When lubricating a pillow block bearing, what should be done before pumping grease?

Pumping grease through the grease fitting of a pillow block bearing should be preceded by attaching the coupling to ensure that the grease can effectively reach the bearing. This method allows for a more controlled and efficient application of grease. As old grease is expelled from the bearing, it indicates that fresh grease is reaching the internal components, which helps in maintaining optimal lubrication and reducing wear.

When new grease enters the bearing, it typically pushes out the old, contaminated grease, which is essential for the bearing's continued performance. This practice not only ensures that the bearing is receiving proper lubrication but also helps to prevent any potential damage that can occur if old, degraded grease remains in the system.

In contrast, checking the bearing temperature, removing the bearing, or inspecting the grease quality, while important maintenance practices, are not prerequisites for the grease pumping process itself and do not specifically address the proper procedure for lubricating the bearing as directly as coupling the grease gun to the fitting.