An end cap of a filter element has canted fins in an annular space between
a filter element and filter housing for imparting a rotary motion to a
fluid prior to the fluid passing through the filter element. The end cap
includes a plurality of axially extending legs upstream of the fins, which
legs engage a nutplate. Spaces between the legs provide an inlet allowing
dirty fluid to flow to the outside surfaces of the filter element. The
fins remove large particles from the fluid by centrifugal force so that
large particles do not add to the contaminant load in the filter elements.
