Humminbird 998c SI - Manual (Page 17)

Installation - Gimbal Mount 7
Gimbal Mounting the Control Head
If you are gimbal mounting the Humminbird®, you can pre-assemble the unit
in order to plan the best mounting location.
In addition to the hardware supplied with your control head, you will need a
powered hand drill and various drill bits, various hand tools, including a Phillips
head screwdriver, a socket wrench and a flat head screwdriver, a marker or
pencil, safety glasses and dust mask, and marine-grade silicone sealant.
1. Place the control head into the gimbal bracket. Make sure that the
straight side of the gimbal arm is against the back side of the control
head.
2. Place a 1" (25 mm) diameter black washer on the gimbal knob and
then thread the knob and washer into the housing. Tighten the
gimbal knob to secure the control head to the mount. Repeat step 2
for the other side.
You can now place the control head in various locations to decide which is
best for mounting. Rotating the mounting bracket to the top of the control
head will allow for overhead mounting. The chosen mounting area should
allow for sufficient room so the control head can pivot through the full tilt
range and allow for easy removal and installation.
NOTE: You can drill the cable pass hole underneath the gimbal bracket, allowing
you to thread the cables through the knock-out holes in the mount; however, if
you cannot drill the hole directly under the mounting bracket, then you will need
to drill the cable pass hole behind the bracket, and will need to mount the hole
cover there instead.
NOTE: When drilling holes in fiberglass hulls, it is best to start with a smaller bit
and use progressively larger drill bits to reduce the chance of chipping or flaking
the outer coating. Fill all holes with marine grade silicone sealant.
NOTE: You must have underside access to the mounting location to pass the
cables through to the surface. Also, make sure that the mounting surface is
adequately supported to protect the control head from excessive wave shock and
vibration and provide visibility while in operation.
3. After the mounting location has been determined, loosen the gimbal
knobs and remove the control head from the gimbal bracket.
Washer 1
Gimbal Knob 2
Gimbal Bracket 3
1
2
3