flyrotary@lancaironline.net Mailing List Archive

Not good indeed.

Two or possibly three causes for this. but before detailing these, take note of the "larger sized rollers" in the pix. Those look like the input shaft has sheared off the drive pin. Probably caused when a roller got in the gears and locked up momentarily. I'm kind of surprised no one noticed any of this mayhem going on during testing. The dripping oil at the input shaft was no doubt due to the seal being distroyed by heat. The race melted for the same reason.

1. No oil to the thrust bearing. It is not enough that there was oil inside the housing. Take special note of the small oiling passage in the input shaft that leads from the pressurized oil cavity where the pilot bearing is. It then goes directly to the inside of the thrust bearing where it flows through the bearing and carries away heat (important on roller bearings at high speed). Drip or splash lubrication is NOT adequate. Check that the thrust bearing oil passage is not obstructed. Oil for the drive must come from the oil system after the filter.

2. This same type failure happened on another drive when a late model input shaft was used with an early adapter plate that did not have the deep bevel for clearance of the shaft radius. Check adapter plate for signs of interfearance.

3. Not likely, but check to be sure the snubber(s) is in place to insure proper end play of input shaft. if it is excessive, rear race of thrust bearing can drop down and cause all manner of problems. B drives may have 1 to 3 molly impregnated nylon snubber washers. All that were shipped with drive should be installed.

I assume the drive is on it's way back so I'll let you know what I find.

Tracy

On Mon, Apr 14, 2008 at 11:24 PM, Christopher Barber <CBarber@texasattorney.net> wrote:

Correct me if I am wrong, but the stuff inside my RD-1B shown in the attached pictures, I am guessin' is not good. For as much as I know about PSRU engineering, maybe the loose pellets are an "added feature."

While I was remounting my newly built 13b back on to the rear of the Velocity I decided to try to hunt down a pesky PSRU oil leak that had been problematic before the engine tear down/build of the last few weeks. I could not see anything obvious, so feeling emboldened after building my second gen 13b with all new housings last week, before I mounted the re-drive onto the newly installed engine, I removed the through bolts holding the PSRU together

DOH! What the hell are all those little pellets and fragments of black plastic??????

What gives? This unit was on the engine for about 6 of the 8 hours on the old engine (those first two unloaded hours may be part of the reason for my need for a new engine<??> What went wrong? What is the cure?

I am thinking I need to crate this up and ship it off to RWS for review and repair. Maybe it will get there about the same time as folks return from Sun & Fun.

I was so happy putting everything back together following the engine build. I thought I would be ready for first start tomorrow. Well, since I am well acquainted with Murphy and knowing full well that Murphy and his little law is quite optimistic, I am on semi-hold.

Thanks for any insight.

All the best,

Chris

Houston

--
Homepage: http://www.flyrotary.com/
Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List.html