Thru hull transducer mounting

[bigredsnapper]

21 foot fibreglass boat and I need to buy a new transducer. Any advantage to the thru hull? Does it affect performance? I usually fish deep(150-200ft)and prawn from 300-400ft. Thanks in advance for your knowledge. My sounder is Lowrance X-107 dual freq.BRS

 

[Charlie]

Not really - more of preference than anything, on a 21'.

Personally, I prefer thru hulls, but I did install a thru hull on a 12' Zodiac once and it did create a problems with the water flow and had to change it out.

 

[bigredsnapper]

What I mean is you get a special transducer and resin it to the inside of the hull. BRS

 

[scott craven]

You don't need a special transducer, and i would be careful about what you use to secure it as some products will affect the signal.
You can actually just place it in the bilge, as long as there's
a little water it will read through the hull.

 

[Copper Moon]

You can also set the transducer in vaseline. I fish the same areas as you and it worked ok. You would have to watch out for air pockets.
I have also let mine just sit in the bilge in water and it worked well until it was jostled around.

 

[chris73]

I have seen several brands sell extra tranducers for through hull installation. Is this then just a money grab?

 

[salmon9]

My understanding of the value of truhull transducers is they typically perform better when the boat is moving and most truhull ducers are of better quality and power than transom ducers. Air between the transducer and water column will interfere with the signal and result in poor readings. A transom mounted transducer will experience more air as the boat moves forward with speed, while power of the signal and location mounted on the transom may help to maintain bottom, detail will be lost. Buy the best transducer you can, Airmar makes quality truhull transducers.

 

[Charlie]

A tru-hull will perform a little better as they are mounted well forward of your props, so, you won't get as much interference. Which, is why I prefer tru-hull, but it isn't that much better, if you are comparing the same transducers?

The transducers (tru-hull, in-hull, transom) are the same quality provided you are comparing the same transducer, with the same construction, be it plastic, bronze, or stainless.

If you are comparing 1kw and 3kw, there is improved quality as you start getting into your larger transducers. Just get your checkbook out!

I have no personal experience with "In-hull" transducers, but I agree I would be looking at least a 50/200 kHz, 1 kW RMS, High-performance, Urethane... and it would be one of these:
http://airmartechnology.com/airmar2005/ex20/RMProducts/OpenData.asp

 

[TenMile]

I've seen guys take a PVC pipe, cap the bottom and caulk the transducer inside it. The caulk the pipe inside the bilge using 5200 ensuring no air gaps. Once everything tests ok, they fill the pipe with antifreeze and place a cap on top. That way, the transducer will not freeze and crack.

TenMile
<'((((><

 

[Copper Moon]

quote:Originally posted by TenMile

I've seen guys take a PVC pipe, cap the bottom and caulk the transducer inside it. The caulk the pipe inside the bilge using 5200 ensuring no air gaps. Once everything tests ok, they fill the pipe with antifreeze and place a cap on top. That way, the transducer will not freeze and crack.

TenMile
<'((((><

That's pretty much what I was told to do except for using vaseline inside the pipe. I think the antifreeze would work better or even mineral oil, but just make sure the transducer does not shift out of place in rough water.

 

[profisher]

Both my transducers are transom mounted and work to specs. One is a skimmer that i use for high speed sounding..it is in a fixed mount that will pop up if struck. My 1kw bronze Airmar($750) is also mounted on the transom, but on a home made stainless mount which allows me to lower and raise the ducer. At high speed I raise it up behind the bottom of the hull so it doesn't cause drag and can't be struck be debris. I also have an outboard on a bracket (pod)..so my props are not close to the ducers. I can lower the 1kw a foot below the hull while trolling if I want to. The bracket is a simple stainless tube with mounting flanges to bolt to the transom. Another stainless lube slides up and down inside the outer one...same as a long arm expendable downrigger boom. A handle is welded to the top and a ducer mounting flange to the bottom. A hole threaded through the outer takes a scotty downrigger bolt that acts as a set screw to lock it where you want it.

 

[knucklebuster]

after much frustration with losing my transducers to debris and having them lose bottom from turbulence I went through hull this past spring. Should of done it earlier.I talked to the folks at Chandler and they install them in a big gob of clear silicone. I did this and it works like a hot damn.28' boat and i'm tracking bottom (300-400') at 15 knots. never got that before.
Easy to move this way too if you've picked a bad location. Just slice the silicone and re goop.

a total MILF.Man I Love Fishing

 

[bigredsnapper]

Hey KB, did you use the standard transducer or a shoot thru hull. Where did you mount it? What sounder are you running and how much power. Thanks BRS

 

[knucklebuster]

quote:Originally posted by bigredsnapper

Hey KB, did you use the standard transducer or a shoot thru hull. Where did you mount it? What sounder are you running and how much power. Thanks BRS

its just the standard one that comes with the Lowrance X15
dual frequency.Of course its a replacement one as i must of hit something before and shattered crystal in original. I mounted it just about a foot off center(to avoid heavy glass down keel)and about 5 or 6 feet ahead of stern. Puts it just in front of starboard engine. I'm very pleased with its operation. Simple too. Did it one day while I was out at anchor. a couple of years ago i needed to replace the same one and hired a diver to do it(cheaper than hauling)on the transom. This is much easier and cheaper.

a total MILF.Man I Love Fishing