Abstract: A fuel filter with a pressure regulating valve for fuel circulated from a fuel tank and injected into an internal combustion engine. The fuel filter comprises a filter pot closed by a cover and an annular filter element for radially filtering flow from the outside in. Fuel flows in and out through main flow connections on opposite sides of the filter. There is a recirculation connection to recirculate fuel. There is a pressure regulating valve on one end of the filter housing with the discharge connection. The pressure regulating valve operates against atmospheric pressure and has a spring-loaded diaphragm which acts in conjunction with a closure ram to close the inlet port of a recirculation flow duct which passes through the center of the filter and connects the regulating valve to the return connection. The diaphragm is fastened with the valve seat in a sealed manner to the edge of the pressure regulator housing, which open into the filter port and is formed in the cover of the filter housing.

Abstract: A fuel feed pump arrangement which includes a housing serving for accommodating both an electric motor and a feed pump system coupled to the electric motor. A diaphragm is provided in the housing with the diaphragm maintaining a system pressure for a predetermined period of time after the drive motor of the pump system has been turned off.

Abstract: An internal combustion engine with a return line for exhaust gases which connects the exhaust system with an inlet line provided with a throttle valve; the orifice of the return line in the inlet line is thereby located within the control cross section of the inlet line so that with a closed and substantially closed throttle valve, the orifice is upstream of the throttle valve whereas with an opened or substantially opened throttle valve, it is disposed downstream thereof.