[R-390] R390/URR PTO Bearings

[Drew P.]

Kevin wrote:

"The bearings in my Collins built PTO have a pronounced rumble to them, dried out grease is my bet.
Does the group have any words of wisdom or warning to flushing them out and re-greasing or is replacement the only option?"

These bearings are relatively lightly loaded and should last a very long time, and so pitting due to wear is not so likely. The other cause for pitting would be corrosion. There have been on this forum reports of the PTO's internal dessicant packs breaking open and making a corroded mess of the PTO's insides - such could include the bearings. If your PTO's internals are clean and uncorroded, chances are that the bearings are not pitted.

With a good cleaning and relubrication, I fixed a similar problem, hard-to-turn tuning knob, cause of the infamous R-390A Wrist Syndrome, in a Cosmos PTO (R-390A). I soaked the lead screw, lead screw nut, and lead screw bearing for several days in lacquer thinner. The lubricant of choice would be a light synthetic grease. Synthetic is preferred as it does not gum up or solidify as readily as does conventional grease.

Drew