Transducer swap

Nasher · 07 October 2007, 19:45

All

just thought I'd let you know the findings of a fishfinder transducer swap I tested today.

I've been a little dissapointed with the performance of the transom mounted transducer I fitted when I upgraded my electronics earlier in the year.

The old Garmin one was fine at moderate speeds, and only ever flipped up once when the RIB was beached.
The new Airmar(P66) one I fitted with my Raymarine digital FF flipped up on most trips and was very inconsistant at speed, although of course when it worked the digital FF was great.

I considered glueing the P66 inside the hull as others have done, but got the chance to do it properly with a P79 in hull jobbie.
Friday afternoon I bonded the housing into the hull right at the stern in the small bilge well I have, then Saturday I filled it with Castor oil and added the transducer itself.

Whilst mucking about in the harbour this morning before the cruise I took some soundings with the P66 the swapped the DSM connection over to the P79.

I got almost exactly the same depth recorded, and am very pleased to report that I did not loose the signal at all during the whole trip to Yarmouth and back. even at over 40 knots. There also didn't appear to be any differance in the quality of the data.

When I recovered the RIB at the Camber this evening, the P66 was of course pointing skyward despite the calm seas we had today.
Never again will I fit a Transom mount transducer or worry about the loss of data quality by shooting through the hull.

All I need to do now is remove the P66 and make good the mounting holes.

Nasher.

Tim M · 07 October 2007, 20:04

This is interesting, as mine doesn't work much above about 20 knots. I noticed today that the transducor on Merlin has been moved from the transom which is where Solent put them to the bilge well. Looks like I will have to add this to my winter to do list.

walruz · 07 October 2007, 22:37

Does anyone know if you can fit a through hull transducer in the inner hull of a sea rider?

Just a thought for winter tinkering.

Thanks

Ian

Hightower · 08 October 2007, 00:17

Does that mean I have to cut yet another hole in my Vipermax

Limey Linda · 08 October 2007, 00:27

Has anyone every removed a transom mounted tranducer and mounted it inside the hull and it worked OK ? Yes, I know how to do it.
Thanks.

Hightower · 08 October 2007, 00:41

Yes there where some threads about doing just that. Was some time ago, I guess if I wasn't so tired I would do a search

I think they encased the transducer in silkoflex or something.

Hightower · 08 October 2007, 00:45

Quote:

Originally Posted by Hightower

Yes there where some threads about doing just that. Was some time ago, I guess if I wasn't so tired I would do a search

I think they encased the transducer in silkoflex or something.

OK not so lazy:

http://rib.net/forum/showthread.php?...sducer+sealant

Limey Linda · 08 October 2007, 00:59

Quote:

Originally Posted by Hightower

OK not so lazy:

http://rib.net/forum/showthread.php?...sducer+sealant

Thanks Hightower, that was great. Really appreciate your effort.
From one lazy bugger to another.

Hightower · 08 October 2007, 01:10

Whilst still thinking for a name for the RIB, I did ponder "Bone Idle"

Apherel · 08 October 2007, 08:20

Hi Andy, Would the transducer fit into the small boxes at the rear of the Osprey? I was thinking it would be out of sight, out of trouble?

Navman have a (expensive) through hull transducer that is designed to fit on the hull angle, so that would get around the problem of needing to set it horizontally.

Hightower · 08 October 2007, 09:29

You can't put the transducer in the boxes because they're sited on the deck and the transducer needs contact with the hull.

As I understand it there should be no air between the transducer and the water (which includes air pockets in fibreglass) otherwise it won't work. This is why people use sealant or silkoflex to bed these down with.

Apherel · 08 October 2007, 09:59

Duh... Forgot about the deck, So that's why they are often mounted in the rear bilge/sump area. My current boat is open to the hull so it would be easy to mount.

So where/how do you fit one on the vipermax? Do you have to use an in-hull one if you don't want a transom mount?

Hightower · 08 October 2007, 10:05

I wouldn't mind a bilge mounted one, however I don't want to start cutting up me new Vipermax quite yet, so will opt for the transom one. The Navman one I had on my last boat was good and only once lifted up, this was because I must have hit something and that in turn smashed into the transducer, it still works as a transducer but the paddle wheel for the speed has broken off.

Nick Hearne · 08 October 2007, 10:23

Bit late now, but we had ours fitted under the deck then it was made!
Just sent it up to Osprey & they fitted it under the deck!