I have had two HB Sonar transducers that were mounted on the Trolling motor .. with the motor stowed the Transducer is on the side ... There is a Black Tar like substance that slowly creeps out over time and drips on the Base mounting.. this substance is something else --- it locked the release lock so I could not get the Motor up to put the Boat on the Trailer -- I had to take the motor off and lay it in the Boat.. The stickey Goo had to be scraped off with a knife... Paint thinner has no effect on this stuff. You can not clean this stuff off to seal where the wire enters with Silicone ---- this is the third transducer that have all leaked the third transducer was on the Back of the Boat