Florida Wastewater Practice Test

What could be the cause of excessively hot bearings on a pump?

1. Under lubrication

2. Aging components

3. Over lubrication

4. Dirty filters

The correct answer is: Over lubrication

Excessively hot bearings on a pump can be attributed to over lubrication, which occurs when too much lubricant is applied to the bearings. While proper lubrication is essential for reducing friction and wear, an excess amount can create a buildup that generates excessive heat. This can lead to increased pressure in the bearing housings and restrict the flow of lubricant, ultimately causing the lubricant to deteriorate and the bearings to fail. Conversely, under lubrication would initially lead to inadequate protection from wear but may not necessarily cause overheating immediately. Aging components can lead to increased friction and could contribute to heat generation over time, but do not directly relate to lubrication issues. Dirty filters may impede fluid flow and affect pump performance, but they are not a direct cause of hot bearings unless they affect lubrication in a more complex way. Thus, the primary cause of hot bearings in this context is over lubrication.