Abstract: A viscous pumping system for lubricating a bearing, including a reservoir configured to store a lubricant, a housing connected to the reservoir and mounting the bearing, and a shaft disposed in the housing and supported by the bearing. The shaft is rotatable in a forward direction and a reverse direction and has a first helical groove and a second helical groove. The first helical groove and the second helical groove are configured so that they act to pump sufficient lubricant from a groove origin to the bearing when said shaft rotates in both the forward direction and the reverse direction. It is contemplated that the viscous pumping system may be used to lubricate the bearing of a variable capacity compressor.