I was following an earlier post by Dave Congdon and still having no luck getting a reading. I chose a spot under the starboard rear berth bilge access sanded it to bare fiberglass about the size of half dollar. Did the water bag test and tried Vaseline on the transducer and nothing. I tested it by dropping it in the water and it's working fine. I had the bottom painted professionally over the winter, could that be the problem?
H23.5 transducer placement and install
- Thread starter Chris Flanagan
- Start date
Make sure you are against the hull, there should be a noticeable curve to the surface. I think the ballast tank extends behind the centerboard trunk by a few inches at least. Here's a link to some of the hull drawings from the manual, you should be able to get at least a rough feeling of the construction from them. I seem to remember needing to go quite a bit off-center on my H-19 which had similar layouts.
http://www.ayesail.net/sailing/Hunter/Hunter19_23_26/target72.html
http://www.ayesail.net/sailing/Hunter/Hunter19_23_26/target72.html
I chose a spot fairly off center, a few inches from the ballast tank. I will review the drawings you sent and consider a new area. Thank you!
There can be no air voids in any of the material the transducer sit in an you have to build up the sides till the bottom of the transducer is not exposed
Er, this might be a touchy subject, but a balsa or foam core hull might well absorb this energy. I know Sir Dave will attest he has never witnessed a layup of balsa. I'm just not certain if this was for all model years. What year is your ship?
Hi Chris, to the best of my knowledge Hunter built there boat hulls with solid FRP below the waterline and balsa core above. I located our depth transducer right next to the shaft strut on our 1991 boat and it worked just fine during the water bag test and later the final installation. That was in 2005 and no problems since. Try a different location, perhaps forward of the keel. Please let us know the outcome.
Santa brought me a little Humminbird HDR 650 and I've resigned myself to a transom mount. Actually, I'm heading towards a pole mount. Yup, I want to suspend it from a pole where the mast crutch normally sits and get it deep in the water on a non-ferrous blade of some sort. Then just shove the meter into the top of the pole and run some power to it (maybe a small solar panel+NiMH cells). It would be very visible at the back of the cockpit, where I normally sit tending the engine - ha!
On my 23.5 I put the transducer in the center access area under the aft berth, so a bit farther from the ballast tank than where you described. Toilet wax works great.
So what meter/display do you use, and where is it mounted? [Edit] Oh, and how does it work when heeled over a bit? Or does one really care to watch depth at that point?
It was a raymarine st40 w/transducer... I also had an old humminbird in the same spot and they both worked well. I never happened to look at the display to determine if it wasn't reading due to an extreme heel angle... Just holding on with a big grin at that point I guess...
When Dave installed mine he tried finding a spot using the transducer in a baggie of water technique. I never saw a reading on the display. When he put plumbers putty down and smushed the transducer down in it bingo. Great reading. It's been working great for 3 years now.
I mounted the Hawkeye display under the compass just to the right of the companionway in the cockpit. As far as reading it when heeling time will tell, and your right I probably won't care at that point! Thanks for all the help!
Sorry for this unfinished business. I did get the depth finder to work by placing it in the center opening under the rear berths. I still have issues with intermittent readings I believe I can resolve this by sanding some more and remounting it in more plumber's putty. Thanks for all your help!
the key when installing without a thru hull is to sand the gel coat off getting a smooth surface and then emersing the transducer into what you are attaching with like the plummers putty with Kermit boat, H 260. There was never balso core in the 23.5 and please do not reference that junk again on the 23.5
When I mounted my transducer to the inside of the hull I used the center aft bilge access, like others have mentioned. Ive had great performance in that location. I didnt do any sanding of the gel coat. I just used epoxy and let the epoxy set with a weight on the transducer so it made solid contact with the hull material. Im not sure why so many want to use a putty to attach these things. Its clearly inferior to epoxy. Its not like epoxy is some expensive and hard to use product. I highly recommend trying epoxy.
Side note: When I was testing locations the water bag test did not work here. But using petroleum jelly it did work.
Side note: When I was testing locations the water bag test did not work here. But using petroleum jelly it did work.
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The manufacturers instructions recommend the epoxy, I was nervous about the permanence, I will give it a try, Thanks for the advice,
Regarding wax/putty vs epoxy.... I have used all 3. They all worked they same, and the only one I regretted using was the epoxy when I decided to switch depth displays.
Experience is the best and one thing by sanding the hull first off helps to give you more of a flat surface. As for the gel coat it too had air bubbles probably from the application of it in it. That was another reason. As for the location of the depth finder, well there is only one place in the water ballast boats and that generally is under the rear berth adjacent the bilge pump. Do not even think of drilling thru the ballast tank as that is the dumbest idea of all. As for attachment I have tried all and of course the best is thru hull but there are ways to get around it. As for application of attachment using epoxy, plumbers putty, 5200/4200, emmersion methods inside the hull and so on, I like the plumbers putty and it works. With anything though you have to make sure there are no air bubbles when attaching inside in the epoxy, plummbers putty and so forth. The use of epoxy I never even suggested. It is heck to get off first and what if you make a mistake and there are air bubbles between the transducer and hull? Not so good and cursing. That is why.
As for the water bag trick and you do get a reading, suggest placement there. I note petroleum jelly was used but when cleaning that up, you have to make sure all of that is cleaned up or adhesion will not take place. PS Plumbers putty was suggest by a member on the production line as to attachment many years ago but did not think that was viable. I was proven wrong by those who did use it.
As for the water bag trick and you do get a reading, suggest placement there. I note petroleum jelly was used but when cleaning that up, you have to make sure all of that is cleaned up or adhesion will not take place. PS Plumbers putty was suggest by a member on the production line as to attachment many years ago but did not think that was viable. I was proven wrong by those who did use it.