation fan, the engine cover is configured so that the upper cover is able to be attached to and detached from the lower cover and the lower cover is fixed to an outboard motor main body including an engine, the lower cover has an external air inlet through which to take air into the engine room and a discharge outlet through which to discharge air from the engine room, the fan cover has an air outlet through which to cause air that is sent from the ventilation fan to flow out, and the discharge outlet is connected to the air outlet.

Abstract: An outboard motor adapter plate couples a marine engine to a driveshaft housing, and includes an upper rim configured to be coupled to a lower surface of a cylinder block of the engine. A lower rim of the adapter plate is configured to be coupled to an upper surface of a sump located in the driveshaft housing. A wall defines a passageway having an inner perimetral surface, and the inner perimetral surface extends from the upper rim to the lower rim. A mounting area is configured for coupling a mount to the adapter plate. A shield covers at least a portion of the inner perimetral surface adjacent the mounting area, so as to at least partially thermally isolate the mount from heated fluid that drains from the cylinder block, through the passageway, and into the sump. A method and a shield for thermal isolation are also described.

Abstract: A boat propulsion device includes an engine including a crankshaft extending in an up-and-down direction and a cowling accommodating the engine. The cowling includes a first cowling portion preferably made of resin, a second cowling and a coupling mechanism configured to couple the first cowling portion to the second cowling portion. The coupling mechanism includes a first lock portion and a second lock portion. The first lock portion is attached to the first cowling portion. The second lock portion is attached to the second cowling portion and locks with the first lock portion. The first cowling portion includes a cowling main body and a support portion. The support portion preferably has a plate shape. The support portion is erected on an inner surface of the cowling main body, supports the first lock portion, and includes a small thickness section and a large thickness section.

Abstract: An outboard motor including a system for enhancement of a first subset of sounds having a desired frequency, and a method for modifying sounds produced by an air intake system for an internal combustion engine powering the outboard motor are described. The method includes collecting sounds emitted in an area proximate a throttle body of the engine. A first subset of the collected sounds, which have frequencies within desired frequency range, are then amplified. The amplified first subset of sounds are then transmitted to an area outside a cowl covering the engine.

Abstract: A boat propulsion device includes an engine unit, an attachment portion, an electrical component, wiring, a holder, and an engine cover. The engine unit includes an engine, an exhaust pipe, and a coolant passage. The engine includes a crankshaft which extends vertically. The exhaust pipe is connected to the engine. The coolant passage is configured to cool the engine or the exhaust pipe. The attachment portion is provided integrally with the engine unit on the outside of the coolant passage. The electrical component is attached to the attachment portion. The wiring is connected to the electrical component. The holder is connected to the engine unit on the outside of the coolant passage and holds the wiring. The engine cover houses the engine unit, the attachment portion, the electrical component, the wiring, and the holder.

Abstract: An outboard motor has an adapter plate that supports an internal combustion engine, a driveshaft housing disposed below the adapter plate, and a lower cowl. A lower cowl volume is defined between the adapter plate, cowl and driveshaft housing. A lower cowl volume inlet is configured to supply idle relief exhaust gases to the lower cowl volume and a lower cowl volume outlet is configured to discharge idle relief exhaust gases from the lower cowl volume to atmosphere. The lower cowl volume is configured to cause expansion of the relief exhaust gases prior to discharge of the idle relief exhaust gases to atmosphere.

Abstract: A cowl mounting system includes one or more stabilizer fulcrums spaced between front and rear cowl mounts and preloading the cowl to provide cowl stability in the mounted condition. The stabilizer fulcrums also provide port and starboard alignment guides during assembly.

Abstract: 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.

Abstract: A marine outboard engine includes an engine having a front, back, top and two lateral sides. A cowling, covering the engine at least partially, includes a central support structure fixedly connected to at least one of the engine, a swivel bracket, and an exhaust system. The central support structure extending across at least a portion of the front, top and back of the engine defines at least partially a space through which at least a portion of at least one of its lateral sides is accessible. The space is selectively covered by at least one side panel which is at least partially selectively connected to the central support structure and at least partially disconnectable therefrom to reveal the portion of the at least one of the lateral sides of the engine while the central support structure extends across at least the portion of the front, top and back thereof.

Abstract: An outboard engine unit includes a water pump disposed on a lower end portion of an input shaft of a transmission, and left and right cooling water feeding passages interconnecting the water pump and a cooling water inlet of an engine. The left and right cooling water feeding passages are disposed around a plurality of transmission gears disposed on the input shaft of the transmission. A cooling water drawn by the water pump is guided through the left and right cooling water feeding passages to the cooling water inlet.

Abstract: A marine outboard engine has a cowling having at least one rear panel at a rear end of the cowling. The cowling encloses a power head. A plurality of mount points are disposed inside the cowling and adapted for rigidly mounting a tie-bar bracket. Each mount point is rigidly connected to the power head and has a bracket-mounting hole formed therein. The at least one rear panel has defined thereon a visual indication of an area to be removed to create an opening adapted for receiving therethrough a tie-bar bracket mounted on and extending from the mount points. A tie-bar bracket having a mounting portion and a tie-bar coupling portion is also disclosed. A method of assembling the tie-bar bracket in the cowling is also disclosed.

Abstract: A vessel propulsion apparatus includes an engine main body including a crankshaft that is rotatable about a rotation axis extending in the up-down direction, auxiliary machinery mounted on the engine main body, a bracket that couples the auxiliary machinery to the engine main body, and an engine cowling that houses the engine main body, the auxiliary machinery, and the bracket. The bracket includes a first mounting portion mounted on the engine main body, a second mounting portion mounted on the auxiliary machinery, a coupling portion coupling the first mounting portion and the second mounting portion, and a holding portion provided in the coupling portion. The holding portion of the bracket holds piping.

Abstract: In an outboard motor having an engine unit housed in an engine room formed by an exterior cover, a protruding portion is projectingly formed on the upper surface of an engine cover covering the upper portion of the outboard motor, and an outside air inlet opened to face forward is provided at the protruding portion.

Abstract: An outboard engine has a cowling defining an engine compartment, an internal combustion engine disposed at least in part in the engine compartment, a driveshaft operatively connected to the internal combustion engine, and one of a propeller and an impeller operatively connected to the driveshaft. The one of the propeller and the impeller rotates about an axis that is angled relative to the driveshaft. A device is disposed inside the engine compartment. A box is disposed outside the engine compartment and is operatively connected to the engine compartment. A line has a portion disposed inside the box and an end operatively connected to the device. An outboard engine having a box disposed outside the engine compartment and operatively connected to the bracket is also disclosed. A watercraft having the outboard engine is also disclosed.

Abstract: A marine propulsion system is for propelling a marine vessel in water. The system comprises a marine vessel and an outboard motor that is coupled to the marine vessel. The outboard motor has a first inlet that receives intake air for combustion. A second inlet is located on the hull of the marine vessel and a conduit conveys the intake air from the second inlet on the marine vessel to the first inlet on the outboard motor.

Abstract: An outboard engine unit capable of efficiently cooling the interior of an engine cover is disclosed. The outboard engine unit includes a cooling opening capable of guiding air to an interior from an upper part of the engine cover, a first intake channel having a first outlet open to an upper front end and communicating with the opening, a partition wall disposed so as to be oriented substantially in a perpendicular direction below the first outlet; and a second intake channel extending substantially in the perpendicular direction along a rear wall of the engine cover rearward of the partition wall. The outboard engine unit is configured so that air directed from the cooling opening to the interior of the engine cover is directed to the throttle unit via the second cooling air intake channel.

Abstract: In an outboard motor having an engine and an engine cover adapted to cover the engine, the engine having an air intake passage that opens at the engine cover, it is configured such that a secondary air passage having an inlet disposed at an internal space of the engine cover and an outlet connected to the air intake passage at a position downstream of a throttle valve of the engine. The inlet of the secondary air passage is disposed at an internal space of the engine cover and near a belt cover that covers a timing belt adapted to transmit rotation of a crankshaft of the engine to a cam shaft of the engine.

Abstract: An exhaust fan chamber is defined with a belt cover and a fan cover provided over the belt cover, and an exhaust fan is accommodated in the exhaust fan chamber. The fan cover has an air intake port for sucking air within an engine cover into the exhaust fan chamber and an exhaust outlet port for discharging air within the exhaust fan chamber to outside of the exhaust fan chamber. The exhaust outlet port is in communication with an exhaust opening formed in an upper portion of the engine cover so that the air discharged through the exhaust outlet port is discharged to outside of the engine cover through the exhaust opening.

Abstract: An apparatus for intake of air to an outboard motor includes an inlet receiving a mixture of air and water from atmosphere surrounding the outboard motor and an outlet discharging the air. A conduit extends between the inlet and the outlet. The conduit has a vertically downwardly oriented first flow path, a vertically upwardly oriented second flow path, and a junction joining the first and second flow paths. The junction is oriented with respect to the first and second flow paths such that both centrifugal and gravitational forces separate the water from the air as the mixture flows therethrough.

Abstract: An outboard motor has an engine, an engine cover forming an engine compartment for holding the engine therein, a ventilation system with an outer outlet ventilation space through which air in the engine compartment flows to the outside of the engine compartment, and a generator. The ventilation system includes a case disposed in the engine compartment and forming an air discharge passage leading to the outer outlet ventilation space. A fan is placed in the air discharge passage to deliver air by pressure from the engine compartment to the outer outlet ventilation space. The air discharge passage has an inlet ventilation passage formed in an upper space in the engine compartment and opening upward. The engine compartment holding the engine therein can be efficiently ventilated, and ventilation air can effectively cool the engine and can effectively suppress temperature rise in the engine compartment.

Abstract: In a electric corrosion preventing structure of a marine vessel propelling machine, a cylinder is integrally formed in a cylinder block, an electric connection portion is provided in a portion in which a rod guide is fixed to the cylinder, an electric connection portion is provided in a portion in which a piston is fixed to a rod in an inner portion of the cylinder, and the piston fixed to the rod strikes against the rod guide in an electrically connected state, at a maximum extension when the rod protrudes out of the cylinder.

Abstract: An outboard motor has an internal combustion engine, an engine cover forming an engine compartment for holding the internal combustion engine therein, and a top cover covering the engine cover from above and provided with a carrying grip. An intermediate member is placed in a space between the engine cover and the top cover. First connecting parts for connecting the engine cover and the intermediate member are arranged in a space between the engine cover and the intermediate member, and second connecting parts for connecting the top cover and the intermediate cover are arranged in a space between the top cover and the intermediate cover. The connecting parts arranged in the spaces between the engine cover and the top cover ensure rigid connection, the degree of freedom of arranging the connecting parts is increased, and the engine cover can be manufactured at low cost.

Abstract: In an outboard motor having an engine unit housed in an engine room formed by an exterior cover, a protruding portion is projectingly formed on the upper surface of an engine cover covering the upper portion of the outboard motor, and an outside air inlet opened to face forward is provided at the protruding portion.

Abstract: An air intake passage system includes an external air intake port provided in a rear portion of a top cover and a passageway section projecting upwardly from the engine cover for directing taken-in external air to the engine. The top cover is provided over the engine cover with a gap therebetween such that the taken-in external air is allowed to flow into the passageway section and a water discharge section is provided between the engine cover and the top cover. Water, having entered together with external air, flows along the upper surface of the engine cover, bypasses the passageway section and is then discharged via the water discharge section.

Abstract: In cowling structure for an outboard motor, a through hole is formed below an upper-cowling joining surface of a lower cowling; control cables are supported with a cable supporting groove of a back side plate, and the back side plate is fixed to the through hole; a sealing member that is covered on the outside of the control cables, is fitted into the through hole; a groove of a front side plate is placed around the control cables, and the front side plate is set onto the sealing member; and the sealing member is fixed to the lower cowling by a bolt together with the front side plate. The cowling structure for an outboard motor can prevent water intrusion by removing a notch on an upper-cowling joining surface of a lower cowling.

Abstract: An outboard motor includes an engine, and a top cowling and a bottom cowling that are arranged to cover the engine. A flow-joining pipe is connected to each exhaust port of a plurality of cylinders of the engine. A first exhaust pipe, a second exhaust pipe, and a third exhaust pipe are connected to the flow-joining pipe in sequence. The flow-joining pipe and the first exhaust pipe are connected generally at the same height as a bottommost of the cylinders of the engine. The third exhaust pipe is disposed above a topmost of the cylinders of the engine. A catalyst is disposed in a connecting portion between the first exhaust pipe and the second exhaust pipe so as to be housed in an upper end portion of the first exhaust pipe and in a lower end portion of the second exhaust pipe. The outboard motor is thus able to prevent water from adhering to a catalyst while avoiding any increase in size.

Abstract: An outboard motor has a top cover extending over an engine cover covering an engine, and an upstream intake silencer spaced upward apart from the top wall of the engine cover. The upstream intake silencer has an entrance duct spaced apart from the top wall and forming an inlet air passage through which air for combustion flows from an air-intake space into the upstream intake silencer. The upstream end of the inlet air passage is on the rear side of the downstream end of an outlet air passage and at a level above that of an air-intake opening. The entrance duct does not extend downward from a bottom wall forming the upstream expansion chamber and protrudes upward from the bottom wall in the upstream expansion chamber.

Abstract: An engine is disposed in a top cowling. Burned gas produced in the engine is discharged to the outside through a first exhaust pipe, a second exhaust pipe, a third exhaust pipe, exhaust passage, and a exhaust passage. A catalyst is disposed to be housed in the first exhaust pipe and the second exhaust pipe. The first exhaust pipe and the second exhaust pipe are disposed in the top cowling. A fan is provided above the catalyst. As a result of this unique structure, a temperature increase in the cowling is prevented from being caused by heat radiated from the catalyst.

Abstract: A hook assembly is arranged to engage with an engaged member to fix a first housing to a second housing of an outboard motor. The hook assembly includes a rotation shaft, a hook member, a lever, and a weight. The rotation shaft is rotatably mounted on the first housing. A recessed portion is provided in the hook member. The recessed portion is arranged to open in first rotation direction. The recessed portion engages with the engaged member. The lever extends from the rotation shaft in a second rotation direction opposite to the first rotation direction of the recessed portion. The weight regulates the rotation of the hook member in the second rotation direction when the hook member and the engaged member are engaged together. The arrangement provides a highly-operable hook assembly for the outboard motor that prevents disengagement even when an obstacle collides with the outboard motor during traveling of a boat.

Abstract: An outboard motor having an engine cover formed from a lower cover fixed to a casing and an upper cover joined to the lower cover at a first mating surface. A linear member lead-out part is formed from a case part integrally connected to the lower cover. The linear member lead-out part is closer to one side wall and projects forward from a front wall of the lower cover. A lid member is joined to the case part by a second mating surface disposed below the first mating surface. A water entrance chamber is formed in the lower cover and has front and rear walls defined by a pair of wall portions integrally provided with the lower cover while being spaced in a fore-and-aft direction. The water entrance chamber is disposed on the side on which a small gap is formed between the lid member and the lower cover.

Abstract: An outboard motor intake port system includes an internal cover mounted, from the inside, on an engine cover to form an intake chamber between the internal cover and the engine cover. The internal cover is integrally provided with a bottom plate portion facing the inner face of an upper part of the engine cover, a front wall portion extending upward from a front edge of the bottom plate portion and connected to the inner face of the upper part of the engine cover, and a pair of tubular portions extending upward from the bottom plate portion. The pair of tubular portions are arranged side by side so water that has entered the intake chamber via an intake port passes through the tubular portions. A pair of drain holes for discharging water are formed in the engine cover and communicate with the left and right front parts of the intake chamber.

Abstract: A seal member seals a gap between upper and lower cover members of an engine cover of an outboard motor. The seal member includes a supporting portion and a sealing portion integral with the supporting portion. The supporting portion has such a high spring modulus that the supporting portion is not plastically deformed with a load is applied to the supporting portion when the upper cover member is locked to the lower cover member. The sealing portion is hollow and has such a small spring modulus that the sealing portion can readily flex into close contact with the upper and lower cover members so as to provide an improved seal between the upper and lower cover members.

Abstract: An air intake passage system includes an external air intake port provided in a rear portion of a top cover and a cylinder section projecting upwardly from the engine cover for directing taken-in external air to the engine. The top cover is provided over the engine cover with a gap therebetween such that the taken-in external air is allowed to flow into the cylinder section and a water discharge section is provided between the engine cover and the top cover. Water, having entered together with external air, flows along the upper surface of the engine cover, bypasses the cylinder section and is then discharged via the water discharge section.