Humminbird transducers are a key component of Humminbird fish finders. They work by emitting sonar beams into the water and interpreting the returning echoes to determine the presence, location, and size of fish, structure, and bottom contour. Proper transducer mounting is critical for obtaining accurate sonar readings. There are several factors to consider when determining where to mount your Humminbird transducer, including transducer type, hull type, speed, and interference.
Transducer Types
Humminbird offers three main transducer mounting options: transom mount, trolling motor mount, and in-hull mount.
Transom Mount
Transom mount transducers are the most common type. They mount to the exterior of the boat’s transom, extending down into the water. Transom mounts work well for aluminum and fiberglass hulls. They should be mounted as close to the center of the transom as possible, to avoid interference from the engine and maximize depth readings. Transom mounts are not ideal for planing hull boats, as the transducer will lift out of the water at higher speeds.
Trolling Motor Mount
As the name implies, trolling motor transducers attach directly to the trolling motor’s shaft or motor head. This positions the transducer in the perfect place to provide sonar readings at trolling speeds. Trolling motor mounts only provide limited visibility directly under the boat. They are best for dedicated trolling applications.
In-Hull Mount
In-hull transducers are epoxied inside the hull of the boat. They work well for fiberglass boats and provide unmatched speed capability. However, they do sacrifice some sensitivity compared to transom mounts. In-hull mounts require the transducer to shoot sonar beams through the hull, limiting the strength of the return echoes. They also provide limited visibility directly beneath the boat.
Hull Type
Hull type plays a big role in transducer mounting location. Here are some of the most common hulls:
Aluminum
Aluminum hulls are highly sonar-friendly, providing clean readings across a range of speeds. They work very well with transom mount transducers. For best results, the transducer should be mounted around 1/3 of the way back from the bow to the transom. This helps lift the transducer out of turbulent water flowing off the hull.
Fiberglass
Fiberglass hulls are also sonar-friendly. Transom mounts generally work well on fiberglass boats. In-hull mounts are an option for maximizing speed capability. With heavier deep v-hulls, a transom mount may need to be angled slightly to account for the deadrise angle.
Aluminum Pointed Bow Hulls
Pointed bow hulls create more turbulence and running angles than square bow designs. This can make transducer mounting more difficult. A jack plate can help improve transducer positioning and reduce interference on pointed bow aluminum boats.
Jet Boats
Jet boats eliminate the use of a lower unit. This improves transducer mounting options. But the turbulent discharge from the jet intake can cause interference. Mounting the transducer well forward, in front of the jet nozzle, provides the best readings.
Speed
Transducer mounting location also depends on the typical speeds the boat will reach. Here are some speed-based mounting considerations:
Slow Trolling Speeds
At very slow trolling speeds, less than 3 mph, transom mounts provide great visibility directly beneath the boat. Transducers can be mounted close to the centerline of the boat.
Faster Trolling Speeds
As speeds increase from 3-7 mph, transom mounts should be positioned further port or starboard. This moves the transducer out of the prop wash and reduces turbulence. Transducers can be angled slightly to improve water contact at faster trolling speeds.
Planing Hulls
Planing hulls getting up on plane above 15 mph require in-hull or transom transducers designed specifically for higher speeds. The transducer must be mounted in a location that stays in contact with the water at all speeds.
Step Hulls
Step hulls plane at multiple points, making transducer mounting tricky. Starting with an in-hull mount provides the most consistent readings across all speeds on step hulls.
Interference
Engine Interference
On outboards and stern drives, the transducer should be mounted a minimum of 15″ to the side of the propeller(s). This avoids interference from the engine lower unit and prop wash.
Turbulence
As mentioned above, turbulent water flowing off the hull can impact transducer performance. Getting the transducer mounted in clean water is key. Trim tabs, strakes, and other running surfaces can create unwanted turbulence if the transducer is mounted too close.
Bubbles and Air
Transducers emit sound waves, so bubbles and air interrupt clear readings. Areas of bubbly water from the engine exhaust or paddlewheel aeration systems should be avoided. Transducers mounted in these bubbles will struggle.
Boat Traffic
Wakes and interference from other boat traffic can influence transducer readings. While unavoidable at times, heavy boat traffic areas are not ideal transducer mounting locations.
Types of Mounts
There are several options available for mounting the transducer itself:
Transom Brackets
Transom mount transducers typically use a transom bracket that bolts to the transom. The transducer can then be adjusted vertically and angled to dial in the position. Transom brackets allow for adjustment over time as the boat ages.
Suction Cups
Many trolling motor transducers use a heavy duty suction cup mount. Suction cups provide quick, temporary installation without modifications to the motor. However, suction cups can lose grip over time. Some also have screw or bolt down options.
Epoxy
Permanent in-hull installations use an epoxy to adhere the transducer inside the hull. This provides the most secure bond. But it requires careful preparation and permanent modification to the boat. If the transducer ever needs to be relocated, a new epoxy mount must be installed.
Portable Mounts
Portable mounts allow transducers to be removed and stowed when not in use. Options like Tite-Lok clamps or O-ring mounts attach to the transom quickly. Portable mounts are typically less stable than permanent installations.
Best Practices
Here are some key best practices to follow when mounting your Humminbird transducer:
– Position the transducer as close to the centerline of the boat as possible
– Keep 15″ of clearance from the engine lower unit and propeller(s)
– Mount in an area with clean, smooth waterflow
– Avoid turbulence from strakes, trim tabs, and other running surfaces
– Consider a jackplate on pointed bow boats to improve mounting position
– For planing hulls, only use transducers designed for higher speeds
– Protect transducers from physical damage or impact
– Follow all mounting guidelines provided by the manufacturer
Proper installation combined with some testing and fine-tuning will provide the optimal transducer mounting location for your boat. Don’t be afraid to experiment with different positions to compare sonar readings. With a good mount location dialed in, your Humminbird fish finder will deliver excellent underwater views.
Frequently Asked Questions
What is the best transducer mounting height?
Ideally, transducers should be mounted so the face is 0.5-1″ below the bottom of the hull. This provides just enough depth to avoid turbulence from the hull while maintaining good signal strength.
Should transducers be angled or perpendicular?
Most transom mounts work best when the transducer face is angled slightly outward, around 1-3 degrees. This helps the sonar beam penetrate the water. Perpendicular mounts can work but may have decreased performance.
How do I get the transducer past the hull recess on my boat?
Using a transducer mounting block or wedge can help angle the transducer outward and lower it enough to get beyond the recess on boats with an inset transducer location.
Can I mount multiple transducers?
It is possible to mount more than one transducer on a boat, provided they are spaced adequately to avoid interference. However, most boats only need one transducer. Multiple transducers are seen more often on specialty commercial boats.
Does speed affect transducer mount location?
Yes, running speed has a major impact on transducer mounting position. Slower trolling speeds give more leniency while planing and step hulls running at high speeds require very strategic mounting locations.
Conclusion
Mounting your Humminbird transducer properly is crucial for getting great sonar readings. Consider the transducer type, hull material, typical speeds, and interference sources when choosing the ideal installation location on your boat. Follow best practices for installation and make small adjustments as needed. With the transducer dialed in, you’ll enjoy vivid underwater views and find more fish.
