Abstract: A method of valving a flow of pumped fluid, to prevent siphoning of the flow when the pump is stopped, including the steps of filling a chamber with fluid, directing a small flow of pumped fluid into the chamber to increase its volume, opening a main flow valve by the increase in chamber volume, providing a leak in the chamber to reduce the volume of fluid therein when the small flow of pumped fluid is terminated, and closing the main flow valve by the decrease in chamber volume.

Abstract: A liquid fuel shut-off valve for insertion through the feed pipe opening and mounting inside a fuel tank including, in combination, a valve body having an inlet and an outlet joined by a first bore aligned axially with the feed pipe through which the fuel is fed to fill the tank, a valve spool rotatably mounted in a cross-bore formed in the valve body between the inlet and the outlet and attached to a float extending outward from the valve body that is responsive to the level of liquid in the tank, and a valve shut-off formed in the spool including a second bore formed transverse thereto for passing fuel between the inlet and the outlet, and a relief opening formed in the trailing edge of the wall of the second bore allowing progressive rotation of the second bore from a first position in full hydraulic alignment with the first bore to a second position in full hydraulic closure with the first bore free of a countervailing hydraulic turning moment developed by the flow of fuel there through.

Abstract: An add-on liquid overflow shut-off valve including a valve body, a float and an arm connecting the float to the body that is insertable in fully assembled form through a standard tank lid opening, and further including a flanged end on the valve body for engagement outside and above the rim of the opening and threads associated therewith to engage the periphery of the opening to anchor the body inside the interior of the tank and at the top thereof, pneumatic openings formed in the top flanged end in spaced-apart relation for connection respectively to a pressurized pneumatic source and a pneumatic-driven liquid pump arranged to pump liquid into the tank through another opening in the tank, first and second pneumatic passageways formed interior the body extending from the openings, a third pneumatic passageway formed in the body for interconnecting the first and second passageways, and a shaft pivotally received in the body, having a fourth pneumatic passageway formed therethrough for pneumatic alignment with