A friend gave me a 4-5 year old Avistar with an OS LA 40 engine that has 6-8 tanks of fuel through it and runs very well, the first problem I have is at idle and through most of the mid range the fuselage seems extremely noisy. It's hard to describe but it sounds like there are loose metal pieces laying in the bottom and they are bouncing off one and another. I've went over the engine and mounting several times and everything is tight. I wonder if this plain bushing motor is just noisy by nature?
The second thing I question is during flight if I roll the plane right to inverted the engine will stumble as it goes inverted( Makes things very exciting) but then it seems to be fine it doesn't seem to do it if I roll left to inverted. It will fly around all day inverted and not miss a lick, and doesn't miss when I roll back upright.
I have an older Magnum 40 Pro I'm considering trying.
Any advise/ comments would be appreciated.
Puzzled
Thanks Kev