Transducers for Depth Sounders
The hull is solid fiberglass. But your problems could be one of these: 1. If the laminate is poor with air bubbles where you placed the transducer, it could give you problems (not likely) 2. Whatever adhesive you used to stick the transducer to the hull might have air pockets in it suggesting problems (likely) 3. The transucer is not strong enough to shoot through the hull (most good brands are capable of shooting through an inch or inch and a half of sold hull) 4. Something is wrong with the unit itself (likely). Personally I like to drill the hole through the hull and caulk it with a polysulfide (Life Calk)- never silicone below the waterline or an adhesive sealant like 3M 5200 (you'll never get the thru-hull out if needed). The mushroom transducers used in most sailboat instruments are easy to install with a hole saw the correct size to fit. Older styles with recessed heads required special tools. They aren't used much anymore.
