A new disk-type viscous pump, with radial pumping grooves on its stator, is described and its performance analyzed. Its flow rate and discharge pressure relationship is found to be linear. Two proposed viscous pumps of this new design having slightly different dimensions are considered and compared to the recently reported design utilizing multilobes. Analyses on these two proposed pumps show that this new design exhibits higher flow rate characteristics than the recent multilobe design for the same pump size and rotor–stator clearances.