Crankcase ventilation inside-out flow rotating coalescer

A method for reducing crankcase pressure in an internal combustion engine crankcase generating blowby gas, the method comprising:

• providing a crankcase ventilation system including a coalescing filter element separating air from oil in said blowby gas;
• providing said coalescing filter element as an annular gas permeable fibrous filter media element having a hollow interior, the coalescing filter element including an axial end cap that engages an inlet port;
• supplying said blowby gas to said hollow interior while rotating said coalescing filter element to pump said blowby gas out of said crankcase and into said hollow interior due to centrifugal force caused by rotation of said coalescing filter element forcing said blowby gas to flow radially outwardly through said filter media element, said pumping effecting reduced pressure in said crankcase.

An internal combustion engine crankcase ventilation rotating coalescer separating air from oil in blowby gas from said crankcase, comprising a coalescing filter assembly comprising an annular rotating coalescing filter element comprising a gas permeable fibrous filter media through which said blowby gas is passed so as to cause coalescence of oil on said filter media, the filter media having an inner periphery defining a hollow interior, and an outer periphery defining an exterior, an inlet port supplying said blowby gas from said crankcase to said hollow interior, and an outlet port delivering cleaned separated air from said exterior, further comprising an axial end cap on said annular rotating coalescing filter element, wherein said axial end cap is substantially sealed to said inlet port such that in at least one operating condition, little or no blowby gas bypasses said annular rotating coalescing filter element.