In-hull transducer for the W32's

  • July 07, 2014 10:03 AM
    Message # 3039365
    Deleted user


    Last summer durning a hull modification, I had the thru-hull transducer glassed over to reduce a measure of drag with the idea that I would install a "in-hull" transducer. Would anyone care to share their experience with in-hull transducers? I want to get some ideas before I commit to a certain location for installation and/or model of depth sounder. Naturally, I'm looking for accuracy, reliability, optimum position/location, and methods used for installation.


    Dan - Mithrandir, #310

  • July 07, 2014 11:43 AM
    Reply # 3040010 on 3039365
    Hi Dan,

    We installed an Airmar p79 to go with a ST60+ head unit.  I installed it under the starboard settee just in front of the hanging locker.  It is installed about 3 inches up from the "bottom" of the settee.  The p79 transducer is adjustable to meet the dead rise of the hull. I found the very last notch worked perfect on our boat (22 degrees). 

    To install it I sanded the hull at the spot and used caulk to glue the ring down. So far it has been working great. 

  • July 07, 2014 12:29 PM
    Reply # 3040036 on 3039365
    Deleted user

    Thanks Tate!

    I had a P79 on order, but changed my mind because I was getting conflicting information between Simrad and Airmar. I think Airmar was correct, however Simrad didn't seem too keen on working with "old" stuff (my original depth sounder is a Simrad IS12), they would have preferred me to upgrade to a IS20 with thru-hull transducer combined with water temperature and knot meter. I'm trying to keep from cutting another hole. Well, I'll rethink the P79...again. :)

    I don't need fish finder technology, I just want something that measures accurate depth.

    Best to you,


  • October 17, 2014 6:41 PM
    Reply # 3126539 on 3039365
    Deleted user

    Hey Catherine,

    A bit late. We have a Lowrance Chart plotter (HDS7, 2nd gen) and depth sounder mounted in the same location as Tate's and have had no problems except for our first try where we had a air pocket which gave us inaccurate reading. We reinstalled again and have excellent results.


  • February 09, 2015 7:01 AM
    Reply # 3221358 on 3039365
    Deleted user

    I have a Garmin 541S and shoot it through the hull with no problems.  I used a spare piece of 4" diameter PVC tubing and cut it to fit snug and vertical, glassed it in and fabricated a disk "donut" to insert about an inch below the top through which I attached the transducer (you'll want a spare nut from Garmin to secure it).  I drilled a few holes in the donut perimeter and poured in some RV antifreeze to submerge the transducer, ran the lead through a PVC cap (don't cement it to the tube), swabbed on some silicone to seal the hole and voila!  Works great.  If you need some sketches to visualize it all just shoot me an email. -Tom