Abstract: A water pump has a bowl like body and a seal across the rim of the body. Coolant leakage through the seal is used to wet the rubbing faces of the seal. Superfluous leakage is collected in the bowl so that it may be evaporated by engine heat.

Abstract: The present invention discloses a structural oil pan for use with an internal combustion engine having a crankcase with short side walls of the type that generally do not extend below the center line of the crankcase. The oil pan has internal ribs which slidingly receive lower portions of the main bearing caps. The main bearing caps are fixed, relative to the oil pan with bolts passing through openings in the pan to threadingly engage corresponding openings in the bearing caps. Such an oil pan design allow the crankcase side walls, the crankshaft main bearing caps and the oil pan side walls to be structurally joined to resist vibration and noise generation. Weight savings are recognized by the oil pan of the present invention as the need for an engine block having extended side walls and increased weight is supplanted by a light weight, structurally rigid oil pan.

Abstract: A wiring arrangement for an outboard motor including a printed circuit board fitted within a magneto generator cover that is secured to the top of the engine of the outboard motor overlying the rotor. The printed circuit board has projecting portions that extend radially outward from a generally disk-shaped body for coupled connection with branch wires, one of which acts as an output line extending from a remote control unit within an associated watercraft. The other branch wires extend downwardly to supply power to various electrical components of the outboard motor.

Abstract: The present invention provides an improved cowling and air inlet arrangement for the powerhead of an outboad motor, having an internal combustion engine including an induction system, which will prevent water from splashing upon the outer surface of the engine contained therein. Damage to the engine due to corrosion, or other such phenomena is avoided, since the arrangement of the invention does not permit water to impinge upon the engine.

Abstract: A split oil pan is arranged for permitting removal of a rear sump portion relative to a front sump portion to accommodate access interiorly of a crank case of an associated internal combustion engine. The oil pan includes a rear sump portion forward flange cooperative with a forward sump portion rear flange securable together by use of a fastening pan member.

Abstract: A plurality of engine transmission assemblies for powering vehicles wherein the engine is provided with an integral crankcase transmission assembly that is made up of first, second and third pieces that are connected to each other. The first and second pieces meet along a plane in which the axis of rotation of the engine crankshaft lies. The third piece is affixed to the first and second pieces along a plane that is perpendicular to the first plane and which contains the axis of rotation of the transmission primary shaft and either the transmission secondary shaft or the transmission shift shaft. The constructions have high rigidity and also ease of servicing.

Abstract: A V-type internal-combustion engine has two banks of cylinders, each with a cylinder-head housing which is covered by cylinder-head cover and, on each end face, by an end cover. Camshafts are driven via chain wheels by a common chain which is led through a free space between the two banks of cylinders in a well housing. To reduce jumps in sealing surfaces which present sealing problems, the well housing is arranged at a distance from the parting planes between the cylinder-head housings and cylinder-head covers and is fastened solely between the cylinder-head housings and the end covers.

Abstract: An oil pan construction for an internal combustion engine having a skirt portion defining a downwardly facing opening and a blanking plate that is affixed to the skirt portion by threaded fasteners which also affix the skirt portion to the cylinder block.

Abstract: A delay part for lubricating oil is arranged in the power section of an internal-combustion engine adjacent to a or in an area bordering on the oil pan. The part prevents the immediate intake of foamed oil in that it has oil passages along its boundary but otherwise separates the spaces situated above and below the delay apparatus from one another. The oil reaches the strainer in a time-delayed manner and is therefore effectively degassed.

Abstract: An oil pan held on a crankcase of an internal-combustion engine has a flat, plate-type bottom and an oil sump. The flat bottom is connected by means of supports directly to central bearing seats of the crankshaft. This significantly improves the sound radiation of the oil pan and the rigidity of the bearing seats.

Abstract: An I.C. engine lubrication system comprises a gerotor pump set driven by a gear meshed with another gear on the crankshaft (FIG. 1). This enables pump diameter to be selected for minimum power absorption as compared with prior art arrangements where the gerotor surrounds the crankshaft, and also simplifies pipework particularly on the delivery side of the pump.

Abstract: An internal combustion engine comprises a cylinder block including a front wall, and a chain cover attached to the front wall. Coolant passage walls defining a coolant passage are integrated with the front wall of the cylinder block and the chain cover, respectively. Heat insulating means are arranged to prevent a contact of lubricating oil and blow-by gas with the coolant passage walls.

Abstract: An oil guiding housing is arranged below the crankcase of an internal-combustion engine and has a storage tank for lubricating oil and a housing part with a connection for an oil filter. In the pan part of the oil guiding housing situated directly below the crankshaft, a forward flow and return flow part for lubricating oil is integrated. The oil guiding housing ensures a targeted guiding of all lubricating oil flows and provides a good degassing of the oil.

Abstract: An engine cylinder block includes lower and upper cylinder block portions which are fastened together by bearing cap fastening bolts and cylinder block fastening bolts. The engine cylinder block is provided with a baffle plate, for separating a crankcase from an oil pan. The baffle plate is fastened to the engine cylinder block by the cylinder block fastening bolts. Bearing cap fastening bolts are arranged in a row parallel to an axis of rotation of the crankshaft at each side of a row of bearing caps. The cylinder block fastening bolts, each of which is located between adjoining bearing caps, are arranged in a row parallel to the axis of rotation of the crankshaft on each side of the row of bearing caps.

Abstract: An accessory drive arrangement for an internal combustion engine having belt driven overhead camshafts contained within a belt cover. An accessory mounting boss is affixed to the engine within the belt cover and has a boss portion that extends through the belt cover and which journals an accessory drive idler pulley.

Abstract: A marine propulsion device comprising a propulsion unit including an internal combustion engine, a shroud substantially enclosing the engine, and a duct having a first end communicating with the shroud and an opposite second end being adapted for connection to an opening in the transom of a boat to enable the engine to draw combustion air from the interior of the boat, the duct including a flexible portion and a rigid portion.

Abstract: An oil pan for an internal combustion engine has a relatively flat bottom part as well as a deep pan section as the oil sump with a suction pipe of an oil pump extending into the deep pan section. The deep pan section is designed as a removable oil container. The oil can thus be changed rapidly and without draining the oil since all the oil is collected in the oil container. A cover may be provided to close the container when removed from the shallow flat bottom part. Also, a filter may be mounted in the container and its upper section may be vented to the engine crankcase ventilation system.

Abstract: An improved crankcase gasket, for use in an internal combustion engine with a vertical crankshaft, having web portions that substantially cover the oil sump. The construction of the crankcase gasket baffles oil thrown around the inside of the engine by mechanical turbulence and prevents excess oil from reaching the cylinder bore. Gasket material under the valve spring box drain operates as a check valve and eliminates the need for an expensive valve stem valve. Oil temperature is reduced with an increased ability for engine operation at greater angles of crankshaft tilt from vertical.

Abstract: The design and construction of present oil pan assemblies have caused increased manufacturing cost, reduced seal life and reduced engine reliability. The present invention overcomes these oil pan assembly construction problems by using an oil pan assembly including a thin walled structure having a drain port formed therein. The thin walled structure further has a frusto-conical contoured lip around the drain port being concave toward the inside surface. The frusto-conical contoured lip has a sealing surface on the portion of the outside surface forming the frusto-conical contoured lip. A reinforcing member having a threaded hole therein and a conically contoured support surface at one end of the threaded hole is positioned so that the threaded hole is generally centered about the drain port. The support surface is located in supporting relationship to the frusto-conical lip. A drain plug having a threaded end and a sealing surface also includes an O-ring seal removably attached to the drain plug.

Abstract: A two-stroke engine with crankcase compression has a hose (17) with an inlet duct (18) to the engine block of a chain saw with a partition wall (15) between an engine and a carburetor room (14). The hose runs from the carburetor through the wall to the engine block and is provided with a flange (20) squeezed between the wall and the carburetor which attached by set screws to the wall. In the same hose (17), a hollow passage (19) runs from the crankcase to the fuel pump of the carburetor.

Abstract: An oil pan for an internal combustion engine wherein the oil dropped on a shallow bottom section is rapidly returned into a sump. A plurality of guide ribs are disposed on the downstream side of the shallow bottom section which is located at the downstream side of the oil flow caused by the rotation of a crankshaft of the engine. The guide ribs are formed in an arcuate shape so as to curve toward the sump as they approach a side wall located at the downstream side, by which the oil flow is directed toward the sump. Additionally, a guide plate formed integrally with a baffle plate extends upwardly to guide the flowing oil into the sump.

Abstract: A trough shaped engine cover is arranged for mounting to a top portion of an overhead valve internal combustion engine. The valve cover includes a series of spaced boss members directed through a top wall of the valve cover, with each boss member defining a conduit mounting a removable plug assembly removably mounted relative to the conduit. Each conduit is coaxially aligned with a fulcrum portion of a rocker arm of the overhead valve assembly to permit access to the fulcrum by an adjusting wrench.

Abstract: An air intake system for an internal combustion engine associated with the power head of an outboard marine propulsion system. The engine includes a vertical crank shaft and a flywheel mounted to the crank shaft above the engine block. An air manifold is mounted to the forward side of the engine, and includes an air inlet for receiving intake air. The air intake system includes an air flow path or duct defined by a series of walls, a rearwardly facing air intake opening and a discharge opening for supplying intake air to the air manifold inlet. The engine is enclosed within a cowl assembly, and the air intake opening is located toward the upper end of the cowl assembly interior. The walls defining the air flow duct are formed integrally with a flywheel cover for facilitating assembly of the air flow duct to the engine. The air flow duct minimizes ingestion of water into the engine and reduces engine noise in the boat.

Abstract: A cylinder block for an internal combustion engine, comprising: (a) a siamesed cylinder sleeve unit (steel or metal matrix composite) having an annular tongue flange spaced above but adjacent the bottom of the unit; and (b) a plastic jacket (phenolic, vinyl ester, or epoxy) spaced from but surrounding the sleeve unit and having the tongue flange molded integrally with the jacket, the sleeve unit and jacket being adapted for closure by a head having a wall to mate with the planar top of the sleeve and jacket; and (c) sealant deposited at interfacing surfaces of the sleeve unit and jacket which are integraly molded, the sleeve being constituted of a metal-based material having a thermal expansion characteristic differing from the plastic jacket by no greater than 25%.

Abstract: An internal combustion engine comprising an engine block including an outer surface, structure including the engine block and a member connected to the surface of the engine block for defining a substantially closed chamber, a crankshaft extending from the engine block and into the chamber, a flywheel located in the chamber, connected to the crankshaft, and including thereon a starter gear, a stator located in the chamber and fixed to the engine block, a magnet or magnets located in the chamber and fixed to the flywheel for rotation therewith in a path adjacent to the stator, a finned coolant jacket located in the chamber and adapted to be connected to a source of coolant exterior to the chamber, structure on the flywheel for creating air flow in a path extending between the stator and the coolant jacket, a starter motor mounted on the block exteriorly of the chamber and including an output shaft extending into the chamber through the member, and a mechanism locatd in the chamber, drivingly connected to the o

Abstract: A marine propulsion device comprising a propulsion unit including an internal combustion engine, a shroud substantially enclosing the engine, and a duct having a first and communicating with the shroud and an opposite second end being adapted for connection to an opening in the transom of a boat to enable lthe engine to draw combustion air from the interior of the boat, the duct including a flexible portion and a rigid portion.

Abstract: An improved drive unit and suspension arrangement therefor for a small snowmobile having an open tubular frame. The drive unit includes an internal combustion engine and a pulley type transmission. The pulley type transmission is supported within a transmission casing and is affixed to the frame for rigidifying the frame. The suspension permits more vertical compliance than for and aft compliance for vibration dampening without adversely effecting the rigidity.

Abstract: An improved rocker box cover assembly for an overhead valve, horizontal crankshaft, internal combustion engine. The cover assembly is a pre-assembled unit attached to the cylinder head and includes an inner cover section, which defines a rocker arm chamber, and an outer cover section with the space between the sections defining an oil separating chamber. The inner cover section is provided with an opening that provides communication between the chambers and a check valve is mounted in the opening. A gas outlet is located in the upper portion of the oil separating chamber while a drain opening is located in the lower end of the separating chamber and separated oil drains through the drain opening and is returned to the crankcase.

Abstract: An oil pan for an internal combustion engine having an engine lubrication system. The oil pan comprises a shallow bottom section and a sump. The shallow bottom section includes an inclined surface which gradually becomes lower in level toward the sump and toward the downstream of the oil flow caused by the rotation of the crankshaft. Therefore, the lubrication oil dropped on the shallow bottom section is effectively returned into the sump through the lower side of the inclined surface under the action of a force caused by the rotation of the crankshaft or the like.

Abstract: A rigid maintenance cover is mounted under the hood, on top of the engine of an automotive vehicle. The cover protects the user while checking various fluid levels, such as the oil, brake fluid, and so forth. The inlet ends of the various conduits for checking such fluids extend above the cover.

Abstract: A cooling system for a V-type engine includes a radiator, having inlet and outlet conduits extending between the radiator and the engine, which cools coolant introduced therein through the inlet conduit, and a water pump with an inlet port, disposed between the engine body and the radiator, which circulates the coolant, leaving the radiator through the outlet conduit, through the engine body. Between the radiator and water pump, the cooling system is provided with a bypass passage, which communicates a passage, connecting both of the outlet ports to the inlet conduit, with a downstream part of the outlet conduit where a thermostat is installed, and a suction passage which communicates the inlet port of the water pump with the downstream part of the outlet conduit by a suction passage.

Abstract: An internal combustion engine having a reinforced cylinder block, a skirt portion integrally formed therewith at a lower portion thereof, a plurality of bearings received therein, a crank shaft journaled in the bearings, a plurality of bearing caps secured to the bearings, and front and rear covers formed at front and rear portions of the cylinder block, respectively, and having respective openings through which the crank shaft extends. In order to reinforce the cylinder block, a reinforcing member is secured to a lower surface of the skirt portion of the cylinder block and to a lower surface of the rear cover. At least two first bolts for fastening the reinforcing member to the lower surface of the rear cover are provided on opposite sides of the rear cover while at least two second bolts for fastening the reinforcing member to a bearing cap for a rearmost bearing of the bearings are placed within a pitch of the first bolts in a direction transversely of the cylinder block.

Abstract: A drive system for a vehicle (V) provided with a power plant (P) which includes an engine (1), a transmission (3) and a differential device (D). The engine is located longitudinally of the vehicle with the crankshaft extending front-to-rear of the vehicle. The power plant drives left and right drive wheels disposed on opposite sides of the engine. The engine has a cylinder axis (L.sub.1 --L.sub.1) inclined to the left or right of the vehicle and includes a cylinder block (6) and an oil pan (13) between which is interposed a lower case (9). The cylinder block and the lower case are joined together at joining surfaces thereof on a plane which extends through the center (O) of the journal bearings (10) for the crankshaft as well as perpendicular to the cylinder axis. The differential case (17) is connected to the lower side face of the engine on the side of inclination of the engine.

Abstract: A V-type engine includes first and second camshafts rotatably mounted to cylinder heads, respectively. A first chain drivingly interconnects a crankshaft and the first camshaft, whereas a second chain drivingly interconnects the crankshaft and the second camshaft. First and second tensioners provide the tensions to the first and second chains, respectively. For concealing the first and second chains, the engine has a cover formed with two openings positioned in accordance with the first and second tensioners.

Abstract: In a DOHC engine, a sprocket chamber is formed at the cylinder head at one end thereof, and formed with a lateral opening. A timing chain drivingly interconnects a crankshaft and an idler gear, whereas a camshaft driving chain drivingly interconnects the idler gear and a pair of cam sprockets. A first tensioner is mounted to a cylinder block for adjusting the tension of the timing chain, whereas a second tensioner is mounted to the sprocket chamber for adjusting the tension of the camshaft driving chain. There are provided means for defining an access to the first tensioner.

Abstract: A cylinder block is detachably connected to a transmission casing so that an engine and a transmission constitutes a single unit. A crankshaft is entirely supported on the cylinder block. A crankshaft gear is installed on the crankshaft at the nearly central portion thereof. An intermediate shaft with an idler gear and an idler shaft with an input gear are entirely supported on the transmission casing in such a way that the idler gear and input gear are meshed with each other. The crankshaft gear and idler gear are automatically meshed with each other when the cylinder block is installed in place on the transmission casing.

Abstract: To reduce the size and weight and the number of parts required for a chain cover apparatus for an engine, the chain cover for covering a chain for transmitting a rotational force of a crankshaft to at least one camshaft mounted on a cylinder head comprises a chain cover formed with a cylindrical hollow projection portion extending frontward and having a hole through which the crankshaft is passed, and an oil pump accommodated within the cylindrical hollow projection portion and driven by the crankshaft. Further, the chain cover is formed with a semicircular flange portion formed at a lower wall of the cylindrical hollow projection portion so as to be joined with an oil pump, and with two flat flanges formed on both sides of the cylindrical hollow projection portion so as to be joined between the oil pan and the engine block.

Abstract: A cover for use on the forward, timing chain, end of a number of different model multi-cylinder, automotive vehicle type internal combustion engines is formed of an integral cast metal dish-like shape having a forward wall and a surrounding edge wall which define a cavity. The edge wall is shaped to engage and mount upon the forward end of an engine to cover the timing chain and the engine crankshaft extends through a seal mounted within a hole in the wall, with the seal being located upon the exterior of the cover wall for removal without removing the cover. A fuel pump mounting opening, which may be blocked by a removable plate, is formed in the cover edge wall so that a fuel pump may be optionally mounted within the cover by removing the plate. A distributor mechanism receiving opening is formed in the upper end portion of the cover edge wall and alternative screw receiving holes formed in the cover permit mounting different, preselected distributor mechanisms therein.

Abstract: A two wheel motorcycle of the scooter type employing a power unit with an engine mounted forwardly of the rear wheel, a power train extending rearwardly on one side of the rear wheel to couple the engine and the rear wheel and a muffler extending along the other side of the rear wheel. A carburetor is mounted above the power train and an air cleaner for that carburetor is mounted above the muffler. A connecting tube extends transversely of the vehicle between the air cleaner and the carburetor at a lcoation above and forwardly of the axis of the rear wheel.

Abstract: To scavenge blow-by gas blown into a crank case with newly introduced external air at high replacement efficiency and further to provide oil separating baffle plates at both the main oil-separation passage and the subsidiary oil separation passage (used when blow-by gas follows in the reverse direction from the external air outlet to the external air inlet), the external air outlet and the blow-by gas inlet are located in diagonally furthest positional relationship with respect to each other within the cylinder head cover; and further a U-shaped blow-by gas passage including the main oil-separation passage is arranged on one longitudinal space of the head cover and another U-shaped external air passage including the subsidiary oil-separation passage is also arranged on the other longitudinal space of the head cover.

Abstract: An oil pan for an internal combustion engine having an engine lubrication system. The oil pan comprises a shallow bottom section and a sump section. A guide plate is secured at an inner surface to which a crankshaft splashes lubrication oil carried into the shallow bottom section. The guide plate having an inclined and a guide parts extends generally along the axis of the crankshaft and extends generally parallel with a horizontal plane. The inclined part which gradually becomes high in level in the direction toward the sump is continuously connected to the inclined part to be formed in a generally arcuate shape. Therefore, the splashed oil at the inner surface cannot over the guide plate, and the oil is positively returned into the sump section by the guide plate. Accordingly, lubrication in this engine is smoothly carried out without causing a lack of the oil in the sump section.

Abstract: The outboard motor includes an engine driving a propeller. The engine cover includes an upper dome-like cover sealingly connected to a lower pan-like cover. A combustion air opening through the upper portion of said upper cover has a partition inside the opening requiring entering air to travel upwardly into a chamber between a baffle between the inside of the upper cover and the cover. The baffle includes a portion cooperating with the cover to define a downwardly directed duct leading air towards said lower cover clear of the engine. The engine draws combustion air from the region of the lower pan to a higher elevation at the front of the cover while entrained water is deposited in the lower cover a pump discharges the water.

Abstract: An internal combustion engine is disclosed, which comprises a cylinder block having lubrication oil passages formed therein, the oil passages having a cylinder block opening at one longitudinal end of the cylinder block; a crankshaft operatively installed in the cylinder block, the crankshaft having one end portion exposed to the outside of the cylinder block from the one longitudinal end of the same; and a front cover structure attached to the one longitudinal end of the cylinder block.

Abstract: A cylinder head for an overhead camshaft engine comprises an end wall to which an idler is rotatably mounted, and two side walls which extend in generally parallel from the end wall. Upper and lower beams interconnect and extend between the two side walls. The side walls, and the upper and lower beams cooperate with each other to define a mounting site extending to surround a window opening. A cover is detachably mounted on the mounting site to conceal the window opening.

Abstract: A camshaft driving arrangement for a DOHC engine comprises two pairs of sprockets, each pair being mounted to the adjacent pair of camshafts, and two idler gears rotatably mounted to the cylinder banks, respectively. A timing chain drivingly interconnects the crankshaft and the two idler gears. On the other hand, two camshaft driving chains each interconnect one of the two idler gears and the adjacent two cam sprockets. A front cover is so constructed and arranged as to conceal the two idler gears and the timing chain.

Abstract: A water-cooled type internal combustion engine for a farming motor vehicle has a muffler arranged within the space on the lateral side of an engine body disposed in the fore and rear direction of the farming motor vehicle. An exhaust gas dilution pipe is externally fitted at its upper end portion to an outlet pipe of the muffler so as to provide a cooling air passage gap therebetween. The lower end portion of the dilution pipe is extended below the projected end portion of the outlet pipe. A portion of the cooling air delivered by the operation of a radiator fan so as to pass through a radiator is guided by means of a muffler cover so as to be forcedly fed into the dilution pipe through the cooling air passage gap in order to facilitate the dilution of the exhaust gas.

Abstract: A number of embodiments of internal combustion engines incorporating toothed belt driven overhead camshafts. In each embodiment, the driving belt is contained within a protective case that is separated from the engine by an air gap for insulation and a cooling fan driven by the camshaft circulates cooling air through the belt case. All embodiments employ air inlets for the belt case that are disposed in sheltered areas so as to prevent contaminants from being drawn into the belt case. In addition, a generator is contained within the belt case for protection.

Abstract: A novel cover (10) for one end of the casing within which a vehicular transmission is housed and a unique method for making the cover. The cover (10) has a metallic body portion (12) within which a unitary manifold (40) has been cast in situ. The manifold (40) incorporates a plurality of conduits (A-E) which have been preformed and conjoined into the unitary manifold (40) that is precisely disposed within a mold. Molten metal is admitted into the mold to encapsulate the manifold (40) within the metallic body portion (12) of the cover (10). After the cover (10) has been cast, with the manifold (40) encapsulated therein, the cover (10) is removed from the mold, and only a relatively modest amount of machining operations are required to complete the cover (10).

Abstract: The invention relates to internal combustion engines and especially to two-stroke engines for portable handheld work tools such as motor-driven chain saws or the like. Material made of light metal alloys is used in two-stroke engines for portable handheld tools in order to save weight. Thus, the crankshaft bearing is made of steel while the bearing covers holding the bearing are made of a magnesium alloy. Heating causes the bearing cover to expand by an amount greater than the crankshaft bearing whereby the press fit of the crankshaft bearing can become endangered and, in an extreme case, a clearance can develop between the crankshaft bearing and the bearing cover. According to the invention, the press fit between the crankshaft bearing and the bearing cover is maintained by placing a plastic annular segment therebetween having a thermal expansion coefficient so selected that it compensates for the different thermal expansions of the bearing cover and the bearing.

Abstract: A portable work machine equipped with an internal combustion engine. A starting pressure reducing device is mounted on a cylinder of the engine for reducing, at starting of the engine, pressure within a combustion chamber defined in the cylinder. A hole is formed at a portion of an engine cover which is within reach of a finger of a hand holding a handle, and is closed by a flexible cap. An actuating portion of the starting pressure reducing device is disposed inside the cap.