Mounting Location
Placement Guidelines
CAUTION
: Do not mount the transducer in line with or near water
intake or discharge openings or behind strakes, fittings, or hull
irregularities that will disturb the water flow.
CAUTION
: Do not mount the transducer in line with trailer rollers
or bunks that may damage the transducer’s face.
Choose a Location
• Where the hull is flat or nearly flat, so the transducer beam will
be aimed straight down.
• Where the water flowing under the hull is smoothest with a
minimum of bubbles and turbulence (especially at high speeds).
• Where the transducer will be in contact with the water at all times.
• Where the transducer beam will not be blocked by the keel or
propeller shaft(s).
• In a cool well-ventilated area away from the engine to avoid
overheating.
• Away from interference caused by power and radiation sources
such as: the propeller(s) and shaft(s), other machinery, other
echosounders, and other cables. The lower the noise level, the
higher the echosounder gain setting that can be used.
• Where there is working space inside the vessel.
Hull Types
(Figure 1)
•
Displacement hull powerboats
—Locate amidships near the
centerline. The side of the hull where the propeller blades are
moving downward is preferred.
•
Planing hull powerboats
—Mount well aft and
well inboard of
the first set of lifting strakes
to ensure that the transducer will be
in contact with the water at high speeds. The side of the hull
where the propeller blades are moving downward is preferred.
Outboard and I/O
—Mount just forward of the engine(s).
Inboard
—Mount well ahead of the propeller(s) and shaft(s).
Stepped hull
—Mount just ahead of the first step.
Installation in a Welded Tank
Each hull is different. Professionally install the transducer
following accepted practices.
Installation in a Cavity
Pre-molded Cavity
If the boat has a pre-molded cavity in the hull to receive the
transducer, go to “Making a Faceplate”.
Making a Cavity
1. Using the template (page 4), cut along the “cutting line for hull
cavity“ (outermost line). Tape it to the hull at the selected
mounting location.
2. Cut a hole in the hull.
2
inboard
Figure 1.
displacement hull
Best location for the transducer
stepped hull
outboard and I/O
Copyright © 2006 Airmar Technology Corp.
3. Create a strong watertight cavity to hold the transducer.
Making a Faceplate
A faceplate is required to ensure the transducer is held within the
cavity when the boat is traveling at high speed.
1. Make a faceplate using a strong material suitable for below the
waterline such as 316 stainless steel or glass-fiber reinforced
epoxy FR4 or G10. The faceplate must be thick enough to fill the
lip of the transducer [6mm (1/4")] after marine sealant is applied.
2. Cut the opening in the faceplate using the template supplied.
Follow the “Transducer lip: cutting line for the opening in the
faceplate.”
3. Drill holes for the fasteners that will hold the faceplate securely
to the hull. Fasteners must be suitable for below waterline.
Dry Fitting
The transducer must be flush with the bottom of the hull for good
performance.
Dry fit the transducer in the cavity before installing.
1. Position the template (page 4) within the cavity. Tape it in place.
2. Using the appropriate drill bits, drill a hole through the cavity for
the cable.
3. From outside the hull, thread the transducer cable through the
hole in the mounting cavity (Figure 2). Push the transducer into
the cavity as far as possible.
Measure the gap between the face of transducer and the outside
of the hull (as if the transducer is flush to the exterior hull
surface). This will be the thickness of marine sealant that must
be applied to the cable side of the transducer, plus an additional
3mm (1/8") to fill any empty spaces.
Bedding & Installing
CAUTION
: Be sure the surfaces to be bedded are clean and dry.
1. To ensure that the marine sealant will adhere properly, sand the
area around the hole in the hull, inside and outside. On the
transducer, sand all the surfaces that will contact the hull. Sand
the lip of the transducer (Figure 2).
Do not sand the face.
Remove
all dust using a tack cloth.
Do not use alcohol on the transducer
.
Figure 2. Dry fitting
Copyright © 2021 Airmar Technology Corp.
cable
lip
transducer
hull
cavity
face
thickness of marine
to the cable side
plus
3mm (1/8")
sealant to be applied
of the transducer
to fill any empty spaces