Abstract: A two-stroke diesel or gas fueled multi-cylinder engine utilizes a re-circulating type constant pressure feed lubrication system and is equipped with a supercharger or turbocharger combination connected in series to assist in charging the cylinders with air and also assists in scavenging the exhaust gases. The piston head is domed to assist the flow of the scavenging air in an upward direction toward the inside of the cylinder, and to facilitate the flow of exhaust gases to atmosphere. The scavenging port and exhaust port openings are formed in the same plane through the walls of the cylinder above the bottom dead center position of the piston head. The lower side of the scavenging port opening inclines inwardly and upwardly toward the cylinder wall so that the flow of scavenging air creates a turbulent action as it enters inside the cylinder for efficient scavenging of the exhaust gases.

Abstract: A two-stroke engine includes an intake-and-scavenge valve in the cylinder head together with a gasoline fuel injection system, a recirculating type constant pressure lubricating system, and a blower or turbo charger combination assisting in charging the cylinder with air and also assisting in scavenging the exhaust gases. The piston head is domed with one side curving downwardly towards the exhaust port formed through the wall of the cylinder above the bottom dead center position of the piston head. The exhaust port slopes outwardly and downwardly following generally the slope of the piston to facilitate the flow of exhaust gases therethrough assisted by the scavenging air entering through the inlet-and-scavenger valves. The valve is operated by a cam mounted on a camshaft upon the cylinder head which in turn is operatively connected to the crankshaft. The shape of the cam lobe is such that it controls the opening, closing and duration of opening of the valve with the valve being opened approximately 153.