Abstract: Disclosed herein is an internal combustion engine comprising a crankcase, a cylinder extending from the crankcase and having an inlet port, a piston located in the cylinder, a transfer passage located between the crankcase and the cylinder inlet port, a fuel pump adapted to communicate with a source of fuel for normal operation, a carburetor having an air induction passage communicating with the crankcase and including a venturi, which carburetor also includes a float bowl communicating with the fuel pump and a high speed nozzle communicating between the float bowl and the venturi, a low speed fuel nozzle communicating with the transfer passage adjacent the inlet port, and a fuel line communicating between the float bowl and the low speed nozzle and including therein check valve means preventing flow from the transfer passage to the float bowl and permitting flow from the float bowl to the transfer passage, which fuel line also includes fuel flow metering means.

Abstract: Disclosed herein is an internal combustion engine comprising a crankcase, a cylinder extending from the crankcase and having an inlet port, a piston located in the cylinder, a transfer passage located between the crankcase and the cylinder inlet port, a fuel pump adapted to communicate with a source of fuel for normal operation, a carburetor having an air induction passage communicating with the crankcase and including a venturi, which carburetor also includes a float bowl communicating with the fuel pump and a high speed nozzle communicating between the float bowl and the venturi, a low speed fuel nozzle communicating with the transfer passage adjacent the inlet port, and a fuel line communicating between the float bowl and the low speed nozzle and including therein check valve means preventing flow from the transfer passage to the float bowl and permitting flow from the float bowl to the transfer passage, which fuel line also includes fuel flow metering means.