How to Install a Fish Finder? Tips & Techniques

Detecting fish movements, structures, and cover is easy with a SONAR device called a fish finder. Many get anxious about installing these electronics, but if you select the right fish finder here and follow the instructions in this guide, it will be a quick and easy task.

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Fish Finder Installation & Mounting Overview

Although all fish finders come with installation guides, these instructions are frequently overly scientific or confusing. Since there are different processes for different types of boats, it can also be tough to find the right way to do it. This guide provides instructions for all the most popular styles of fishing boats.

Things You’ll Need for Fish Finder Installation

Fish Finder Kit
Of course, the device itself is important, but the best fish finders also come with their own mounting, installation tools, and a template for marking the holes.
Fish Tape & Gloves
Pushing wires through a conduit from the dashboard to the battery requires fish tape and gloves to protect your hands.
Cordless Drill & Drill Bits
A clean-drilled hole with a properly sized bit is essential to mount a fish finder and get the wiring done correctly.
Masking Tape
If you’re drilling into fiberglass, you’ll want to cover the places you drill beforehand with masking tape to prevent cracks, chips, and lines in the hull’s coating.
Cable Ties & Cable Wraps
Once all the wires are in place, ties and wraps can help to bundle them together to keep them tidy and organized.
Shrink Tubing/Electrical Tape
Shrink tubing is good to cover the end of connections made by twisting with linesman’s pliers. These connections can also be covered with electrical tape, but it’s not as long-lasting.
Heat Gun
Shrink tubing has to be shrunk with heat, which is where the heat gun comes in. They can be expensive, so it might not be worthwhile unless you plan to shrinkwrap your boat for longer-term storage.
Inline Fuse Holder & Fuse Kit
Fuses are necessary to prevent overcurrent in the total circuit of a fish finder's wiring. Inline holders are in the middle of a wire instead of inside a device, making them easier to change when they go out.
Wire Stripper/Crimper
The classic method of creating splices is to strip the end of each wire with a stripper or crimper and then twist them together with linesman’s pliers.
Unit Mounts
Many manufacturers sell tailor-made mounts for their fish finders, but some third-parties like RAM and even DIY models are also available.
Transom Saver Block
These are fantastic for owners of aluminum and fiberglass boats who don’t want to drill holes into their boats. They are generally meant to be placed only once, however.

Installing Fish Finders on Boats, Kayaks, and Motors

How to Install Fish Finder on Fiberglass Boats

As mentioned above, you’ll need masking tape, and a transom saver will be a plus. Additionally, your hardware and drill will have to go fast to punch through quickly to spare damage.

How to Install Fish Finder on an Inflatable Boat

There will be no drilling through the hull of your inflatable boat. Depending on the model, there may already be gear mounts in the cockpit for fish finders. Otherwise, you may need to get an aftermarket bracket.

How to Install Fish Finder on a Pontoon Boat

You’re likely to need nuts, bolts, and washers. Make sure they’re stainless steel to prevent rust. You can remove the sides of the boat easily to get full access, and snake wires through.

How to Install Fish Finder on a Kayak

Kayaks like the Vibe Sea Ghost have space for a fish finder on a RAM ball mount. There’s also a hole for the transducer cable in the cockpit and space for the battery.

How to Install Fish Finder on Trolling Motors

Clamp the transducer to the trolling motor with a stainless steel clip. Wrap it around the motor housing and fasten it there. Make sure to leave slack for depth adjustment.

How to Install Fish Finder on an Aluminum Boat

A transom mounting plate can be used with a marine epoxy plate to install with no holes drilled in the boat. 100% silicone works for caulking and should last pretty much forever.

How to Install Fish Finders On Center Console

In-Dash Flush Mounted
Larger boats with room for displays over 7-inches can fit professional-grade fish finders that feature built-in GPS. They’re visible over the steering wheel and take up no additional space, although installation is more complicated.
Gimbal Mounted
Gimbal mounts have adjustable screws at key points to change the angle and height of the display. They typically install on gear plates quickly, and the whole unit comes off in one piece.
Third-Party Mounting
RAM or Kong Mounts are great for less expensive fish finders that don’t come with their own mounts. They can mount to any flat area, so they’re some of the versatile types of mounts.

Transducer Types & Cable Setup

Transom Mount Transducers
Place the transducer on the starboard side of the transom for improved performance. Wherever you see the cleanest water flow, that’s where the transducer should go. Make sure the transducer just skims the water and avoid placing it near through-hull fittings or lifting strakes to get the clearest signal and best results.
Through Hull Transducers
Inside the hull, use rubber gaskets to mark where the ducer will be and drill holes. Cut a hole from the outside with a saw. Clean the area around the hole and sand it clean. Feed the cable through from outside until all the cable is inside and then place the sensor in the hole.
In Hull Transducers
Find a clean spot in the bilge that won’t have any muck buildup. The closer it is to the centerline of the boat, the better. The range will be less through a fiberglass hull than other types. Use a strong waterproof epoxy and avoid air bubbles when placing the transducer.

Garmin vs. Humminbird vs. Lowrance Fish Finder Installation

How to install Garmin fish finders
Garmin fish finders are above all affordable and easy to use. Installation is as straightforward as it comes. However, your Garmin will likely have GPS built-in, so plan to do a full install with wires and fish tape. If your device has ClearVu as well as SideVu, make sure it has a clear shot on both sides. Garmin makes their transducers to mount anywhere, including a trolling motor. They also have mounting plates for damage-free transom installation and kits for flush-mounting near the captain’s chair, although many models come with a tilt-swivel mount for mounting on the side or a gear track.
How to install Humminbird fish finders
All Humminbird Side Imaging units come with transom-mount transducers, so that's the most common way to install them. They’re suitable for aluminum, fiberglass, and pontoon boats alike. Through-hull mounting won’t work for any Humminbirds that have Side Imaging, so the transom mount or possibly an in-hull installation will be the only way to go. If you’re going to use epoxy in the installation process, make sure it’s the two-part slow cure kind. It’s convenient to have all the installation equipment you need provided, which is what makes Humminbird fish finders so popular with anglers who prefer to have a one-stop shopping experience.
How to install Lowrance fish finders
Lowrance has been in the game for a long time, and it’s clear from inventions like their kick-up mounting bracket that will prevent damage if the transducer strikes an object. When mounting a Lowrance in-hull, make sure it remains flat and not angled in the bilge. Mounting it too high if it’s a transom mount will result in lots of clutter and interference on the display. The TripleShot transducers need to be mounted at the right angle. There’s usually a line in the middle of Lowrance transducers, and that line should be even with the bottom of the boat for the best results.

Conclusion

Fishfinders are a crucial piece of equipment for anglers who want to be strategic and reel in lots of fish. Installing a fish finder can be intimidating, but it can be accomplished with the right tools and knowledge of how and where to mount the transducer.

How To Install A Fish Finder