Preparing the mounting location – Humminbird 1157C User Manual
Page 37
•
On boats with stepped hulls, it may be possible to
mount the transducer on the step. Do not mount the
transducer on the transom behind a step to avoid
popping the transducer out of the water at higher
speeds; the transducer must remain in the water for the
control head to maintain the sonar signal.
• If the transom is behind the propeller(s), it may be impossible to find an area clear from
turbulence, and a different mounting technique or transducer type should be considered, such as
an Inside the Hull Transducer (see Inside the Hull Transducer Installation).
• If you plan to trailer your boat, do not mount the transducer too close to trailer bunks or rollers to avoid
moving or damaging the transducer during loading and unloading of the boat.
• If high speed operation is critical, you may want to consider using an In-Hull transducer instead
of this Transom Mount transducer.
NOTE: The hydrodynamic shape of your transducer allows it to point straight down without deadrise
adjustment.
NOTE: If you cannot find a transom mount location that will work for your high-speed application, find an
In-Hull Transducer by contacting our Customer Resource Center at either 1-800-633-1468 or by visiting our
web site at www.humminbird.com.
2. Preparing the Mounting Location
In this procedure, you will determine the mounting location and drill two mounting holes, using the
transducer mounting bracket as a guide.
1.
Make sure that the boat is level on the trailer, both from port to starboard and from bow to stern, by
placing your level on the deck of the boat, first in one direction, then in the other.
2.
Hold the mounting bracket against the transom of the boat in the location you have selected.
Align the bracket horizontally, using the level; make sure that the lower corner of the bracket does
not protrude past the bottom of the hull, and there is at least 1/4" clearance between the bottom
of the bracket and the bottom of the transom for fiberglass boats, and 1/8" clearance for
aluminum boats.
Positioning the
Mounting Bracket
Level
Level
Boat Hull Types Require
Different Mounting Positions
1/4” for fiberglass
1/8” for aluminum
Deadrise Angle
27