Abstract: A bearing system includes a bearing housing configured to house a bearing and enclosing a free volume for receiving a lubricant, a bearing, a pump configured to pump lubricant into the free volume, a shaft in an opening in the housing rotatably supported by the bearing, an exclusion seal between the shaft opening and the shaft that is repeatably and non-destructively shiftable from a sealing state in which it substantially prevents lubricant from leaving the free volume and a release state in which it allows lubricant to escape between the exclusion seal and the shaft. The exclusion seal is caused to shift by increasing and decreasing a pressure in the bearing housing, and the system includes a controller configured to repeatedly shift the exclusion seal by raising and lowering the pressure in the free volume to continuously maintain a lubricating film between the exclusion seal and the shaft.