advice required fitting a depth sounder transducer

kingfisher69 · 17 May 2007, 20:43

I have recently purchased an 4m avon searider rib with a flooding hull and i intend fitting a depth sounder it is my intention to glass the transducer direct to the deck in a oil filled tube hence it will have to sound through the thickness of the deck plus the distance of the flooding hull approx 150mm does anyone know if the transducer will function correctly having to pass through the deck, the void in the hull and the keel good advice much appreciated

Hugh Jardon · 17 May 2007, 20:51

Quote:

Originally Posted by kingfisher69

I have recently purchased an 4m avon searider rib with a flooding hull and i intend fitting a depth sounder it is my intention to glass the transducer direct to the deck in a oil filled tube hence it will have to sound through the thickness of the deck plus the distance of the flooding hull approx 150mm does anyone know if the transducer will function correctly having to pass through the deck, the void in the hull and the keel good advice much appreciated

i did that in a boat of mine 10 yrs ago and i would not recommend using a tube, you are probably better just bonding the transducer to the hull using sikoflex but taking care not to get any air trapped

that should then work fine

Biggles · 17 May 2007, 21:03

Hugh,

Do think that will work through the flooding hull ? I once thought about that when I had my searider but didn't think it would work.

Maybe Sikaflex it in the flooding hull and run the cable up the back of the transom. That would keep it off the deck as well so it doesn't get kicked or stood on.

NR.

Downhilldai · 17 May 2007, 21:23

Agree with Biggles - once you get the Searider up on the plane, the hull will empty and the transducer will be reading through a void, which will give poor soundings. The option of fitting it inside the hull is a good one, but it may be a difficult thing to fix in place - perhaps you'd be better just fixing it to the outside of the transom alongside the hole?

jwalker · 17 May 2007, 21:33

Kingfisher, do a search. Mounting depth transducers is a frequent question and it has been discussed many times.

Shooting through your empty hull will not work.

Nos4r2 · 17 May 2007, 21:42

Quote:

Originally Posted by kingfisher69

I have recently purchased an 4m avon searider rib with a flooding hull and i intend fitting a depth sounder it is my intention to glass the transducer direct to the deck in a oil filled tube hence it will have to sound through the thickness of the deck plus the distance of the flooding hull approx 150mm does anyone know if the transducer will function correctly having to pass through the deck, the void in the hull and the keel good advice much appreciated

It won't work properly. The flooding hull doesn't lose all the air in there-you can hear water moving in there while at rest so there must still be an air gap.
As said before it won't work when you're moving either.

Stick it on the transom or inside the flooding hull and then it'll work.

What year is your sr4?

My old sr4 had a transom mounted transducer and it worked really well-even at 40 knots.

Biggles · 17 May 2007, 21:53

Mine worked well on the first chine up. The picture below shows the location. That was an old Navman transducer which was later replaced with an Eagle. Only downside was if you beached it it sometimes got knocked up.

kingfisher69 · 17 May 2007, 21:59

thanks for all your help guys it looks like its either transom mount or access the deck and fit direct to the outer skin inside the void mmmmm decisions decisions

Biggles · 17 May 2007, 22:03

Quote:

Originally Posted by kingfisher69

thanks for all your help guys it looks like its either transom mount or access the deck and fit direct to the outer skin inside the void mmmmm decisions decisions

Not too sure what you mean about access the deck.

I'd go for my suggestion of sikaflexing it in the void by putting your hand through the water outlet hole, then running the cable back out the hole and up over the top of the transom.

IBWET · 17 May 2007, 22:07

On my SR4, I managed to epoxy the round sender (after keying the hull)directly onto the planing pad accessed through the hole at the back.

I drilled a hole between the 4 seats passed the sender cable and the power up through a witches hat along with the power to the bilge pump I also managed to fit through the hole

Then round the side to the dash for switching.
Worked gggrreat!!!

Quote:

Originally Posted by kingfisher69

I have recently purchased an 4m avon searider rib with a flooding hull and i intend fitting a depth sounder it is my intention to glass the transducer direct to the deck in a oil filled tube hence it will have to sound through the thickness of the deck plus the distance of the flooding hull approx 150mm does anyone know if the transducer will function correctly having to pass through the deck, the void in the hull and the keel good advice much appreciated

Nos4r2 · 17 May 2007, 22:08

SO would I-though mine was a lowrance transducer mounted in exactly the same place as Biggles's

Nasher · 18 May 2007, 07:00

Quote:

Originally Posted by IBWET

On my SR4, I managed to epoxy the round sender (after keying the hull)directly onto the planing pad accessed through the hole at the back.

I drilled a hole between the 4 seats passed the sender cable and the power up through a witches hat along with the power to the bilge pump I also managed to fit through the hole

Then round the side to the dash for switching.
Worked gggrreat!!!

IBWET
Are you saying you had a bilge pump in your flooding hull?

Nasher.

IBWET · 18 May 2007, 07:54

Yep,

I used a whale water pump, I think designed to pump water out of taps in caravans it was about 6" long and cylindrical.

It sat loose in the space next to the depth sounder and shifted about the same as a good flowing tap. It had lasted/worked for 4 years prior to the boat being stolen and I was very pleased with the way it performed.

The Hose,I brought up through the drain hole in the hull next to the transom,then over the back. The hull was sealed,so the only water it shifted came from people getting out of the water and into the boat,as previously mentioned it was switched through the dash via the access between the seats it became the norm to empty the hull just prior to pulling a monoskier.

On thinking about it, this was all in fresh water I have no reason to believe it would be any different in the sea, be feel it I should mention it.

Quote:

Originally Posted by Nasher

IBWET
Are you saying you had a bilge pump in your flooding hull?

Nasher.

Hugh Jardon · 18 May 2007, 07:56

oops

when i meant fix it to the hull i was thinking of inside the void at a place somewhere where there are no battens or strengtheners that might impact the signal, i totally agree that having it above a flooding hull would not be good.

on a river orientated boat 10 years ago i used the tube and oil method and i think that is a bit of a waste of time on a rib and would not recommend it, just sikaflexing is better
however on my rib i have fixed the transducer to the transom as folks have said below

kingfisher69 · 20 May 2007, 10:22

back into boating after 20 years plus and i am a little rusty to say the least, just joined ribnet forum and posted question about fitting transducer to my SR4, the response to my question from many other ribbers was astounding looks like i have missed out on the comaradery from the boating fraternity for too many years. So huge thanks to all you great guys out there who posted replies many thanks it is very much appreciated .