Abstract: A liquid filter includes an annular filter cartridge and a combination anti-drain back and relief valve assembly. The combination valve includes a valve seat from which axially extending arms extend and a spring retainer and spring which holds a gasket against the valve seat. The gasket includes an anti-drainback portion which projects from the valve seat and a relief valve portion which is supported on the valve seat. Upon assembly the combination valve and filter element in the housing, the filter assembly is supported by the spring retainer and is forced into sealing engagement with the gasket, holding the latter against the valve seat in a gasket engaging area between the relief valve portion and the anti-drainback portion. This assembly process also removes the coil spring load from the barbs on the valve seat arms.

Abstract: A liquid filter for filtering the lubricating oil of an internal combustion engine includes a bypass passage permitting liquid to flow from the outlet to the inlet in a direction opposite to normal flow through the filter when the engine is initially filled with oil by a pressure lubrication fill process. When the engine is first started, a valve responds to normal engine oil pressure to close the bypass passage.