Abstract: In an air cooled overhead valve internal combustion engine, a metal gasket plate is disposed between the cylinder portion and the cylinder head. The metal gasket plate includes apertures for receiving the push rods therethrough and guide tabs disposed on opposite sides of the push rod for controlling lateral displacement of the push rods. The metal gasket plate includes adjacent annular stepped portions extending alternately in opposite directions out of the plane of the gasket plate adjacent the periphery of the aperture. Cylinder head bolts are received through the cylinder head and threadedly received in the cylinder portion and pass through the metal gasket plate. Dish shaped spring washers are provided between the cylinder head and the underside of the head portion of the cylinder head bolts.

Abstract: An air-cooled internal combustion engine having a rotating screen and a blower housing surrounding the screen. A ring is attached to the housing and positioned circumjacent the screen to define a precisely gauged radial clearance gap between the ring and the rotating screen. The ring provides a tortuous entry path for foreign matter entering through the air intake port between the ring and the screen. The ring includes a downwardly extending groove into which extends an upwardly turned lip of the rotating screen to form the tortuous path for foreign matter entering through the clearance gap between the inner periphery of the ring and the outer periphery of the main portion of the screen. Large debris and foreign matter entering through the tortuous path is chopped up into small pieces, which may then pass through the cooling fins.

Abstract: The invention relates to a mounting arrangement for a fuel tank and shroud unit on an internal combustion engine. The plastic shroud unit includes a fuel tank and outer walls extending around the crankcase. The shroud unit is clamped to the crankcase by two springs disposed on opposite sides of the crankcase. In addition, the shroud unit and crankcase have complementary mounting surfaces for supporting the shroud unit on the crankcase.

Abstract: An air-cooled internal combustion engine, a crankshaft and a camshaft rotatably journalled in the crankcase parallel to one another, and a cast intake valve chamber and cast exhaust valve chamber each cast integrally with the cylinder and communicating with the combustion chamber via a respective intake valve port and exhaust valve port. Intake and exhaust valves are disposed for reciprocation in a direction lying perpendicular to the camshaft and simultaneously in a direction lying at an acute angle to a plane passing through the longitudinal axis of the cylinder and parallel to the axis of the camshaft. An intake cross-over manifold is cast integrally with the cylinder and is delimited by interior walls which are substantially straight in longitudinal direction from a fuel/air intake port to a point of intersection with the intake valve chamber.

Abstract: An oil cooler for small internal combustion engines is provided. The oil cooler comprises a heat exchanger mounted on the external surface of the engine crankcase, directly below the flywheel. The heat exchanger has an inner serpentine passageway in flow communication with the lubrication path of the engine oil. The heat exchanger further has a plurality of external fins, said fins being positioned directly below the flywheel. The flywheel includes a plurality of inlet apertures for drawing in cooling air to be blown over the heat exchanger.

Abstract: An intake manifold and cylinder head intake passageway for an air-cooled internal combustion engine. The manifold is substantially S-shaped and generally vertically oriented and communicates a carburetor having a horizonal bore with an overhead valve cylinder head having a horizontal intake passageway located at an elevation above that of the carburetor. The manifold has a turbulence inducing ridge at the entrance from the carburetor and the cylinder head intake passageway has a similar ridge at the entrance from the manifold. Each elbow bend in the manifold and in the cylinder head passageway is provided with a flat area at the outside curve of the bend which prevents puddling of fuel in the arcuate section of the bend and which causes any fuel which collects there to be spread out in a thin film which is then reintroduced into the air stream by a wedge-shaped ridge transverse to the flat area and rising therefrom to a ridge peak.

Abstract: The present invention is a self-lubricating bearing for a vertical shaft engine. A stub disposed within the journal bearing has a downwardly facing pocket which propels oil upward by centrifugal force during rotation of the shaft. The upwardly forced oil serves to lubricate the bearing above the stub. The lubrication system can be employed in both stub shaft and through shaft bearings.

Abstract: The present invention is a lubrication system for an internal combustion engine. lubricating oil flows through a central bore of a camshaft, and the camshaft sprays oil into a journal bearing. The crankshaft and camshaft are configured so that they are in phase, whenever the camshaft is closest to the camshaft during a rotation, the camshaft sprays oil into the journal bearing. Since the crankshaft has twice the rotational velocity of the camshaft, two spray holes are provided in the camshaft so that a spray hole supplies oil on each cycle of the crankshaft rotation.

Abstract: A lubrication system for the valve actuating mechanism of an internal combustion engine having a vertical drive shaft and horizontally oriented cylinder includes a rocker box housing the valve actuating mechanism with the valve actuating mechanism including a lower rocker arm and an upper rocker arm each oriented for rocking in a substantially horizontal rocking plane. A push rod cavity communicates at one end with the crankcase and at the other end with the rocker box. A cam shaft gear disposed at a lower end of a vertical cam shaft slings liquid oil from the crankcase through the push rod cavity into the rocker box. A dam is provided for retaining liquid oil in the rocker box at a level which partially submerges the lower rocker arm such that the rocking motion of the lower rocker arm splashes dammed oil to lubricate the valve actuating mechanism.

Abstract: An adjustable valve lash train for an overhead valve engine includes a rocker arm stud having a threaded shank received in a correspondingly threaded bore in said cylinder head. The rocker arm stud includes an integral head having a spherically shaped bearing surface on the undersurface thereof in engagement with a correspondingly shaped bearing surface on the rocker arm. The head of the rocker arm stud includes a hexagonally shaped recess in the top surface thereof for receipt of an adjustment tool. A threaded jam nut is received about the threaded shank of the rocker arm stud for selectively locking the threaded shank against rotation with respect to the threaded bore of the cylinder head. A push rod guide plate is sandwiched between the cylinder head and the jam nut adjacent the shank of the rocker arm stud for controlling lateral displacement of a push rod.

Abstract: A system for quickly stopping the internal combustion engine of a powered implement having a deadman control normally biased toward a first position and actuable by the implement operator to a second position for normal implement operation and optionally to a third position for actuating an engine starting mechanism. The engine has a flywheel coupled thereto for rotation with the engine crankshaft and that flywheel is provided with an annular friction surface of generally cylindrical configuration disposed coaxial with the axis of rotation of the flywheel. A braking member having a second friction surface is normally biased into engagement with the flywheel friction surface and coupled to a deadman control so that the two friction surfaces will be disengaged upon movement of the deadman control to a second or operational position by the implement operator.

Abstract: A combination counterbalancing and oil slinger mechanism located in the sump of a horizontal shaft internal combustion engine having two slinger counterweights radially connected on a slinger shaft. As the counterbalancing oil slinger rotates, it both counterbalances the inertial forces created by the moving parts of the engine and also lubricates the same moving parts by throwing lubricating fluid towards them. A deflector situated partially above the counterbalancing oil slinger directs the lubricating fluid towards the critical bearing points of the moving parts. A restricting wall in the engine sump controls the quantity of lubricating fluid flowing into the oil slinger well.

Abstract: A stamped exhaust manifold for a small internal combustion engine having a stamped sheet metal housing including an inlet and an outlet. A sheet metal baffle is located in the housing opposite the inlet and spaced from the housing to form a dead air insulating pocket between the baffle and the housing. The baffle is positioned so that hot exhaust gas entering the manifold from the engine through the inlet port will impinge directly on the baffle and will be deflected thereby through substantially 90.degree. to the manifold outlet port.

Abstract: An internal combustion engine is provided with a lubricating system and a full flow oil filtering circuit arranged in parallel with the main oil lubricating circuit of the engine. The lubricating system includes drive means an oil lubricating circuit for lubricating the drive means, an oil sump connected in flow communication with the lubricating system and an oil pump connected in flow communication with the sump and a lubricating system and operably driven by the drive means for pumping oil from the sump through the lubricating circuit and back to the sump. The parallel flow oil filtering circuit includes an oil filter disposed adjacent the oil sump and connected in flow communication therewith. An oil pump is disposed adjacent the sump and connected in flow communication with the sump and the oil filtering means. The oil pump is driven by engagement with the governor gear.

Abstract: An internal combustion engine is provided with a lubricating system and a full flow oil filtering circuit arranged in parallel with the main oil lubricating circuit of the engine. The lubricating system includes drive means an oil lubricating circuit for lubricating the drive means, an oil sump connected in flow communication with the lubricating system and an oil pump connected in flow communication with the sump and a lubricating system and operably driven by the drive means for pumping oil from the sump through the lubricating circuit and back to the sump. The parallel flow oil filtering circuit includes an oil filter disposed adjacent the oil sump and connected in flow communication therewith. An oil pump is disposed adjacent the sump and connected in flow communication with the sump and the oil filtering means. The oil pump is driven by engagement with the governor gear.

Abstract: In an internal combustion engine a breather induced valve lifter mechanism lubricating system wherein oil mist is conducted from the crankcase through one push rod tube to the rocker box. The oil mist is caused to flow around the valve actuating mechanism by a baffle before flowing out of the rocker box through a second push rod tube to the breather chamber. Oil which condenses in the rocker box flows through the second push rod tube to the breather chamber. Oil which collects in the breather chamber will be caused to flow through a drainage passage from the breather chamber to the oil sump in the crankcase.

Abstract: A system for quickly stopping the internal combustion engine of a powered implement having a deadman control normally biased toward a first position and actuable by the implement operator to a second position and having an operator actuable engine starting mechanism is disclosed. The engine has a flywheel coupled thereto for rotation with the engine crankshaft and that flywheel is provided with an annular friction surface disposed generally in a plane normal to the axis of rotation of the flywheel. A braking member having a second friction surface is normally biased into engagement with the annular friction surface of the flywheel and coupled to the deadman control so that the two friction surfaces will be disengaged upon movement of the deadman control to a second or operational position by the implement operator.