I put my 19 foot Sting Ray into the slip yesterday. The boat has a Merc. Cruiser 140 and I noticed air bubbles escaping from the bolt on flange gasket off the upper unit where it connects to the back of the engine. Should I be concerned, it was a very small leak I believe, but not sure if this will cause me problems. The boat is now in the slip, and the flange is of course above the water line.