Raymarine Transducers, User Manual, Page: 28 / 56

22 Transducers for Fishfinders
Installation
Note:
To install the thru-hull transducer in a cored fiberglass hull,
follow the instructions in Installation in a Cored Fiberglass Hull on
page 29.
Drilling Holes
WARNING:
Always wear safety goggles and a dust mask when drilling.
1. Drill a 1/8" (3 mm) pilot hole perpendicular to the water line from
inside the hull (see Figure 2-3 ).
If there is a rib or strut near the mounting location, drill from the
outside.
If the pilot hole is drilled in the wrong location, drill a second hole
in a better location. Apply masking tape to the outside of the hull
over the incorrect hole and fill it with epoxy.
2. Cut a hole from outside the hull:
Fiberglass or wood hull – Use a 2" (51 mm) hole saw.
Aluminium or steel hull – Use a 2 1/8" (54 mm) hole saw to
accommodate the isolation sleeve used to prevent contact
between the stainless steel housing and the metal 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 a mild
household detergent or a weak solvent (alcohol) before sanding.
4. Remove one safety ring, the retaining pin, the cap nut, and the hull
nut from the transducer (see Figure 2-7 ).