Loud rattling or grinding noise from the base when the motor is running.

Safety first: Unplug the cleaner before inspection.

• Isolate source: Run the unit briefly (if safe) and listen to determine whether the noise is from the brush area or motor area.
• Brush area: Remove the brush cover and check for stones or hard objects in the brush housing or gearbox. Tighten any loose screws.
• Motor area: Open the motor housing and inspect the plastic fan for broken blades. Replace the motor fan or entire motor assembly if damaged.
• Bearings: If the motor shaft has excessive play or squeals, the bearings are worn and the motor should be replaced.