Advertisement
isolation sleeve
backing
block
marine sealant on following (shown in red):
- transducer, extending above hull nut 1/4" (NOT surface that will touch water)
- fairing that contacts hull
- backing block that contacts hull
- hull nut that contacts backing block
- anti-rotation bolt including bolt head, extending above nut 1/4"
- anti-rotation washer that contacts backing block
- yellow triangular plug: fill hollow half way (NOT curved surface that will touch water)
1. Dry fit the transducer in the fairing. Thread the cables through
the large hole in the fairing and through the mounting hole in the
hull. Seat the transducer firmly within the recess in the fairing
(Figure 5 or 6). Be sure the arrow on the transducer points
toward the triangular recess in the fairing.
2. Slide the transducer with the fairing in place into the mounting
hole. Using the bolt hole in the fairing as your guide, drill a 3mm
(1/8") pilot hole through the hull for the anti-rotation bolt.
3. Using the appropriate size drill bit, hold the fairing in place and
drill a hole for the anti-rotation bolt.
4. Remove the assembly and cables from the mounting hole.
5. Sand and clean the area around both holes, inside and outside,
to ensure that the sealant will adhere properly to the hull. If
there is any petroleum residue inside the hull, remove it with
either mild household detergent or a weak solvent such as
alcohol before sanding.
Metal hull—Remove all burrs with a file and sandpaper.
Bedding the Transducer
CAUTION: Be sure the surfaces to be bedded are clean and dry.
1. Remove the transducer from the fairing.
2. Apply a 2mm (1/16") thick layer of marine sealant to the surface
of the transducer that will contact the fairing and up the stem
(Figure 5 areas in red). The sealant must extend 6mm
(1/4") higher than the combined thickness of the fairing, hull,
backing block, and hull nut. This will ensure there is marine
sealant in the threads to seal the hull and hold the hull nut
securely in place.
Stainless steel transducer in a metal hull—To prevent
electrolytic corrosion, the stainless steel housing must be
isolated from the metal hull. Slide the isolation sleeve over the
bedded transducer stem as far down as possible (Figure 6).
Apply a 2mm (1/16") thick layer of the marine sealant to the
outside of the sleeve.
4
stem
hull nut
SS542
Figure 6. Bedding and installing in a metal hull
Copyright © 2017 Airmar Technology Corp.
anti-rotation
bolt
nut &
washer
High-
Performance
Fairing
isolation sleeve
triangular plug
with curved
surface facing
outward
3. Apply a 2mm (1/16") thick layer of marine sealant to the
following surfaces:
• Fairing that will contact the hull
• Backing block that will contact the inside of the hull
• Hull nut that will contact the backing block
4. Thread the transducer cables through the fairing and seat the
transducer firmly within the recess. Be sure the arrow on the
transducer points toward the triangular recess in the fairing.
Installing the Transducer
1. From outside the hull, thread the transducer cables through the
mounting hole. Push the stem of the transducer (with the fairing
in place) into the mounting hole using a twisting motion to
squeeze out excess sealant (Figure 5 or 6). Be sure the arrow
on the transducer points forward toward the bow.
NOTE: The transducer must be FLUSH with the fairing. If it is
recessed more than 0.5mm (1/64") inside the fairing, you may
shim the transducer or carefully file/sand the fairing.
Stainless steel transducer in a metal hull—Be sure the
isolation sleeve is between the transducer stem and the hull
(Figure 6). However, the isolation sleeve must be below the
washer and hull nut to prevent the sleeve from interfering with
tightening the hull nut.
2. From inside the hull, slide the backing block onto the transducer
cables and stem, seating the backing block firmly against the
hull. Screw the hull nut in place, but do not tighten it at this time.
Bedding & Installing the Anti-rotation Bolt
CAUTION: Be sure the surfaces to be bedded are clean and dry.
1. Apply a 2mm (1/16") thick layer of marine sealant to the anti-
rotation bolt including the flange (Figure 5 or 6). The sealant
must be 6mm (1/4") higher than the combined thickness of the
fairing, hull, backing block, washer, and nut. This will ensure that
there is marine sealant on the threads to seal the hull and hold
the nut securely in place.
►
BOW
NOTE: Be sure
the arrow on the
transducer
points forward
toward the bow.
hull
Advertisement
