Abstract: An oil filtering and purifying apparatus comprising a closed pressure tank with fluid inlet and outlet openings and a plurality of vertically stacked filter units removably arranged within the tank; the filter units have central hubs with vertical flow passages; the flow passages of adjacent hubs communicate with each other and with the outlet opening; each unit includes a lower horizontal plate carried by its hub, a felting screen supported in spaced relationship above the plate and cooperating therewith to define a fluid conducting chamber below the screen and about the hub; and fluid ports in the hub communicating with the flow passage therein and with the chamber related thereto; the apparatus next includes a deposit of particulate filtering material atop the felting screen of each unit; a section line from said inlet opening to a supply of oil to be filtered; and a motor driven fluid pump with its inlet communicating with said outlet opening and its outlet communicating with an oil delivery line.