If bearings on a pump are excessively hot, what could be a likely cause?

Excessive heat in pump bearings can often be attributed to over lubrication. When a pump's bearings are overfilled with grease or oil, it creates additional friction due to the increased viscosity of the lubricant. This often results in a lack of proper lubrication flow, causing heat to build up within the bearings. Proper lubrication is essential for reducing friction and wear, but too much can have the opposite effect.

While high ambient temperatures, a blown oil seal, or a low discharge rate could potentially cause heating issues in a pump system, they are not as directly related to bearing heat as over lubrication is. High ambient temperatures may affect overall conditions but typically would not be the immediate cause of overheating sealed bearings. A blown oil seal might lead to oil loss rather than excess, potentially contributing to heat, but it would usually reduce lubrication instead. Similarly, a low discharge rate could alter pump performance, yet it does not specifically lead to bearing overheating like excess lubrication does.