Just bought a Garmin 540S plotter with sounder< I would rather mount the sounder in the boat rather than on the outside, Does formula have a good spot in the hull to mount this inside? 2002 Formula 312, fastech

get you some Plumbers Putty from Home Depot and stick the transducer down with the putty to test it in different areas of the Hull ... It has to be a solid spot ...the transducer wont shoot thru if there is an air gap ...

I have a '98 312 and a Gamin also, I tried the hull in the engine compartment and could not get it to work. I also tried the area under the step in cabin area by the sliding door, it also would not work. I was told you would have cut a hole in the white fiberglass grid system that is bonded to the hull to get the transducer to actually touch the hull surface.

Another method of testing is to fill a zip-lock bag with water and put it against the hull surface.

Does anyone know where the factory installed transducer is located on a 312?

If you find a location that works please reply.