Put the boat on the trailer and when trimming up motor (off of course) to put on the transom support heard a 'thud' from mid section, trimmed it down and heard the thud again. Trim all the way up same thing and then back down. Boat performed fine when in the water. Any suggestions? Only heard it when boat was on trailer and the motor was being trimmed up or down, like something was flopping around inside of it.
