Mach probe measurements of bias-induced ion flows were made in the Interchangeable Module Stellarator (IMS) as a function of neutral pressure and viscosity (which increases with minor radius) and compared to a fluid theory model. Using a probe model for an unmagnetized plasma, the poloidal flow speed measured with a Mach probe agrees with that calculated from momentum balance to within 15%. The dependencies of the measured ion flow magnitudes and decay rates on neutral pressure and viscosity as predicted by the theory are qualitatively observed in the experimental measurements, clearly demonstrating the effects of both ion-neutral collisions and viscosity in the damping of the bias-induced flows. However, the measured flow direction is nearly poloidal, while the theory predicts a predominantly Pfirsch-Schlüter-like toroidal flow. Also, the two-dimensional variation at a constant toroidal angle of the parallel electron current was measured in an unbiased plasma. The measured profiles demonstrate the dependence of the current on both the radial pressure gradient and the cosine of the poloidal angle, as predicted by theory.