Depth gauge transducer

[Mark Williamson]

The depth gauge/transducer in my Kelt 7.60 started acting up last summer and i'm looking to start by replacing the transducer with an in-hull type (possibly an Airmar P79).  The current thru-hull transducer is under the v-berth (the small storage area closest to the table).  Does anyone out there use an in-hull type and if so where is it mounted and what type is it?  Thanks!

[Sidney]

Hi mine is under the chart table in my Kelt 8.50. It is just glued to the hull. I also have a fish finder and the transducer sits on the hull under the aft berth with a good dollop of vaseline between it and the hull.

[JJJ]

Hi Mark,

We replaced ours on our Kelt 7.6 with a Uniden QT206 (see pic) for approx $120 CAD.  It is an in hull type (no drilling required) and can be installed in the same location as your existing one.  It takes a bit of time and some trial and error, but the instructions provided are clear and self explanatory.  The gauge will likely be smaller than your existing one, so the hole in the panel will be too large. We made up a bushing to accommodate the difference.  This system is very accurate and works well.  So far we had no problems with it and are quite happy with it.

JJJ

[Mark Williamson]

Thanks.  I picked up a p79 transducer on eBay.  I'll give that a shot with my existing raymarine guage  then take it from there.  I hadn't seen the uniden.  Looks like an interesting option.  Good to know we can use in-hull transducers in Kelts.

[Mark Williamson]

The P79 in-hull transducer didn't work with the old raymarine gauge (even when it was in the water).  So the old gauge was bad.  Bought a new raymarine i40 which didn't work with the old transducer but worked with the P79 in the water.  So the old transducer and gauge were apparently both bad.  The P79 initially wouldn't work when tested at the bow location.  After playing around with it got it to work.  Installed the transducer (it sits in a cup of anti-freeze which is siliconed to the hull.  It worked for several days sitting in the slip then stopped working.  Couldn't figure out why.  So pulled it out and tested in the starboard sail locker.  Worked.  I think the fiberglass is thinner there.  So siliconed the cup today.  I assume it will work from here on out.  Quite the exercise...

[Mark Williamson]

Ok...  I think the issue was that the P79 transducer sits in a cup of liquid and there is too much loss going through the liquid and the hull.  I ended up sticking the transducer direct to the hull with silicon caulk and seems to work fine now.