through the hull transducer..how do I install one???

[SparkieBoat]

I have a 1979 17.5 McKee craft..it had a 6" round pipe in the bottom that had the old transducer in it, it was attactched to the bottom with some kind of white silicone adhesive looking stuff..My question is will plain ole silicone adhesive work or is it some kind of special stuff??? I am installing a Eagle Cuda 300..also will it work with this depth finder???

 

[xxxflhrci]

Re: through the hull transducer..how do I install one???

My understanding is that silicone won't work because it will dry with bubbles in it. You need a slow curing two part epoxy from what I have read....Mine came with the epoxy. I took the boat out on the lake with water in the bilge and put the transducer in several spots trying to find the best location. I used a sandbag to hold it down while the boat was underway. I took note of the spot, took the boat home, drained and dried the bilge, and glued the transducer down.

 

[smokeonthewater]

Re: through the hull transducer..how do I install one???

through hull or shoot through hull???/ do you have a 6" diameter hole in the bottom of your boat? if you are gluing to the bottom then use epoxy.... you want something hard... silicone will not transmit sonar well so will weaken your signal

 

[SparkieBoat]

Re: through the hull transducer..how do I install one???

the 6" pipe goes thru the floor and stops at the hull..and you can fill it with water..I believe the transducer has to be in water is why they did it like that. So anyone know what kind of epoxy??? I guessed it was like this from the factory..maybe not. I will post a pic tomorrow

 

["G"]

Re: through the hull transducer..how do I install one???

For years we installed transducers in silicone with good result. The trick was a good solid bead of silicone with no air in the "bed".

Through hull applications required a "block" machined into a teardrop shape (inside and outside the hull) so the transducer sat vertically. Not a good option for trailered boats.

As for the 6" pipe in the boat... that's the best of all options when done correctly... fill the sealed pipe with antifreeze and cap it off with your transducer installed in the cap vertically. Again... be sure there's no air inside the pipe or you'll have issues.

 

[smokeonthewater]

Re: through the hull transducer..how do I install one???

i used "5 minute epoxy" from walmart, hdwr store etc

 

[SparkieBoat]

Re: through the hull transducer..how do I install one???

thanks guys, yes the pipe is sealed, but does not have a cap, it sits under my false floor which runs up the middle of the boat. I could probably find some kind of pvc threaded fitting that comes with a cap, to attach to the pipe to seal it off and keep the anti freeze from spilling out. it looks like they used silicone on the original install, it is soft and pliable even after 30 years, though it has been submerged..I will try the epoxy, but I do want something that can be removed without too much trouble. Thanks again for the help and input.

 

[Mark_VTfisherman]

Re: through the hull transducer..how do I install one???

I never had much luck with silicone under water. I would think that 5200 would be a better, longer lasting option.

 

[grego]

Re: through the hull transducer..how do I install one???

Through the hull? use "rtv." works well, have used mine for 10 years with NO! problems

 

[Mark_VTfisherman]

Re: through the hull transducer..how do I install one???

Through the hull? use "rtv." works well, have used mine for 10 years with NO! problems

Probably someone has used Jiff Peanut Butter and Shoe Goop, too, but that don't make it a good idea. Glad you have had good luck with it, though.

RTV has it's place, and it works well in a lot of applications it is intended for, but not in a boat or below the waterline as far as I am concerned.

Some Lowrance manuals specifically say not to use rtv.

</edits>

 

[SparkieBoat]

Re: through the hull transducer..how do I install one???

i do not need to seal the hull...only attach the transducer to the hull...the pipe only goes to the hull, the old transducer appears to have been attached with white silicone caulk. There is no hole in the hull

 

[Mark_VTfisherman]

Re: through the hull transducer..how do I install one???

i do not need to seal the hull...only attach the transducer to the hull...the pipe only goes to the hull, the old transducer appears to have been attached with white silicone caulk. There is no hole in the hull

Yup, I got offtrack:redface::redface: Sorry.

Silicone absorbs sound... opposite of what you want.

If you go to Eagle's website you can download a manual and get what Eagle says.

I don't know about silicone, as I have always been told that silicone is bad, but Lowrance has a "special" epoxy product to bed it in. Also, silicone has not given me the same performance as the urethane products I have used in building construction.

I have not done a shoot-through installation myself but I like the idea A LOT.

 

[SparkieBoat]

Re: through the hull transducer..how do I install one???

I was going to post a pick, but never did. I sometimes lack the vocabulary to accurately say what I am trying to. I read the installation manual that came with the depth finder, it did not address the issue at all. I assume that a shoot through the hull would work better, if you have trouble getting readings at high speeds. thanks for all of the input, I really do appreciate it.

 

[grego]

Re: through the hull transducer..how do I install one???

Fricken Duh! Rtv!!!!!!!

 

[Mark_VTfisherman]

Re: through the hull transducer..how do I install one???

From a Lowrance user's manual: "Make certain the area is clean, dry, and free of oil or grease. Build a small dam out of caulking compound or RTV around the mounting area. It should be at least 1/2" greater in diameter than the transducer. Use a good two-part epoxy that sets up rock hard. Do not use 5 minute or ?fast setting? epoxy. Do not use RTV silicone rubber adhesive or any other glue."

The idea is to transmit transducer pings and allow the transducer to "hear" the return, not to dampen the pings. Of course it DOES say you can build your bedding dam out of RTV or other caulking...

 

[grego]

Re: through the hull transducer..how do I install one???

I have fishfinders forward and aft, sitting in puddles of rtv and one at helm that is factory. they have been reading close to each other for a long time. I think I will stay with what works!

 

[Texasmark]

Re: through the hull transducer..how do I install one???

You have a lot of good info on here. You are dealing with sound and sound travels through solid objects better than soft objects and certainly better than in air. I always used epoxy and made sure that the unit was firmly against the hull.

Before you go drilling a hole in your boat, you might run a test. Get a zip lock freezer bag and go out to the kind of water you will be running in. Lower the unit over the side and take note of something in the structure that you can remember.

Put some water in the bag with the transducer and set it inside your boat in a convenient spot, like a foot forward of the transom and a foot off centerline if the hull is flat there so that there won't be a lot of turbulence. If the difference between the two readings is minimum and to your liking, epoxy the sucker inside the boat where you had the bag. I'd certainly do that before I cut a hole in the hull I might not need.

Mark

 

[grego]

Re: through the hull transducer..how do I install one???

sparki. sometimes the old is better than new. If you want "depth at speed" the older flasher unit is better!! and cheap. It does two things "it sends a signal and recieves a signal". The new fishfinders have to colate a lot of info "before" you read it on screen. For real time readings, get a flasher unit!

 

[SparkieBoat]

Re: through the hull transducer..how do I install one???

Thanks to everyone..I really appreciate all of the very good advice. God Bless

 

[Texasmark]

Re: through the hull transducer..how do I install one???

sparki. sometimes the old is better than new. If you want "depth at speed" the older flasher unit is better!! and cheap. It does two things "it sends a signal and recieves a signal". The new fishfinders have to colate a lot of info "before" you read it on screen. For real time readings, get a flasher unit!

Yes and no. They still show the bottom, regardless of all the "stuff" inbetween.

Mark