Transducer Mounting

[MeMe]

I've just purchased a Garmin 100 Fishfinder which, will be used for depth readings only. My Medline has a strange transom / hull shape as it extends with what are termed as "planing trim flaps".

I could mount the transducer on these but experience shows that;

1. It looks crap as you have to make/buy a bracket for it to fit on.
2. Causes a fishtail.
3. Said fishtail also soaks the benchseat and occupants.
4. You buy a new transducer once a year as you inevitably catch it on the trailer / beach.

Therefore, I'm mounting it internally against the rear bulkhead.

My questions are;

1. Will this work?
2. Does the transducer need to face the same way as it does in the water because mounting it on the internal wall places it facing the wrong way ?
3. Does it need to be touching the base of the hull?
4. Does it need to be in water?

Tips and advice would be much appreciated, thanks.

[Phill]

Got my transducer in the bailing well of a Zodiac cherokee. Screwed the bracket to the forward wall of the well - so it's pointing the right way. Tighten it down roughly parallel to the waterline and leave an inch of water in the well (there always is anyway). Works fine up to 30 knots and 80 plus metres, have to slow to 20/22 for deeper. Occasional blip when its rough and the water sloshes, but not enough to warrent the glass a tube in and fill it with castor oil route.

[Pete7]

Did a temporary job on the club rib 5 years ago by glueing the transducer into the splash well with bathroom sealant. Still works today and it means ppl don't knock the transducer off when launching or beaching. Reception aokay up to 20 knots.

Also bonded a lowrance transducer into the hull of my Pacifc so it fire through the hull, loose a little performance but it works. Might do the same with the Garmin on this winter rather than have it mounted on the stern.

Pete

[jace]

Have a look at

http://rib.net/forum/showthread.php?...ansducer+epoxy

J

[tue]

When we fit transducers in the new Bayliner boats we use resin to bond them into the hull.

By making a mould using plastacine then filling with well mixed resin (so all air bubbles are expelled), we then place the transducer in the resin pointing the same way as if screwed to transom, and leave to set.

We have had no problems with this system, and its how mine are fitted, and it can be placed anywhere in the bilge/hull.

[jwalker]

Yeh, I agree with tue. My Garmin never lost the bottom at any speed when set like this. To prevent bubbles, run the resin down a stick to form a base. It may crack due to the heat. When this has set, run some more resin down the stick to slowly fill any cracks and make it about 3mm deep. Set the transducer into this. If you wax polish or apply release agent to the transducer, you can crack it loose at a later date if necessary. As security, I set a couple of bolts, facing up, into the resin also so that a clamp plate can be put across the top of the transducer to prevent it inadvertently being displaced.

[MeMe]

God I love this Forum. Thanks everyone, some really good tips.

[seafariskye]

I did it all as the instructions said -- epoxy it to the inside-- did that then it broke off, ( did not want it on the transom as it was a pain)

So,, i siliconed it to the inside, and it reads thro the hull - works fine, and no probs - one even reads thro black sikaflex..

Pete F

[wavelength]

yep - use the silicone in the drain well so youre sounding thru 1 layer. Follow Jaces link to the previous thread on this topic and youll see thats what we do-totally against the instruction book but it works just fine and you can get it out again if you sell the boat.

[Garygee]

Hi folks

I used silicone to mount my transducer in the engine bay, almost expecting to have to take it out ans use epoxy.

However it now done many miles and at any speed still gives good strong clear echos on my Lawrance X51.

Like Dave says it does work even if the books say not

Regards Gary

[MeMe]

After ummming and ahhhing over what cause of action to take I decided to go down the silicone route. I purchased a tube of B&Q bathroom sealant for £2.99 and produced a 2 inch bed on the inside of the hull just abaft of the bilge pump (after drying the surface of course). I positioned the transducer in this facing the right way (as if it was mounted on the stern) and left it to set.

Pleasingly I'm able to advise she works perfectly giving a depth reading at full speed and clear bottom - fish - structure display when trolling.

Once again thanks for all your advice and of course to the Forum.

Graeme.

[Windchill]

I've been following this thread with interest, as my transom mounted transducer, which sits just below the first spray rail, gives very poor readings. If I re-locate it in the deck sump, do I need to simply set its lower face in silicone, or completely encase it? Presumably Sikflex is avoided due to its permancnce?

[Pete7]

Windchill hi, yep we chose not to use sikaflex because as you say of its performance. Tried to take a seat out that had been glued in with the stuff and failed miserably. Ended up using an angle grinder. just put a smooth layer of sealant in the hull and push the sounder into it. The important bit is to ensure there are no air bubbles which can affect the sounder.

Read another good tip last night of putting the sounder in a plastic bag full of water. Place this in the hull with the boat in the water and see what the picture is like. If it shows a good picture then go ahead and glue. If not just move it to another area.

Pete

[gtflash]

what about the fls forward thinking transducers, i got one cheap but its supposed to be through hull... despite not wanting a 2" hole in my hull my boat has a deep v stepped hull, which means id need a huge block to straighten the transducer out and get it low enough to see past the front step. Any one had any experience of them?? how could i try it temporary in the hull? its supposed to dangle under the hull be about 1.5"

ta glen

[Windchill]

Thanks, will try silicone. If that works, perhaps something more permanent.

[wavelength]

Windchill
your extreme is the same hull as our ocean pro - our transducer was stuck onto a thin coat of silicone over 2 years ago and its still there despite very regular boat use-i dont think you will need anything more permanent!

[Windchill]

Transducer unit now relieved of its bracket etc. Fits in stern well nicely, but cable looks somewhat vulnerable. Any ideas.

[Windchill]

Bloody hell!! It works!! Good clear reading, no error messages, steady up to 30kts!

[juliano999]

As a rib novice I have read all this thread and intend to fit the transducer for my new lowrance M68i with silicon sealant to the inside of the hull. Am i right in thinking this should be fitted right in the middle of the v at the very back of the boat (zodiac yachtline 5m) and underwater.

[jwalker]

Put it slightly to one side in an area of hull which is smooth on the outside. You need there to be no turbulence, inducing air bubbles, on the outside of the hull.