A rotating system includes a drive member and a driven member. The rotating system includes a coupling positioned to rotatably couple the drive member to the driven member and a housing surrounding a portion of the coupling to define an inside and an outside, the housing having a plurality of apertures. A fan is coupled to the coupling and operable to produce a flow of air from the inside to the outside via at least one of the plurality of apertures, and a guide tube is positioned within one of the plurality of apertures to guide a flow of air from the outside to the inside.