Pump makes a loud grinding or screeching noise while running.

Safety: Turn off power before inspecting the motor.

• Isolate noise source: Use a mechanic's stethoscope or a long screwdriver to listen near the motor vs. the wet end to confirm the noise is from the motor bearings.
• Check for leaks: Inspect for water leaks at the mechanical seal that may have entered the motor.
• Short-term operation: The pump can sometimes run for a short period with noisy bearings, but failure is imminent and can lead to motor seizure.
• Plan replacement: Schedule replacement of the motor assembly or have a motor shop replace the bearings if economical.

Operating with failing bearings can cause further damage; prompt repair is recommended.