Upper Sheave Bearing
We have a problem with the upper sheave bearing on our R44. It's a new (106hr) Raven II, which had the bearing changed at the 100 hr service because of grease throw. On collecting the aircraft, there was a very high frequency vibration which wasn't present before the service. We were assured that all was well - TR shaft runout check, 30 min test flight, MR track etc completed OK.
An engineering inspection was carried out 2 days ago, due to telatemps turning a light greyish colour; 2 new telatemp strips were applied, and a 30 min air test (with engineer) completed satis. One of the new strips is a lower temperature strip. The vhf vibration doesn't manifest itself any more (or else I've just got used to it).
Now we've got 2 black marks at 82 degrees (one on each strip) after yesterday's 30 min flight - clearly there's a problem.
Anyone care to comment? The machine is of course grounded...
Cheers, WW