Abstract: A supplementary fuel system adds propane to the induction passage of an ethanol fueled engine to start and sustain operation of the engine at low temperatures. The propane flow is cycled on and off during cranking of the engine and the propane delivery pressure is varied with induction passage pressure.

Abstract: An air cleaner for use on internal combustion engines is provided with a bellows valve which is located on the clean side of the filter and blocks the outlet to the carburetor when the engine is not operating to prevent fuel vapor escape and is aspirated by a source of vacuum during engine operation to retract to an open position permitting free filtered air flow to the carburetor.

Abstract: In a fuel vapor recovery system for an internal combustion engine, a proportional fuel vapor purge flow control apparatus is used to regulate the flow of a fuel vapor-air mixture to the induction system of the engine, the flow control apparatus including a variable area flow control valve which is diaphragm operated by exhaust back pressure to provide a canister purge flow area which is proportional to exhaust back pressure and a vacuum regulator operative to provide a constant pressure differential across the variable area valve.

Abstract: A method of capturing the fuel vapors during the fueling of vehicles on a vehicle assembly line using fuel vapor adsorbing devices destined for usage in the evaporative emission control systems of vehicles on that assembly line.

Abstract: A thermostatically responsive valve for controlling fluid, including a thermally responsive power member for operating the valve and indicator means movable to an operative position indicative of an overheat condition in response to high fluid temperatures. Latch means are provided to prevent movement of the indicator means into the overheat position during an overheat condition when activated by the thermally responsive power member, so that the responsibility of the thermostat can be determined by examination.

Abstract: A vapor regulating valve for use in a system for mixing air with fuel vapor from a fuel tank is constructed so that fuel vapor pressure against a diaphragm actuates a valve to allow engine induction vacuum to be exerted against another diaphragm to actuate a metering valve to accurately mix air and fuel vapor for delivery to the engine intake manifold. The full on-and-off action of the metering valve ensures a consistantly accurate air fuel ratio; and the use of the diaphragms themselves as the moving valve elements results in less expense and greater reliability.