A seal assembly is for sealing a space between a housing and a shaft rotatable about a central axis. The seal assembly includes a seal body connectable with the housing and having an inner circumferential sealing surface. The sealing surface has opposing axial ends and is slidably contactable with the shaft outer surface to define a sealing interface. An annular biasing member, preferably a garter spring, is disposed about a portion of the seal body and has a centerline. The biasing member exerts a biasing force directed radially inwardly toward the centerline, such that the seal exerts a contact pressure on the shaft. Further, the biasing member is angularly positioned on the seal body such that the contact pressure extends axially along the shaft axis to direct substances entering the sealing interface toward a proximal axial end of the sealing surface when the shaft rotates about the central axis.