I have been given this plane which is already built with all the accessories. It came from a friend who didn't have any success with it. So, he asked me to put it back together and see if I can fly it. I do have expericence flying, so I don't think this is a challenge to fly. However, the O.S. Max engine seems to have been lying up too long, now it won't turn. Can anyone tell me the best method to free the crank. Any help would be appreciated.