Abstract: A fuel delivery system for an internal combustion engine. The fuel delivery system includes a carburetor housing having an air passage with a throttle valve disposed therein. A choke lever is movably mounted to the carburetor housing for restricting air flow into the air passage. A fuel injection device is provided for injecting fuel into the air passage before the engine is started. Movement of the choke lever to an engaged position simultaneously opens the throttle valve, restricts air flow into the air passage and activates the fuel injection device to inject a predetermined volume of fuel into the air passage. The air-flow restriction and the predetermined volume of fuel are adjusted to compensate for changes in ambient temperature.

Abstract: A fuel delivery system for an internal combustion engine. The fuel delivery system includes a carburetor housing having an air passage with a throttle valve disposed therein. The air passage has an inlet and an outlet. The outlet is in communication with the engine. Means are provided for simultaneously opening the throttle valve, restricting air flow into the air passage and injecting a predetermined volume of fuel into the air passage before the engine is started. Other means are provided for automatically adjusting the restriction of air flow and the predetermined volume of fuel to compensate for changes in ambient temperature.

Abstract: A flexible line trimmer is powered by a two-stroke internal combustion engine. The engine is scavenged in a uniflow fashion and has a scavenging cylinder and an exhaust cylinder connected by a common combustion chamber. Each cylinder has a piston turning one of two cantilevered crankshafts that are geared through adjacent counterweights having integrally formed teeth. The crankshafts extend in opposite directions for self-balancing. One crankshaft is coupled to a flywheel fan and other coupled to a starter. A fuel and air mixture is transferred to a common crankcase for the crankshafts through an intake port located on the exhaust cylinder. The piston of the scavenge cylinder is retarded with respect to the exhaust cylinder. An exhaust window opens prior to a scavenge window. The scavenge window closes after the exhaust window. The exhaust window is shortened to improve crankcase compression. The cylinders are joined in a siamese fashion, fabricated from a single piece, and skewed toward each other.

Abstract: A portable, hand-held blower/vacuum unit has a housing structure defined by an upper engine shroud removably connected to the top wall of a lower impeller housing. Disposed within the shroud is a small internal combustion engine having a vertical crankshaft which extends downwardly through a depending well section formed on the top wall of the impeller housing, the lower shaft end being drivingly connected to a centrifugal fan impeller positioned within the impeller housing and operative to force a flow of ambient air therethrough. The engine is resiliently and floatingly mounted within the shroud by a resilient support system which prevents rigid contact between the engine and the shroud or the impeller housing to thereby substantially reduce engine vibration transmitted to the housing structure, and permit deflection of the engine relative to the housing structure to lessen the possibility of engine damage caused by impeller impact from ingested objects.