Instead of replenishing bearing grease... pump oil into it: Fact or fiction?

We all want to save time and money when it comes to replenishing bearing grease: Have you ever tried, instead of replenishing bearing grease, to pump oil into the bearing, with the hope of “rejuvenating” the grease? This is a rather uncommon practice, but it does happen.

The short answer is that pumping oil into the bearing is in no way a substitute for replenishing bearing grease. As you probably know, grease is a product of dispersion of a thickening agent in a liquid lubricant. Over time while in service,