Thanks for the help guys. Bill I did see Norm's installation and he's given me advice via offlist email. Between a recent conversation with a Garmin tech and Norm, I'm thinking that maybe the paint on the inside of the hull is inhibiting the transducer. I have sanded the paint off and will try the silicone method there. Also, Bill, Garmin doesn't make a round transducer for my unit. The technician said that the round pucks they make for other units would not be more effective than the transducer I have. He said it should work on a solid hull up to 5/8" thick. Edward, I did try the method that you mentioned, but again it was with the painted hull. I think next I try silicone like I mentioned above. I hope it works, but it's good to know that you have found an external mount the works. Thanks William. I keep you all posted on my progress. Yours for a fair tide, Rick