Tony, You are right you should never man-handle a servo by manipulating the surface. I gently move the surface to look for gear problems. If you apply a quick rotation or quickly change direction you may damage the nylon gear used as a fuse in a metal gear servo. Never push a Flap to full deflection=over center, and then manually try to return the flap.What I do is feel the sevos mesh looking for smooth operation. If you suspect a damaged gear move the surface away from center and turn your radio on. Move the surface you suspect by radio command. A damged servo will usally grind and or respond with a jerky motion and gradually lose its ability to hold center. Best wishes Larry RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
