Thank you all for the good advices.

Ron. This afternoon I went to the field and did exactly what you suggested, I did it with the engine running for every single test at the end of all the testing I found out that the leakage was coming from the nose retract only when the engine was running, I also notice that the retract body was not seating flat but with a twist, this twist was pushing the retract shaft down making the air to leak.
G4guy you also gave me a good idea to solve this problem.
But I like to thank the members that responded promptly.
Thank you all.

Carlos