I have an E27, so I guess you are talking about the bildge?...If so, I dont think there would be any serious reason not to, but I think there are better places, for instance, mine is installed in the starboard seat aproximately amidships, and shoots through the hull, thus eliminating any new holes in the hull, and it is accessable. I guess the things I would be concerned with installing the transducer in the bildge are: interferance with the bilge pump; slimy deposits on the transducer over time; volume of sump slightly dimminished; Plus, I dont know what the advantage would be. Have you given thought to how you would install it? The sump does get pretty narrow at the bottom (I've had to retrieve my favorite pliers from the depths of it)