I have a Pettyr nasty vibration that has me nuts trying to isolate it. it is mostly noticible at the tail boom & vertical fin but the whole machine shakes. The tail boom is actually vibrating up & down but when your looking at the vertical fin it has a noticeable side to side vibration.

This is what I have already tried Checked the tail rotor shaft for end play. Found none. Checked balance of blades. good, changed main shaft and hub,swapped out the belt, tighten every nut & bolt on the head & finally checked the phasing.

does anyone have any suggestions!!!

thanks in advance
Santonomos

I had the same thing on my maiden flight and the first advice I was given was to pull those dampers out and oil them! The manual does hint at this but let me tell you, soak those buggers in car engine oil and stick em in while still dripping with oil. It is suggested that you do this once every two weeks or so because they dry out with use. It fixed my ship right up, and I was relieved cause the only other thing is a misaligned flywheel/clutch/shaft assembly which is real critical. Mine was well within the given tolerance but the thing shook like crazy. Now that's part of my regular maintenance and after about 25 litres of fuel the shakes still haven't come back...

I had vibration due to bad engine tuning.