Wanderlust World Wanderlust World Remove the boat from the water.
Determine the light's mounting location.
Drill a straight hole completely through the hull with a power drill. The hole size will vary with each particular thru-hull light. The light documentation will state the required hole size.
Apply marine epoxy to the inside of the hole surface and allow it to cure.
Apply marine sealant to the back of the light flange that will press against the outside of the hull.
Insert the light into its hole from the hull exterior.
Apply marine sealant to the back of the mounting not pressing against the inside of the hull, then tighten the nut with a wrench.
Attach the light wiring to a fused power source with a switch. The power source may or may not come with the light.
Remove the boat from the water.
Determine which trim tab will hold the light.
Position the light at the trailing edge of the trim tab and mark its screw holes.
Drill holes mounting holes through the trim tab. The hole sizes will vary according to the mounting screws for your particular light.
Fasten the light with machine screws, lock nuts and washers. These may come with the light. Use a screwdriver and wrench to tighten the nuts onto the screws.
Bend the trim tab down as far as it will go. Attach the light's power wire to the trim tab actuator with cable ties. This will ensure enough cable is available to facilitate the trim tab's full range of movement without stretching or pulling the cable.
Drill a straight hole completely through the hull above the water line with power drill. Position the hole right above the spot where the trim tab actuator attaches to the hull. A 5/16-inch drill bit will probably make a sufficient hole, but some lights may require larger holes, particularly if you run two wires through a single hole.
Insert the wire through the hull from the outside.
Apply marine sealant into the wire hole from the outside and inside of the hull. Smear the sealant around the wires with a gloved hand to create a good seal. Allow the sealant to cure.
Place the included clamshell cover over the hole opening on the outside of the hull, and drill its mounting holes into the hull.
Squeeze marine sealant into the screw holes before attaching the clamshell cover. Tighten its mounting screws with a screwdriver or socket.
Attach the light wiring to a fused power source with a switch. The power source may or may not come with the light.