🔍 Key Concepts

• lubrication of rolling-element (ball) bearings in pump motors • effect of too much grease vs. too little grease on bearing temperature and life • how grease actually circulates and moves inside a bearing during operation

💭 Think About

• What happens to the balls in a bearing if there is so much grease that they cannot freely roll and push grease out of the way? • Does an over-packed bearing usually run cooler or hotter, and why would that be? • Which choices describe a normal, healthy flow of grease, and which describe a restricted or abnormal condition?

✅ Before You Answer

• Identify which options describe a negative consequence that commonly occurs when a bearing cavity is overfilled with grease. • Eliminate any option that sounds like a description of ideal lubrication and cooling. • Think about whether over-packing would make it easier or harder for grease to circulate and carry away heat from the bearing.