Description
The outside of the filter is a metal can with a sealing gasket, which can make it close to the mating surface of the engine. The bottom plate of the jar fixes the gasket and punches holes around the inner area of the gasket. The center hole is threaded to mate with the oil filter assembly on the engine block. Inside the water tank is the filter material, most commonly made of synthetic fibers. The oil pump of the engine delivers the oil directly to the filter and enters the filter through the holes on the periphery of the bottom plate. Dirty oil passes (pushed under pressure) through the filter medium and returns through the center hole, where it re-enters the engine.