BAM MARINE OF FLORIDA I HAD TO REPLACE MINE AS WELL. IS YOUR WATER TEMP OUT AS WELL. MAY BE SAME TRANSDUCER. HAVE YOU TRIED RE-PINGING THE SETTINGS. ALSO HERE IS THE BEST ADVICE. WHEN CHANGING A THRU-HUU TRANSDUCER, MAKE SURE HTE BOAT IS ON A LIFT OUT OF THE WATER. I PURCHASED MERCURY-MERCRUISER 79-8M0122505 THRU HULL DEPTH/EMP TRANSDUCER 10 FT 20 DEGREE. WEB PRICE $330.26. HOPE THIS HELPS. DREW