I have an OS 46LA installed in a WOT4 that has never worked particularly well. The engine tunes beautifully whilst attached to terra firma, but once in flight for approx. 5 minutes it's revs change from low to high and a short while later the engine cuts out. I have heard (through my local club) that there has been trouble with some LA series units experiencing an expansion of the liner as the engine heats up. Could this be related to my problem? If so how do I go about getting it fixed?

Chocky.