Hi, try to get in some silicone spray int the system it will take care of a minor leake. When I have leakage in the gear system I also try to put some low viscousity silicon oil into the tubing and after doing that it is usually leakage free.

When I was building my Rafal I had to take a part 2 out of 3 cylinders and lubricant all the O-rings inside, then it was airthight, a note though it was not the standard mecanisms including in the kit.

Please send us some picturers of your rafal, engine instalation and so on, it always good to compare instalations.

Best regards, Kjell-Åke