Observe the echosounder’s performance, and compare it to the
baseline. Look for a stable depth reading that is similar to the
baseline. If you are testing a fishfinder, compare the thickness and
intensity of the bottom trace.
If the performance is close to the baseline, this is a good mounting
location. Remember, energy is lost transmitting through the hull. If
the test reading differs markedly from the baseline, you will need
to find another location to install the transducer.
If there is no reading or it is erratic, the transducer may be
positioned over coring which is absorbing the acoustic energy.
Choose another location. If no other spot is available, check with
the boat manufacturer to be certain coring is present.
Installation
Marking and Cutting
Caution
: For optimal performance, the transducer must be
installed parallel to the surface of the water.
1. When you are satisfied that the location of the transducer is
optimal, place the tank
up-side-down
on the hull at the selected
mounting location.
Be sure the
tallest
side is nearest the
centerline (keel) of the hull
(see Figure 5).
Caution
: Do not mark or cut the shortest side of the tank.
2. M256—
With a carpenter’s level held against an
angled
side of
the tank, draw a level line
even
with the point of the “V”. Repeat
this process on the opposite side of the tank. Along the
tallest
side, connect the two lines. This will be your cutting guideline.
M260
—Holding a carpenter’s level
eve
n with the
top edge
of an
angled side of the tank, draw a level line. Repeat this process on
the opposite side of the tank. Connect the two lines along the
tallest
side. This will be your cutting guideline.
Warning
: Always wear safety goggles and a dust mask.
3. B
e sure
the
tallest
side of the tank is marked and will be closest
to the centerline (keel) of the boat when it is installed.If you
have marked the tank even with the point of the “V”,
be sure
your transducer is a model M256 only.
Cut the three sides of the tank along the guideline that you have
drawn. It may be necessary to further shape the tank to the hull
to ensure a liquid tight bond.
4. The tank is provided with a cork liner to reduce sound echoes.
After the tank has been cut, wrap the cork liner around the
inside
of the tank. Butt the sides of the liner along the center of
the tallest side. Note, there may be a gap between the edges.
Holding the cork liner 6mm (1/4") below the top of the tank,
trace the bottom edge of the tank onto the liner using a pencil
(see Figure 6).
5. Remove the cork liner from the tank. Cut the liner along the line
drawn.
Bonding the Tank
Warning
: Always wear safety goggles and a dust mask.
1. The hull surface to be bonded
must
be smooth and free of paint
or any other finish. If the surface is rough, use a disk sander to
smooth an area slightly larger than the tank.
Figure 4. Testing the transducer at the selected location
A
B
C
Figure 6. Fitting the cork liner—M260 shown
trace bottom
edge of tank
onto cork liner
cork liner
6mm (1/4")
below top
of tank
Figure 5. Marking the deadrise angle on the tank
even with
top
hull
edge
carpenter’s
bottom edge
level
gap
M260—draw
level line
even with
of tank
M256—draw
level line
point of “V”
of short side
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