Better singing than screaming all the time for no reason, I suppose.
I have a propeller question some one might be able to advise me on.* I have a vibration that shows up at 1500 rpm and persists to 1650 rpm.* Since we almost always run at 1250 - 1350, it's not an issue.* There are new cutlass bearings and the shaft has theoretically been properly aligned.* My questions are:
1.**Would an imbalanced prop have any negative effects when run in the sweet, no vibration range?* Say on the cutlass bearings?
2.* If removed and balanced, how likely is it that a vibration shows up at another rpm range?
3.* The prop was tuned by the PO and this range vibration has been there since I bought her in 2003.* How likely is it that the prop wasn't balanced properly, or is this likely to turn out to be a function of factors other than prop balance?
4.* I asked a very experienced CAT mechanic about this, and he said that 3306s all vibrate under load at certain RPM ranges.* He said that they had spent a lot of hours on engines trying to balance them to no avail.* Does this make sense?* Sunchaser, I think you have experience in this area, correct?
I know I can get ideas on these from a prop shop, but any comments on your own experience in this area would be welcomed.