The filter removes volatile, particulate and water-based contaminants from a fluid, such as lubricating oil, of a different density than the contaminants. The device has a cone shaped, jet-propelled, helical-spiral wiper rotor creating centrifugal forces that separate the volatile and heavier particulate matter. Ports in a base assembly facilitate removal of the separated contaminants. A settling tank with vertical grid filter minimizes turbulence for further separation of heavier particulate matter. A volatile tank with vertical grid filter and flow restrictor minimizes turbulence to allow volatiles to rise from the fluid. A filter tank filters out remaining particulate matter from the fluid. A combination of flow restrictors and baffles minimize cross-contamination, thereby maximizing purity of oil returned to the engine. The collection tanks are easily cleaned and reused. The compact design minimizes oil volume necessary for purification. Aluminum housing and by-pass design maximize engine oil cooling to enhance viscosity maintenance.