Method and apparatus for applying a protective coating to the surfaces of air vents in a vented brake rotor wherein the method includes the steps of rotating the rotor, directing coating material along with a stream of air toward the inlets of the vents to flood the vents with coating material to coat the surfaces, applying a suction to the outlets of the vents to remove and recover the excess material, and curing the coating. The apparatus includes fixtures for mounting the rotors that are driven to rotate the rotors during the coating operation, and for automatic operation a conveyer for advancing the rotors through a vent coating station, an exterior coating station for coating exterior rotor surfaces, and a curing station.