In hull transducer mounting

[Bold Rascal]

Anyone in this forum have any experience trying this?
I have a new Garmin GPS chart plotter still in the box since last Christmas. I want to mount the "transom style" transducer inside the hull and "shoot thru" the fiberglass hull. I DON"T want to pull the boat and put yet another hole in it.

I've read in other forums that this has been done succesfully by several means including:

A 3" or 4" PVC pipe well filled with mineral oil
Siliconing the transducer face directly to the interior of the hull
Toilet bowl wax? Less permanant, quick and cheap
Epoxying the transducer instead of silicone, permanant

I guess the trick is to have it as level as possible and no air bubbles between the transducer face and the hull.

Anyone?

[rpowers]

Can be done

Hi Mike,

I have a Garmin transducer installed in my Catalina 27.

The location is below the holding tank (other side of the head partition).

Just use silicone caulk and it works fine.

I had a lot of anxiety about it, but it turned out to be really easy, and I get a good, accurate, stable signal.

-Rick

[gary gerber]

I have two depth finders installed on my 1970 Morgan 33, one a sweep dial British unit ( reads like a radar screen ) that has been in for thirty five years. The transducer is bonded in the hull and has always worked but the unit lacks the precision of current digital readout units. The second unit and much newer is a Standard Horizon with the transducer mounted in pvc pipe bonded in the hull, mineral oil filled - it has never read properly. Truthfully, I gave up on it.

[Administrator]

No bubbles!

Bill

[zellerj]

I used silicone

You should do this while the boat is in the water to test out your mounting spot.

Put a glob of silicone on the hull, place your transducer in the silicone and make sure there are no bubbles, and look at the unit to see if it displays the right depth. It it does, weight the transducer down a little bit and let the silicone set up.

If it does not display the correct depth, there are probably air pockets in the fiberglass. Find another spot before the silicone sets up.

The key is that there can be no air pockets in the hull, and the only way to be sure of this is to test out your mounting spot by checking to see if the display is accurate.

I did mine this way 10 years ago and all is well today.

Best,
Jim
1982 Catalina 30
Kelleys Island, Ohio

[jhwelch]

Mine is mounted up near the bow where the hull has a small area that collects a bit of water just in front of the mast step.

You might try placing yours using a baggie full of water. Once you find a good spot use one of the methods you have read about to fix it in place.

[TomG]

I used the wax ring method on my previous boat, and it worked perfectly. If you use the wax ring, remember to just break off a hunk of the wax and do NOT knead it. The trick is not allow any air bubbles to be trapped in the wax.

[arthur]

depth finder

when i bought my boat last year it was a one owner from 76 he installed a 3 in. piece of pvc inside the hull amid-ship i was told to fill it with water a drop the transducer in it, i did an it seems to work just fine.i dont think its completely level and not attached-to the hull but works art

[Bold Rascal]

This is great!

I very much appreciatte the feedback on this matter. You don't know how many different mounting scenarios I mulled over in my head before I happened across the concept of just bonding it to the inside of the hull. Duh....

I'm leaning towards the wax method for the time being but will definately use the baggie with water to find the best location.

The silicone is tempting but I wonder if there might be any chemical reaction to be concerned about?

I also like the well idea but the transducer is a large wide beam unit, I would need a 4" pipe and cap. My preferred bildge mounting location forward of the keel is fairly shallow with limited vertical height beneath the floor. Still a good idea though

Thanks everyone for the feedback, Anyone who's sailed the Chesapeake knows how critical a good depth reading is.

[sastanley]

Thanks everyone for the feedback, Anyone who's sailed the Chesapeake knows how critical a good depth reading is.

Especially where you are (Lower Eastern Shore, MD)...I haven't even tried to go anywhere between the Li'l Choptank & Tangier...there just isn't much there except for Crisfield.

I am guessing you must be out of Crisfield?

[Administrator]

Don't forget to recalibrate when done. The mounting method might change things a bit, and sometimes on the Chesapeake, "a bit" is "a lot." Been there, done that, right Shawn?

Bill

[sastanley]

- yup..once or twice, maybe even three times!

[pallen58]

mounting clarification

I just want to make sure that I understand the concept here. On my boats I have had Uniden depth finders. The first worked really well. The current one isn't working since the thru hull was leaking and I solved that by taking it out and glassed over the hole. On the fist boat I bought a puck designed to shoot through the hull. I tested using the baggie full of water technique and that worked great. I epoxied the puck in. I took great care to remove all bubbles. Even using a syringe to pull them out. I have two transducers, transom mount and in hull, and have not taken the time to do anything with them since I don't want it on the transom or putting another hole in the boat.
If I understand this thread I should be able to do what I did before and use either one of those. Right?
But don't forget good chart work, local knowledge and GPS back up.

[Administrator]

Shawn:

Aboard our boat, we call that "cleaning the keel."

Bill

[Bold Rascal]

Oh the wonders of the lower eastern shore

Ahhh come on Shawn, were's your sense of adventure? As far as places to go, well,,,,,, Yeah, there's Crisfield and then there's, Crisfield and oh yeah, Crsifield...LOLOL

That's why I like coming over to Solomons, but then you have to navigate the dreaded "Hooper Straight's" adjacent to kindler gentler "Shark Fin" shoal. Niether of which is really not that bad long as it's not blowing over 20 and the tide isnt roaring, not to mention the occasional "swirls" LOL. Oooh what fun...

I'm out of Mount Vernon off the Wicimimoco...