Airmar B122—Long-Stem - Manual (Page 5)

5
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.
2. Apply a 2mm (1/16") thick layer of marine sealant to the surface
of the washer that will contact the backing block.
3. Push the anti-rotation bolt through the fairing and into the hull.
4. From inside the hull, screw the washer (sealant side down) and
the nut onto the anti-rotation bolt.
5. Use slip-joint pliers to tighten both the hull nut and the anti-
rotation bolt. Do not over tighten crushing the fairing or hull.
Cored fiberglass hull—Do not over tighten crushing the hull.
Wood hull—Allow for the wood to swell.
6. Use marine sealant to over-fill the hollow in the yellow triangular
plug. Apply a 2mm (1/16") thick layer of marine sealant to the
three sides of the plug that form the triangle. The sealant will
hold the plug firmly within the fairing and fill any gap between
the anti-rotation bolt and the plug.
7. The yellow triangular plug fits one way only. Push the yellow
plug into the recess in the fairing until it is FLUSH with the
outside of the fairing. This will squeeze out excess sealant. If
necessary, tap it into place with a mallet.
NOTE: If the triangular plug is slightly recessed within the
fairing, use sealant to fill the gap. The plug must be flush with
the fairing for good performance.
8. When the boat is underway, especially at high speeds, water
will enter gaps and push against the fairing with considerable
force. Fill any gaps between the fairing and the hull with marine
sealant. If there is any gap greater than 3mm (1/8”), replace
the fairing. Remove the excess sealant on the outside of the
fairing and hull to ensure smooth water flow under the sensor.
9. Continue with “Installing the Insert” on page 6.
Flush & Low-Profile Mount:
Suitable for All Models
Hole Drilling
Cored fiberglass hull—Follow separate instructions on page 7.
1. Drill a 3 mm or 1/8" pilot hole from inside the hull. If there is a rib,
strut, or other hull irregularity near the selected mounting
location, drill from the outside.
2. Using the appropriate size hole saw, cut a hole perpendicular to
the hull from outside the boat (see figure 8).
Flush housing—Use a countersink tool to make a ‘seat’ in the
hull.
3. Sand and clean the area around the hole, inside and outside, to
ensure that the marine 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 before sanding.
Bedding
CAUTION: Be sure the surfaces to be bedded are clean and dry.
Apply a 2mm (1/16") thick layer of marine sealant around the flange
of the housing that will contact the hull and up the sidewall of the
housing (see Figure 8). The sealant must extend 6mm
(1/4") higher than the combined thickness of the hull, washer, the
hull nut, and any adaptor ring. This will ensure there is sealant in
the threads to seal the hull and to hold the hull nut securely in place.
Adaptor ring—Slide the adaptor ring onto the housing. Apply
additional marine sealant to the surfaces of the ring that will
contact the hull, filling any cavities in and around the ring.
Installing
1. From outside the hull, push the housing into the mounting hole
using a twisting motion to squeeze out excess marine sealant
(see Figure 8). Align the notch in the top of the housing pointing
forward toward the bow.
2. From inside the hull, slide the washer onto the housing.
3. Screw the hull nut in place, being sure the notch is still
positioned forward toward the bow. Tighten with slip-joint pliers.
Cored Fiberglass Hull—Do not over tighten, crushing the hull.
Wood hull—Allow the wood to swell before tightening the hull nut.
4. Remove any excess marine sealant on the outside of the hull to
ensure smooth water flow under the sensor.
Figure 8. Bedding and installing without a fairing
flush mount low-profile mount with adapter
housing
hull nut
washer
hull
adaptor
Copyright © 2006 Airmar Technology Corp.
ring
B122 or DST800L B122 or DST800L
hull nut
washer
hull
marine sealant on
sidewall and flange
low-profile mount
ST700
marine sealant
housing
BOW
►
notch notch
notch