4. INSTALLATION
28
Typical thru-hull mount transducer installations
Typical thru-hull mount transducer
installations
Procedure for installing the thru-hull mount transducer
1. With the boat hauled out of the water, mark
the location chosen for mounting the trans-
ducer on the bottom of the hull.
2. If the hull is not level within 15° in any
direction, fairing blocks made out of teak
should be used between the transducer
and hull, both inside and outside, to keep
the transducer face parallel with the water
line. Fabricate the fairing block as shown
below and make the entire surface as
smooth as possible to provide an undis-
turbed flow of water around the transducer.
The fairing block should be smaller than
the transducer itself to provide a channel to
divert turbulent water around the sides of
the transducer rather than over its face.
Construction of fairing block
3. Drill a hole just large enough to pass the
threaded stuffing tube of the transducer
through the hull, making sure it is drilled
vertically.
4. Apply a sufficient amount of high quality
caulking compound to the top surface of
the transducer, around the threads of the
stuffing tube and inside the mounting hole
(and fairing blocks if used) to ensure water-
tight mounting.
5. Mount the transducer and fairing blocks
and tighten the locking nuts. Be sure that
the transducer is properly oriented and its
working face is parallel to the waterline.
Note: Do not over-stress the stuffing tube and
locking nuts through excessive tightening,
since the wood block will swell when the boat
is placed in the water. It is suggested that the
nut be tightened lightly at installation and
retightened several days after the boat has
been launched.
Transducer preparation
Before putting the boat in water, wipe the face
of the transducer thoroughly with a detergent
liquid soap. This will lessen the time neces-
sary for the transducer to have good contact
with the water. Otherwise the time required for
complete "saturation" will be lengthened and
performance will be reduced.
DO NOT paint the transducer. Performance
will be affected.
Fairing
Block
Flat Washer
Rubber Washe
r
Hull
Deep-V Hull
H
ull
Flat Washer
Rubber
Washer
Flat Hull
Cork
Wash
er
BO
W
Hole for
stuffing tube
Upper Half
L
ower Half
Saw along slope
of hull.