Airmar B122—Long-Stem - Manual (Page 4)

4
marine
sealant
detail
Hole Drilling: Anti-rotation Bolt
Cored fiberglass hull—Follow separate instructions on page 7.
To locate and drill the hole for the anti-rotation bolt, use the fairing
as a guide. This will ensure that the hole is perpendicular to the
waterline and not drilled at the angle of the hull.
1. Dry fit the housing in the fairing. Seat the housing firmly in the
recess in the fairing (see Figure 6).
2. Slide the housing with the fairing in place into the mounting
hole. Hold the fairing parallel to the keel with the triangular
recess in the fairing is pointing forward toward the bow.
Using the bolt hole in the fairing as your guide, drill a 3mm or
1/8" pilot hole through the hull for the anti-rotation bolt.
3. With the 11mm or 7/16" bit and using the bolt hole in the fairing
as your guide, drill the hole through the hull for the anti-rotation
bolt.
4. Remove the assembly 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, (alcohol) before sanding.
Bedding the Housing & Fairing
CAUTION; Be sure the surfaces to be bedded are clean and dry.
1. Remove the housing from the fairing.
2. Apply a 2mm (1/16") thick layer of marine sealant around the
flange of the housing that will contact the fairing and up the
sidewall of the housing (see Figure 7). The sealant must extend
6mm (1/4") higher than the combined thickness of the fairing,
hull, backing block, and the hull nut. This will ensure there is
sealant in the threads to seal the hull and to hold the hull nut
securely in place.
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 hull.
- Hull nut that will contact the backing block
Installing the Housing & Fairing
1. Seat the housing firmly within the recess in the fairing (see
Figure 6). Align the notch in the top of the housing pointing
forward toward the anti-rotation bolt hole (bow).
2. From outside the hull, push the housing (with the fairing in
place) into the mounting hole using a twisting motion to
squeeze out excess sealant.
3. From inside the hull, Slide the backing block onto the housing.
Seat the backing block firmly against the hull.
4. Screw the hull nut in place. Do not tighten at this time.
Bedding & Installing the Anti-rotation Bolt
CAUTION: Be sure the surfaces to be bedded are clean and dry.
CAUTION: For smooth water flow under the sensor be sure the
external surface of the triangular plug is flush with the curved
surface of the fairing.
1. Apply a 2mm (1/16") thick layer of marine sealant to the anti-
rotation bolt including the flange (see Figure 6). The sealant
must extend 6mm (1/4") higher than the combined thickness of
Figure 7. Bedding the housing and fairing (B122 shown)
pull ring
safety wire
cap nut
hull nut
backing block
insert
housing
aft view
fairing
hull
sealant on flange, side wall,
fairing, backing block, hull nut
Figure 6. Bedding and installing the anti-rotation bolt (DST800L shown)
anti-rotation
bolt
nut &
washer
triangular plug
backing
block
fairing
curved surface
facing outward
hull
cap nut
(bronze/plastic)
Copyright © 2006 Airmar Technology Corp.
Copyright © 2006 Airmar Technology Corp.
BOW
►
NOTE: Notch
in housing
must face
forward toward
the bow