Abstract: An internal combustion engine including a camshaft journalled in a bearing for rotational movement therein. The camshaft includes a main oil passageway extending axially therethrough and is in flow communication with the oil sump. The camshaft further includes an auxiliary passageway extending from the main passageway to a sidewall outer surface of the camshaft. A first lubricating passageway is formed within the crankcase and extends from the camshaft bearing to the cylinder head, and a second lubricating passageway is formed within the cylinder head and extends from the first passageway to the upper portion of the valve rocker mechanism of the engine. As the camshaft rotates upon engine operation, the auxiliary passageway in the camshaft is in periodic flow communication with the first passageway to provide a pulsed flow of oil to the first passageway. The oil then flows through the second passageway and lubricates the valve rocker mechanism.

Abstract: A safety device for a single cylinder internal combustion engine powered implement includes a solid state ignition circuit for producing a spark in a spark plug. The ignition circuit includes a first coil for generating a normally timed sparking voltage in the circuit for normal engine operation, and a second coil for generating an advanced timed sparking voltage in the circuit for stopping the engine. The first and second coils are each disposed about the periphery of the flywheel and angularly displaced from each other. A deadman control having a first and second position, selectively decouples one of the coils from the ignition circuit depending on the state of position of the deadman control.

Abstract: A carburetor for an internal combustion engine is provided. The carburetor float bowl is internally vented through a venting path that leads from the carburetor throat, via the primer chamber, to the airspace above the float bowl. An annular lip is provided on the primer bulb that acts as a check valve and seals off the venting passageway when the primer bulb is depressed, thereby insuring that the primer charge passes into the float bowl and is not lost through the venting passageway.

Abstract: An internal combustion engine having a flywheel attached to the crankshaft externally of the crankcase. A permanent magnet is affixed to the flywheel proximate the periphery thereof and has a flat exposed face toward the crankcase. The flywheel has fan blades attached thereto for generating a current of air which flows generally radially away from the flywheel and is directed across the engine cylinder by a blower housing. A solid state ignition module is attached to the crankcase axially spaced from the flywheel toward the crankcase so as to be situated substantially free of the air flow generated by the flywheel. The ignition module has a ferromagnetic core with legs extending parallel to the crankshaft and lying in a plane perpendicular to a radius of the crankshaft. The core legs each have a flat end face disposed parallel to the flat face of the permanent magnet, and are adjustable with respect thereto.

Abstract: An air-cooled engine having a vertical crankshaft and a horizontal cylinder. The cylinder is cast aluminum alloy and has the intake and exhaust valves located next to one another on one side of the cylinder, with the carburetor located on the other side of the cylinder. An intake cross-passageway integrally cast in part with the cylinder passes under the piston bore to connect the intake valve to the carburetor. For casting purposes, the lower side of the passageway is open in the cylinder casting to permit removal of the passageway casting core and forming an opening having side walls extending transverse to the piston bore extending from the passageway to the exterior of the cylinder. A cover having side walls corresponding to and lying adjacent the side walls of the opening is disposed in the opening. The cover has a curved inner surface corresponding to the curvature of the passageway.

Abstract: A single cylinder internal combustion engine has an inline counterbalance weight system which includes a counterbalance shaft rotatably mounted ot a crankcase and extending generally parallel to a crankshaft of the engine and transverse to and aligned with the rectilinear path of reciprocation of the piston pivotally connected to the crankshaft, and a counterbalance weight eccentrically mounted on the counterbalance shaft. The counterbalance shaft and weight are rotated in a direction opposite to the direction of rotation of the crankshaft. The crankshaft and the weights mounted thereon and the counterbalance weight are aligned with and disposed in symmetrical relationship to the rectilinear path of the piston.

Abstract: An improved engine construction is disclosed having a valve train including valves and corresponding valve stems for controlling the intake and exhaust ports, cams for imparting reciprocating motion to the valves by way of the valve train, and a valve spring for biasing each valve toward its closed position and the valve train into tracking relation with the cam. The only element of the valve train coupling a cam to a stem is a cam follower with a depression for receiving the corresponding stem end and a cam engaging surface opposite the depression with the cam follower being held captive intermediate the stem and cam solely by the spring biasing of the stem toward the cam and the engagement of the stem end and the depression.

Abstract: An improved engine construction is disclosed having a valve train including valves and corresponding valve stems for controlling the intake and exhaust ports, cams for imparting reciprocating motion to the valves by way of the valve train, and a valve spring for biasing each valve toward its closed position and the valve train into tracking relation with the cam. The only element of the valve train coupling a cam to a stem is a cam follower with a depression for receiving the corresponding stem end and a cam engaging surface opposite the depression with the cam follower being held captive intermediate the stem and cam solely by the spring biasing of the stem toward the cam and the engagement of the stem end and the depression. Another feature of the engine resides in the engine block casting which includes an exhaust gas passageway extending from an engine cylinder and including near the end thereof remote from the cylinder an enlarged cavity which defines at least a part of a muffler shell.

Abstract: An improved engine construction is disclosed having a valve train including valves and corresponding valve stems for controlling the intake and exhaust ports, cams for imparting reciprocating motion to the valves by way of the valve train, and a valve spring for biasing each valve toward its closed position and the valve train into tracking relation with the cam. The only element of the valve train coupling a cam to a stem is a cam follower with a depression for receiving the corresponding stem end and a cam engaging surface opposite the depression with the cam follower being held captive intermediate the stem and cam solely by the spring biasing of the stem toward the cam and the engagement of the stem end and the depression. The spring biasing is provided by a coiled wire spring having outwardly extending legs each of which engages a corresponding stem to urge the valves toward their closed position.