The Shaft is any rotating machine part used to transmit power from one part to another. The rotation of crankshafts then allow the clutch to engage the driven shaft, such as a spindle shaft which turns the mower blades. Shafts can commonly be damaged from improper installation, impact or collisions bending the shaft, or improper lubrication increasing wear due to friction and overheating. Make sure all shafts in machinery are working properly and maintained to ensure proper operation and safety.