Internal Mounting A Fish Finder On A Kayak

One of the most commonly asked question about mounting a fish finder to a kayak is “where or how do I mount it?” In this article Garry Fitzgerald who is well known for his involvement in the Sweetwater Fishing website, and the Wivenhoe Kayak and Canoe Fishing Convention takes us step by step through the mounting process.

Dirigo kayak

Some sit-on-top kayaks have specifically moulded scupper drains to accommodate the fitting of a transducer, while others will need to be able to mount the transducer internally, as will those paddling sit in kayaks. I wanted to fit a Humminbird to my Old Town, Dirigo Angler sit in kayak, so I asked myself the same question…where and how.

I firstly looked at what I wanted to achieve and what was available that would make the whole package come together easily and operate effectively. Looking at the cockpit of the Dirigo was the first step; what space was available for battery mounting, transducer mounting and finally mounting of the Humminbird head unit.


Head Unit Mounting


Railblaza mounting platforms

An adapter plate

My requirements for the Humminbird were that it had to be in a convenient location that allowed me to see the unit clearly, easily reach it to change settings, quickly to get out of the way if required and finally left nothing sitting above deck height to interfere when loading the kayak onto the roof racks of the car.

To mount the Humminbird head unit I decided to use the new Rail Blaza platform mount, attached under the deck to the bucket hatch in the dashboard. To marry the Rail Blaza mount to the Humminbird I used an adapter plate specifically designed for the job. This combination puts the fish finder in the best location. It is easily adjusted and folds away neatly inside the cockpit at the end of the day.

The Rail Blaza mount comes with bolts and screws to suit different fitting requirements. It can also be surface mounted or flush mounted making the system quite adaptable.

An adjustment knob on the side allows for fast and easy adjustments, while the lockable mount can be rotated to various positions.


Battery Mounting


A quality adhesive should be used for securing the battery tray in a kayak; you don’t want a wayward battery sliding about.[/caption]

I wanted the battery to be located out of the way of everyday fishing and paddling and yet still be able to access it when needed for trouble shooting on the water and to take the battery out for charging. Behind the seat in the Dirigo made an ideal location.

The battery I chose is a 12 volt 7 amp sealed type from Remco. It should be ideal for running a fish finder for 2 – 3 days of fishing without recharging.

The Railblaza base

To mount the battery I used a machined nylon material that comes with tie down strap for a secure fitting. I mounted the tray permanently into the kayak using Fix Seal, a 100% clear adhesive sealant that is suited to marine environments.


Transducer Mounting


The mounting process is clearly explained in the instruction manual that is included in the kit. It is important to ensure a clean surface before using any adhesive on a kayak and scuffing the surface also helps to give the adhesive something to grab onto.

Humminbird have released a transducer mounting kit for internal mounting in kayaks to take out the guess work and make the process quick and easy. The kit comes with everything you need to mount a transducer, including rubber boot with adhesive, scouring pad, Velcro hold down strap, alcohol wipe & primer to ensure a clean area before fixing the mount to the kayak. A tube of marine grade grease is also supplied and it is used to fill the boot and makes an air free pocket for the transducer’s signal to pass through.

Humminbird head unit

A sealed 7amp battery

A quality adhesive

A clean surface

The location chosen for the transducer was also behind the seat, next to the battery. In this case the wiring was run up the underside of the cockpit rails so is totally out of the sight and will not cause any obstruction. A few small blobs of Fix Seal can be used along the length of the cables to hold them in place. Excess cable can then be bundled up and zip tied off to the underside of one of the rod holders.

The transducer kit

Excess wiring

Well that’s it, sounder mounted. It’s important to do it properly, your sounder is your eyes under the water and you want it to be easy to use and operate effectively. Time to go fishing.

Dirigo 120 Angler kayak

The finished job with the Humminbird 385CXi mounted in the dashboard area of the Dirigo 120 Angler kayak, with battery and transducer mounted behind the seat.

Tools Used

Battery drill
Phillips head screw driver
Drill bits
Caulking gun
Products Used                                                                                                                    RRP
Old Town Dirigo 120 Angler kayak                      (BLA part 522448)                            $1499.00 Humminbird 385CXi Sounder / GPS Combo                                           (BLA part 102546)                            $799.00
Rail Blaza platform                                                  (BLA part 195652)                            $45.90

Transducer Mount Kit                                             (BLA part 103744)                            $59.50

Adapter Plate                                                            (BLA part 195800)                            $12.30

Battery Tray                                                               (BLA part 526222)                            $16.00

Sealed Battery 7amp                                               (BLA part 526216)                            $39.90

Author: Garry Fitzgerald