Cartridge filter assembly with hand primer

A fuel filter assembly (22) employs a hand primer (10) and a disposable filter cartridge (18) mounted to a header (14). The filter cartridge (18) has a filter element (36) which defines an interior chamber (42) for receiving the filtered fuel. The hand primer includes a diaphragm (48) which cooperates with the header to define a reservoir (46) and a valve plate (66) having a plurality of orifices and an axial opening for providing fluid communication between an exit passage of the header and the reservoir (46) and between the chamber (42) and the reservoir (46), respectively. A first check valve (118) is mounted in the opening and a second check valve (140) is mounted in an axial bore in the first check valve. The first and second check valves (118, 140) are moveable between an open position for allowing flow through the orifices of the valve plate (66) and orifices in the first check valve (118), respectively, and a closed position for preventing such flow. The filter assembly (22) is primed by pushing the diaphragm (48) downwards, creating a high pressure which moves the first check valve (118) to the open position and the second check valve (140) to the closed position, causing trapped air to be expelled through the orifices and the exit passage. Removing the downwards force allows a spring (64) to return to bias the diaphragm (48) upwards, creating a low pressure which moves the first check valve (118) to the closed position and the second check valve (140) to the open position, and drawing fuel from the interior chamber (42).