During an inspection, if bearings on a centrifugal pump are excessively hot, what is a likely cause?

Excessively hot bearings on a centrifugal pump are commonly attributed to improper lubrication. Bearings require an appropriate amount of lubricant to reduce friction and facilitate smooth operation. If the lubrication is inadequate or inappropriate, it can lead to increased friction and heat generation, resulting in bearings overheating. Proper lubrication also helps in dissipating heat, but when it’s lacking, the bearings can wear out more rapidly, leading to larger operational issues and potential failure of the pump system.

The other options can affect the performance of the pump and may contribute to other forms of wear or inefficiency, but they do not specifically relate to the heat observed in the bearings as directly or significantly as lubrication does.