3.If the decline in performance is sudden (not gradual), identify
the boat speed at which the onset occurred. Return the boat to
this speed, then gradually increase speed while making
moderate turns in both directions.
4.If the performance improves while turning to the side on which
the multisensor is installed, its position probably needs
adjustment. The multisensor is probably in aerated water.
To improve performance, try the following one at a time in the
order given.
A.Increase the multisensor’s angle in the water. Review
“Plastic Shims” and see Figure 5.
B.Move the multisensor deeper into the water in increments of
3mm (1/8") (see Figure 4).
C.Move the multisensor closer to the centerline of the boat.
Fill unused screw holes with marine sealant.
Stabilizing the Bracket
Stabilize the bracket by installing the third bracket screw at the
bottom of the center slot (see Figure 6). Using a 4mm, #23, or 9/64"
drill bit, drill a hole 22mm (7/8") deep. Toprevent drilling too deeply,
wrap masking tape around the bit 22mm (7/8") from the point.
Fiberglass hull—Minimize surface cracking by running the drill in
reverse until the gelcoat is penetrated.
Apply marine sealant to the threads of the third #10 x 1-1/4" self-
tapping screw to prevent water seepage into the transom. Tighten
the screw.
Cable Routing
CAUTION: Do not remove the connector to ease cable routing. If
the cable must be cut and spliced, use Airmar’s splash-proof
Junction Box No. 33-035 and follow the instructions provided.
Removing the waterproof connector or cutting the cable, except
when using a water-tight junction box, will void the sensor warranty.
Route the multisensor cable over the transom, through a drain hole,
or through a new hole drilled in the transom above the waterline.
1.If a hole must be drilled through the transom, choose a location
well above the waterline (see Figure 4). Check forobstructions
such as trim tabs, pumps, or wiring inside the hull. Mark the
location with a pencil. Drill a hole using the appropriate size bit
to accommodate the connector.
2.Route the cable over or through the transom.
3.On the outside of the hull, secure the cable against the transom
using the cable clamps. Position one cable clamp 50mm (2")
above the bracket and mark the mounting hole with a pencil.
4.Position the second cable clamp halfway between the first
clamp and the cable hole. Mark this mounting hole.
5.If a hole has been drilled through the transom, open the
appropriate slot in the cable cover. Position the cover over the
cable where it enters the hull. Mark the two mounting holes.
6.At each of the marked locations, use a 3mm or 1/8" bit to drill a
hole 10mm (3/8") deep. To prevent drilling too deeply, wrap
masking tape around the bit 10mm (3/8") from the point.
7.Apply marine sealant to the threads of the #6 x 1/2" self-tapping
screws to prevent water from seeping into the transom. If you
have drilled a hole through the transom, apply marine sealant to
the space around the cable where it passes through the transom.
8.If you have drilled a hole through the transom, apply marine
sealant to the space around the cable where it passes through
the transom. Push the cable cover over the cable and screw it
in place.
9.Route the cable to the instrument being careful not to tear the
cable jacket when passing it through the bulkhead(s) and other
parts of the boat. Use grommets where appropriate. To reduce
electrical interference, separate the multisensor cable from
other electrical wiring and the engine(s). Coil any excess cable
and secure it in place with zip-ties to prevent damage.
10.Refer to your echosounder owner’s manual to connect the
multisensor to the instrument.
3
Figure 6. Stabilizing the bracket
13°transom angle 14°–17°angle
Figure 5. Multisensor angle adjustment
20°transom angle3°transom angle
parallel slight angle
4.5° shim
4.5°shim
with taper
with taper up
angle
slight angle
9°shim
with taper
nearly parallel
May improve operation
above 20kn (23MPH) May improve operation
above 20kn (23MPH)
more angle
9°and 4.5°
shims with
more angle
May improve operation
above 20kn (23MPH)
down tapers down
down
May improve operation
above 20kn (23MPH)
4.5° shim
with taper
down
more angle
Copyright © 2004 Airmar Technology Corp.
Copyright © 2004, 2009 Airmar Technology Corp.
stabilizing
screw
