What indicates a worn bearing in a motor?

A large amount of movement in any direction of the shaft is a key indicator of worn bearings in a motor. When bearings wear out, they lose their ability to maintain the shaft in a stable position. This wear and degradation lead to excessive play or movement of the shaft, which can be felt through physical inspection or observed in the operational behavior of the motor.

This movement compromises the alignment and balance of the system, which can lead to further operational issues and potential damage over time. Therefore, the shaft should ideally have very minimal movement; significant play suggests that the bearings are failing and need to be replaced to restore proper function and prevent further deterioration.

In contrast, while constant humming noises, overheating, and vibrations during startup can indicate other issues within a motor, they are not primarily diagnostic indicators of worn bearings.