Depth Sounder...Hull or Transom??

[coolchange]

I am getting mostly wrong info from my old depth gauge and have to change that....the question is: should I not use a shoot-through and go for the more difficult install of a transom mount?

I seem to recall something about the hull construction on the 27 that might interfere with accuracy of a shoot-thru....I only need depth info (not fish finder stuff)

and last: any brands to love or to stay away from??

Thanks

[moses2015]

Using transom mount for my garmin 7400 series!,plus have hummingbird thro' hull for depth!,tried shooting thro hull,but not trusting readings?? hull to thick or cored??
See U in Desolation sound!!!or rivers INLET(sweetwaterII)

[sail149]

On other posts folks have reported good success with "shoot thru the hull" type on the centerline forward of the engine where the hull is solid fiberglass. The plastic tube bounded to the inner hull and filled with glycerine and setter in that tube produces the best signal vs gluing the sender to the hull.
Warren

[coolchange]

Hmmm "Glycerine and setter" sounds like another name for epoxy but I would like to know details of this new to me term....also how far forward does one need to go to get to "pure fiberglass" (no coring)...the current one is located at about the bow end of the engine..maybe 6" back from pulleys

[joebuz]

The PO had mounted a transducer (hole cut through hull) for the chart plotter aft the batteries on the port side of the engine. I wanted a depth sounder that could be used without always using the chart plotter. Used a "HawkEye" depth finder which can be mounted to shoot through the hull or on the transom. I followed their instructions to test the "through hull" capability. Found a spot next to the existing Garmin transducer (BTW, no interference). Stuck her there and (so far) it's been working great for the last year.

[Beta Don]

I used one of each. The boat came with a Furuno thru hull bronze removable tri-ducer (depth, temp and speed) already mounted on the port side of the engine aft of the battery platform - The hull is cored at that location. Since that bronze Tri-ducer is about $350, I decided to keep it and bought a used Furuno 'fishfinder' style unit which uses that Tri-ducer on eBay for less than $100. That was my back-up depth instrument - I've always had at least two depth instruments on very boat I've owned

The other was an Airmar P-79 transducer mounted on the keel just forward of the engine which was connected to my Garmin GPSMap760s - Access hole under the hanging locker was where I placed my transducer - The keel in that area is solid fiberglass about 1/2 inch thick - No coring. The P-79 has a base which you glue to the hull (I used 3M5200) and fill with Glycerine. That shoot thru the hull unit worked just fine at depths to at least 100 feet - I never went anywhere the water was deeper than 100 feet

I've never cared for transom mounted units - I prefer transducers to be mounted as far forward as practical. When I'm gunkholing in shallow water moving very slowly, I'd be ground before the transom unit gave me and advance warning

Don

[DCatSea]

Mazboot came with a Hummingbird 2000 THH and an older SiTex Sonar THH. The Hummingbird is no more, but the little SiTex gives depth readings that pretty much agree with the new transom-mounted Lowrance that provides us with all sorts of fairly useful information ( a good sign, I believe).

The transom mount for the Lowrance was not at all difficult, and so far hasn't leaked, fallen off or done anything untoward.

[kerrye]

I have an A25 so this may not be relevant but so far I took my Hummingbird transducer, put it in an old margarine container filled with anti-freeze, taped it up tight to avoid evaporation, put the container in the bilge with a zip lock bag with some sand on top of it. I did this to experiment with different locations for shooting thru the hull. I currently have it on the starboard side as near to the centerline as I can get just aft of the engine. Seems to be working fine there so far but I may also move it further forward.

[sail149]

Hi
"Glycerine and setter" I think should have been 'glycerine and sender'
Anyway I finally found a sketch of what I was talking about
The center sketch with glycerine In the tube is the ticket as it does not evaporate
I think a cap is a good idea. It's important to have no bubbles which a glued down version is tricky to do.
The clay dam idea is good as a trial idea to make sure it works.
Hope this gives you some ideas.
The text below suggests caster oil is the stuff to use.