Transducer Placement

[Master4Med2]

Hello all,

I recently purchased a 5.1m Javelin Dory, used for coral trout fishing.
Because of the unusual hull shape, I’m looking for some suggestions on transducer placement ( Structure Scan and either a Airmar B60 or Airmar p66 )
From the drain plug going outboard to the starboard side, the first plank has a width of 200mm from the keel with a deadrise of 20 degrees, the second plank has a width of 250mm with a deadrise of 30 degrees.
Under the outboard step there’s enough depth to fit the LSS2 but not the P66.
As for the through hull B60, the only area it can go is plank no 1 but being so close to the keel I’m not sure if it will work.

Thanks' for any suggestions.

Con

[peterowen]

Hi Con

If you can put the through hull b60 with 20 degree fire about .5 metre forward of transom then this would be very good as will have no prop wash and you should track at higher speeds. However if placement impacts on a stringer do not install. I also noticed the rollers on your trailer will probably hit the transducer which for me the decision should be a transom mount. You cant put in number 2 as the angle is to high however you could install an fairing block which will cost allot extra but will work if a low profile is made.
The p66 is easier and put this on 2 in the very middle. There are lots of instruction on install on the net for this and on the bit of paper supplied with airmar gear. Make sure you install straight up and down not at angle of deadrise. Because of this large angle allot of the transducer on starboard side will be exposed to heavier water forces than on the port side. This can cause transducer to pop from bracket (not break) but then it flops around and can damage. There are two ways you can install the transom mount.
1. when installing the transducer the starboard side of transducer must not be to low to ground so that "the fin on the transducer (bottom of fixing bracket)" is below the bottom of hull level The transducer housing bracket must not be exposed to oncoming water as the flow may/will cause transducer to pop of bracket or produce to much turbulance. This will mean the port side of transducer will need to be just a 5 mm or so below keel. Drill holes mid way on transducer so you can adjust perfectly. Make sure you put sikoflex in screws hull so transom is water tight.
or
2 Install a tranducer slide assembly( I like the ally ones not stainless as easier to work with) available from most boating shops and then make sure bracket allows transducer to go only down only so far as what I said above ( if it goes to far then dont rescrew bracket just put a small stainless screw in bracket to limit how low it can go). Doing this will allow you to lift transducer when going full throttle. It also allows you to modify bracket to add another spare transducer, pumps, water pickups etc.However this is not practical if your transom is higher than the adverage 20 inch as you will not be able to reach it. However a bracket also produces some turbulence as its not flush with transom

Also if transducer is not low enough your fish finder will not track when you are on the plain due to bubbles from turbulence.

Hope this helps.

Cheers and good luck

PS Im in smithfield and work in industry. PM me if you like and arrange to pop around with boat and give you tips.

[Master4Med2]

G'day Peter,

Thank you for taking time to answer my question.
I will PM you later this afternoon.

Thank you

Con