Airmar M42 - Manual (Page 4)

transducer
4
Installing the M172
M172 in Resin Housing with Fairing
1. After the stuffing tube is installed following the instructions that
came with it, apply a 2mm (1/16") thick layer of marine sealant to
each threaded rod. Secure each rod with a nut. The rods should
extend a minimum of 3 threads beyond the nut. Slide a stainless
steel washer and rubbery washer onto each rod (see Figure 8).
2. Insert the transducer into the housing and place the clamp bar
on top. Slide the threaded rods up through the housing and
clamp bar. Secure the assembly in place with a stainless steel
washer and nut. Tighten the nuts with a torque wrench using a
force not exceeding 12 N-m (10 ft.-lb.).
3. Slide the fairing onto the threaded rods. Position it against the
transducer assembly.
Caution : Never pull, carry, or hold the transducer by its cable as
this may sever internal connections.
4. Thread the transducer cable through the stuffing tube to the
inside of the hull. Allow a service loop in the cavity of the fairing
so there is no tension applied to the cable.
5. Apply a 2mm (1/16") thick layer of marine sealant to the surface
of the fairing that will contact the hull.
6. Place the entire assembly against the hull, pushing the rods
through the hull. With a person stationed inside the vessel,
position the backing block on the rods. Secure each rod with a
stainless steel washer and nut. Tighten the nuts with a torque
wrench using a force not exceeding 7 N-m (5 ft.-lb.).
7. Plug the mounting holes to minimize turbulence on the surface
of the transducer.Cut the foam plugs to length so that, each
plug will be recessed 5mm (3/16") below the surface of the
housing. Push the foam plugs into the holes. Use marine
sealant to fill each recess flush with the transducer’s surface.
8. Remove excess marine sealant on the outside of the hull and
fairing to ensure smooth water flow over the transducer.
9. Follow the instructions that came with your stuffing tube to seal
the cable.
10.Check for leaks (see “Checking for Leaks” on page 3).
M172 Tank Mount
11.It is recommended that the clamp bar be shortened and re-
drilled to accommodate two bolts. They will secure the
transducer to threaded stand-offs that are welded to the floor of
the tank (see Figure 9). Check for leaks (see “Checking for
Leaks” on page 3).
Figure 8. M172 installation in resin housing
fairing
plug (2)
hull
nut (2)
rubbery
nut (2) and
washer (2)
threaded
nut (2) and
washer (2)
washer (2),
housing
clamp
rod (2)
marine
sealant
backing
bolt (4)
plate
screw (2) transducer
clamp bar
(shortened)
nut (2)
tank
hull
Figure 9. M172 tank mount
AIRMAR ®
weld
block
AIRMAR ®
AIRMAR ®
TECHNOLOGY CORPORATION
35 Meadowbrook Drive, Milford, New Hampshire 03055-4613, USA
■ www.airmar.com
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