Real World Solutions, Inc

Home of RA Classic Apex Seals and RA Super Seals

[ Home ] [ Search ] [ Recent Updates ] [ Contact Us ] [ Directions ] [ Site Map ] [ How to Order ] [ Guestbook ]

All RWS Gear Drives

Mandatory Inspection

September 1, 2003: During a routine inspection of the RD-1B gear drive on the RVotter, Tracy noticed some unexpected end play in the propeller shaft. The source of the end play was eventually traced to a shallow groove warn in the front bearing retainer. This was caused by insufficient clamping force on the front bearing outer race. When the grease in the sealed bearing was cold, and the engine was started, the outer race would spin in the gear housing.

This condition is NOT likely to cause an in flight failure, but could eventually lead to deterioration of the bearing grease seal and gradual loss of lubricant. Inspection of the back side of the prop hub will reveal grease coming from the front bearing if this were to happen.

The clamping force, which is controlled by the clearance between the bearing and the front bearing retainer, was increased shortly after the early RD-1B on Tracy's aircraft was built. However, we still recommend that ALL RWS gear drive owners, check for this increased end play as part of your pre-flight routine.

To do this, simply grasp the prop and PULL towards you, than PUSH back smartly. If you notice any end when performing this test, you'll usually hear a mild "thump". Prior to your next flight, remove the front bearing retainer and move it forward on the prop shaft as far as possible. You can than visually inspect the back side of the retainer for a groove where the outside race of the front bearing contacts the retainer. If you have any doubt about the condition, use a small took to feel for a groove in this area.

If the bearing retainer is severely grooved, the bearing and retainer will need to be replaced by sending the prop shaft to Real World Solutions. We will provide the replacement parts at no charge.

If the groove is minor i.e. no more than .005 deep, the drive can be repaired by removing the prop shaft and bearing from the drive, and installing a .006 inch shim behind the front bearing, then reinstalling the prop shaft and front bearing retainer. Contact RWS for this shim if you can't fabricate it yourself.