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The Ocean Kayak Trident 13 is made to install a fish finder. It has a custom fish finder bay with sun shield and a scupper hole with a recessed area made to accommodate a transducer. Within a week of purchasing my Trident 13 I began to install a fish finder.
The first thing I realized was that while the scupper hole was made to accommodate a transducer, it was not made to accommodate just any transducer. I had to ether needed to purchase a special scupper transducer, or make my own mount. As I could not find a scupper transducer to fit my fish finder, an inexpensive Garmin echo 100, and they are expensive anyway, I chose to make my own mount.
It was very easy.
Then drill two 1/4" holes in the aluminum, about 1/2" apart.
Next, take a long zip tie and place it on one of the holes. Set your kayak on its side, and put the aluminum over the scupper hole, with the zip tie going through the scupper.
To attach the transducer to the mount, simply thread the zip tie through the bolt holes on the transducer.
Now for the tricky part. Thread the zip tie back up the scupper hole and through the second hole in your aluminum plate. It helps if you have a very long zip tie.
Then just zip the whole thing closed.
My original thought was that this would be a temporary mount. I thought it might last long enough for me to devise a mount made of stainless steel bolts. However, it is amazingly secure. I have taken it out on dozens of trips without any problems. I think I will just continue to use this mount.
That is the hard part. All you have to do now is run the wires and mount the unit.
The Trident 13 has a groove in the fish finder bay that is probably for drainage, but works perfectly for running the transducer wire into the hull.
I recommend mounting the unit before you drill any holes to run cables. This way you will know exactly where you want things to go. The last thing you want to do is make unnecessary holes in your boat! Also, be sure you goop up any holes you make with silicone.
There will be quite a lot of excess cable. Bundle them up and zip tie them together. I hung them out of the way with zip tie mounts.
Run the power cable to the battery bag, and you are done!