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6. Installation
Cored fiberglass hull Follow separate instructions on chapter 6.5.
6.1 Hole Drilling
1. Drill a 3mm 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 from outside the hull.
3. Sand and clean the area around the hole, 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.
Metal hull Remove all burrs with a file and sandpaper.
6.2 Bedding
Apply a 2mm (1/16") thick layer of marine sealant around the lip of the
housing that contacts the hull and up the sidewall of the housing. The
sealant must extend 6mm (1/4") higher than the combined thickness of the
hull, washer(s), and hull nut (see Figure 4). This will ensure there is sealant
in the threads to seal the hull and to hold the hull nut securely in place.
marine sealant
Figure 4. Bedding and installation
insert
cap nut (plastic)
housing
safety wire
hull nut
washer
hull
Warning: Always wear safety goggles and a dust mask.