Make sure it is fully assembled correctly. Way easier in the Z2 than the original but if the raceway is blocking the way any pressure will cause the Z2 to stop spinning because it thinks that there is a ball stack. Also you can run diagnostics on it *check your manual*. Try those things and come back if problems ensue.
G.I. Sportz, DLX Technologies, Raza Design
Diamond Hill Paintball Park and Shocker Paintball