An axial face seal assembly including a seal member which is seated in a carrier, the carrier being non-rotatably connected to a base member but movable axially thereto and biased from the base member by means of a compression spring interposed between the base member and the carrier, the base member being axially and non-rotatably securable to a drive shaft by means of an open ring clamp having first end second ends. The ring clamp is supported on the base member, at least one of said first and second ends being movable relative to the other end in a circumferential direction; and wherein tightening means is rotatably journalled on the base member for adjusting the relative distance between the first and second ends of the ring clamp. A mounting fixture is likewise disclosed and cooperating with the seal assembly in a mounting procedure.