Well I've had a few flights on my new Alpha 60. Flights were fine, except we are having some engine trouble...basically the high end needle valve is not "responding in a predictable manner", as my instructor put it. At first he thought that something was blocking the line, so we flushed them, and additionally replaced the glow plug. Helped for a min, then back to the problems. After a while he noticed repeated issues with bubbles in the fuel lines. His theory is that the fuel is foaming due to vibration and the bubbles are being sucked into the lines. Upon inspection of the tank, it is solidly secured with balsa, and the vibrations of the frame appear to be causing the problem. He states he thinks it is a design flaw with the Alpha 60, and feels that I should remove the balsa surrounding the tank and pad it with foam instead.

Now, I'm a beginner, and I don't particularly want to go attempting to cut up my new airplane to satisfy a theory. So here I am, asking you guys.

Has anyone else heard of this problem?