Abstract: A starting system for an internal combustion engine is provided for enhancing engine startability and performance by simultaneously controlling the volume of air flowing through a carburetor and the ratio of an air/fuel mixture through a single manual operation. The starting system is constructed to utilize atmospheric air control feed back to a carburetor and includes a piston disposed with a chamber which accesses two atmospheric ports. When the piston is positioned to fully close a first of the ports, a second of the ports is fully open. Similarly, when the piston fully opens the second port, the first port is fully closed. The two atmospheric ports access the carburetor idle system and intake manifold of the engine respectively. For starting of the engine in cold temperatures, the starting system also includes a fuel prime arrangement for enriching the ratio of air/fuel delivered to the engine.

Abstract: A diaphragm-type carburetor has a high speed adjusting needle and a low speed/idle adjusting needle which are independently supplied with fuel from the metering chamber. The path for fuel to the low speed/idle needle has a valve which is controlled by the angular position of the throttle shaft such that when the throttle shutter is closed the valve is open whereas when the throttle shutter is open the valve is closed.

Abstract: A fuel supply system for supplying fuel from a fuel source to an internal combustion engine includes a valve assembly having a shut-off valve automatically responsive to negative pressures transmitted from an engine. The shutoff valve is diaphragm responsive and moves in the same direction as the flow of fuel in order close the valve assembly, thereby retaining the content of a fuel receptacle infinitely. The shutoff valve is adapted to withstand pressures which may develop in a fuel receptacle without opening.

Abstract: A fuel supply system for supplying fuel from a fuel source to an internal combustion engine includes a valve assembly having a shut-off valve automatically responsive to negative pressures transmitted from an engine. The shutoff valve is diaphragm responsive and moves in the same direction as the flow of fuel in order close the valve assembly, thereby retaining the content of a fuel receptacle infinitely. The shutoff valve is adapted to withstand pressures which may develop in a fuel receptacle without opening.

Abstract: A fuel supply system for supplying fuel from a fuel source to an internal combustion engine includes a valve assembly having a shut-off valve automatically responsive to negative pressures transmitted from engine aspiration or a fuel pump. The shutoff valve is diaphragm responsive and moves in the same direction as the flow of fuel in order close the valve assembly, thereby retaining the content of a fuel receptacle infinitely. The shutoff valve is adapted to withstand pressures which may develop in a fuel receptacle without opening. In one embodiment, the fuel supply system includes a vapor line for directing fuel vapor from the fuel receptacle to a portion of the engine, where it can be combusted. The vapor line is operatively associated with a fuel cap. The fuel cap can be selectively rotated positioned so as to permit fuel vapor to enter the vapor line.

Abstract: An automatic choke assembly or starting aid is coupled with a small internal combustion engine. The choke assembly is responsive to a pressure differential in the internal combustion engine which causes movement of a mechanism to control the amount of combustion air entering into the internal combustion engine. The mechanism provides sufficient combustion air during start-up and during continuous running condition of the internal combustion engine.

Abstract: An automatic choke assembly or starting aid is coupled with small internal combustion engines. The choke assembly is responsive to pressure differentials in the internal combustion engine which causes movement of a mechanism to control the amount of combustion air entering into the internal combustion engine. The mechanism provides sufficient combustion air during start-up and during continuous operation of the internal combustion engine.

Abstract: A carburetor comprising a main body portion defining a carburetor mixing passage having an air intake side and an engine outlet side, a fuel pump, a throttle shutter mounted within the carburetor mixing passage between the air intake side and the engine outlet side. The carburetor has a metering chamber for supplying fuel from the fuel pump into the carburetor mixing passage via a main discharge port, the main discharge port opens into the carburetor mixing passage on the air intake side of the throttle shutter. A starting fuel supply passage extends from the pressure side of the fuel pump to the carburetor mixing passage. A means is provided for selectively opening and closing the starting fuel supply passage such that when the throttle is in a partially opened position and the starting fuel supply passage is open, the fuel pump causes fuel to be injected through the starting fuel supply passage into the carburetor mixing passage.

Abstract: A vapor return primer for priming and regulating pressure in a carburetor is disclosed. The vapor return primer includes a housing having an inlet and an outlet. The inlet is coupled with the high pressure side of the carburetor. The outlet is coupled with a fuel tank. A resilient flexible membrane is coupled with the housing for moving fluid through the inlet and outlet to prime the carburetor. A pressure relief mechanism is coupled with the housing to provide one-way flow from the housing through the outlet to the fuel tank during priming. Also, the pressure refief mechanism regulates the carburetor pressure when the internal combustion engine is in a continuous running mode.

Abstract: A fuel primer for small internal combustion engines is disclosed. The fuel primer is associated with a metering chamber of a carburetor. The metering chamber includes an inlet port and an outlet port and communicates with both a fuel source and a venturi on the carburetor by conventional means. The primer includes a mechanism which communicates with the restricted inlet port to provide one way flow into the metering chamber. A second mechanism communicates with the unrestricted outlet port to provide one way flow from the metering chamber. A third mechanism associates the first and second one way mechanisms for pressurizing and depressurizing the flow through the primer so that fuel is drawn into the metering chamber from the fuel source.

Abstract: A fuel primer for float type carburetors for small internal combustion engines is disclosed. The fuel primer is associated with the fuel bowl of a float type carburetor. The fuel bowl is coupled with a fuel inlet, an atmospheric outlet vent, and a nozzle. The fuel inlet is coupled with the fuel source and the nozzle is coupled with the carburetor venturi. The primer includes a mechanism coupled with the outlet vent for introducing a pressurized flow into the fuel bowl. The pressurized flow introduces fuel from the fuel bowl into the carburetor venturi, which, in turn, enables fuel to pass into the combustion chamber of the internal combustion engine.

Abstract: A choke assembly or starting aid for small internal combustion engines is disclosed. An inertia valve is resiliently biased in the bore of the engine. The inertia valve is responsive to vibration of the internal combustion engine for providing a controlled amount of combustion air into the carburetor of the internal combustion engine.

Abstract: A fuel primer for small internal combustion engines is disclosed. The fuel primer is associated with a metering chamber of a carburetor. The metering chamber includes an inlet port and an outlet port and communicates with both a fuel source and a venturi on the carburetor by conventional means. The primer includes a mechanism which communicates with the restricted inlet port to provide one way flow into the metering chamber. A second mechanism communicates with the unrestricted outlet port to provide one way flow from the metering chamber. A third mechanism associates the first and second one way mechanisms for pressurizing and depressurizing the flow through the primer so that fuel is drawn into the metering chamber from the fuel source.