After a few times on the water, I decided it would be very beneficial to have a fish finder/sonar to locate structure and bottom contours while out fishing.
So, I set out to research my options. My priorities (in order) were cost, size, and reliability. After speaking with my father, who has had great luck with his Lowrance unit, I decided on the Lowrance X-4. This unit is small in stature but has great features and even better affordability.
The big obstacles when installing a sonar unit into a kayak are power source and transducer mounting. To overcome the first obstacle, I purchased an inexpensive battery from my local battery store. This battery is a 12 volt, 5 amp hour battery. Simple and small. To complete the power source duties, I purchased an inexpensive dry box from Walmart that is actually designed to keep items dry when camping and boating. The battery fit inside this box perfectly. I drilled two tiny holes, just large enough to feed the 14 gauge wire through. I wired in the inline fuse provided by Lowrance and utilized a 2 wire quick disconnect harness designed for a small trolling motor that I picked up from my local marina for a few dollars. I also added a short section of pipe insulation just to keep the battery from sliding around within the box. This entire assembly is fastened to the inside hull of the kayak via some 3M industrial strength velcro. This allows me to remove the box assembly for transport and for taking the battery indoors for charging.
As for the transducer, I had narrowed its installation down to a few options. Lowrance actually offers a transducer scupper mount designed specifically for use in sit-on-top style kayaks. This remains an option for me should I run into future issues with my current setup. However, I’m leery of this option due to the exposure of the transducer versus the shape of the bottom of my Angler 144. I would pretty much have to remove the transducer each time I beached and transported the kayak. Additionally, the wire to the transducer would be exposed on top of the kayak and could potentially become a nuisance trying to avoid while fishing. So, I chose the popular duct seal, shoot-through-hull setup. Duct seal is simply a strong putty-like substance used to seal junction boxes in walls. This is found in one pound blocks at your local hardware store in the electrical supply aisle. I picked my block up for less than $2. To use, just tear off a chunk, roll it tightly into a ball roughly the size of a golf ball. Press this ball into the bottom of the transducer, then press the transducer/ball combination firmly into the bottom of the hull. That’s all there is to it. There is nothing permanent about this mount, so you can remove the transducer at will. However, it is very strong. I generally store my boat topside down on the PVC rack I built, and the transducer has never fallen from its location, even in the 90+ degree heat we’ve been having.
Finally, I needed to decide where to actually mount the head unit of my X-4. After tossing around a few options, I chose to mount it in the forward cup holder location. For starters, I wasn’t using this cup holder for anything. Additionally, the base of the pedestal mount fit perfectly into the bottom of the holder. The length of the pedestal mount also allowed for me to access the back of the unit enough to be able to remove the unit, but kept it mostly out of the way and unobtrusive when on the water. It almost appears to be flush-mounted when in place and is the perfect viewing angle when I’m seated and fishing. This really worked out beyond my expectations. Along with using Marine Goop to seal the bolt holes for the bracket, I ran a bead of the stuff around the bottom of the bracket itself. This should seal the large hole used by the main unit’s wiring harness to keep any water entering the inside of the kayak from above.