Follow the precautions below for optimal
product performance and to reduce the risk of
property damage, personal injury, and/or death.
17-008-06 rev. 0311/22/13
WARNING: Always wear safety goggles and a dust
mask when installing.
WARNING: Immediately check for leaks when the
boat is placed in the water. Do not leave the boat
unchecked for more than three hours. Even a small
leak may allow considerable water to accumulate.
CAUTION: Always operate the transducer in water.
Operating in air will allow the transducer to overheat
possibly resulting in failure.
CAUTION: The stainless steel housing must be
isolated from a metal hull to prevent electrolytic
corrosion. Use the isolation sleeve and washers
supplied.
CAUTION: SS422—The transducer must be oriented
properly. The mark on the face must be forward and
parallel to the centerline of the boat.
CAUTION: Never pull, carry, or hold the transducer by
the cable as this may sever internal connections.
CAUTION: Never strike the transducer.
Record the information found on the cable tag for future reference.
Part No.________________Date___________Frequency_________kHz
SS200
SS502
Tools & Materials
Safety goggles
Dust mask
Permanent marker
Electric drill
Drill bits and hole saws:
Pilot hole3mm or 1/8"
SS200, SS50223mm or 15/16"
SS42225mm or 1"
Sandpaper
Mild household detergent or weak solvent (such as alcohol)
File (installation in a metal hull)
Marine sealant (suitable for below waterline)
Knife or scissors (installation in a metal hull)
Slip-joint pliers
Grommet(s) (some installations)
Cable ties
Water-based anti-fouling paint (mandatory in salt water)
Installation in a cored fiberglass hull (see page 4):
Hole saws for hull interior:35mm or 1-3/8"
Cylinder, wax, tape, and casting epoxy
Mounting Location
Guidelines
CAUTION: Never use solvents. Cleaner, fuel, sealant,
paint, and other products may contain solvents that can
damage plastic parts, especially the transducer’s face.
IMPORTANT: Read the instructions completely
before proceeding with the installation. These
instructions supersede any other instructions in your
instrument manual if they differ.
Applications
Stainless steel transducer compatible with all hull materials.
Recommended for aluminum hulls to prevent electrolytic corrosion
provided the stainless steel transducer is isolated from the metal hull.
CAUTION: Do not mount in line with or near water intake or
discharge openings or behind strakes, struts, fittings, or hull
irregularities that will disturb the water flow.
CAUTION: Do not mount the sensor where the boat may be
supported during trailering, launching, hauling, or storage to avoid
damaging the transducer’s face.
• The water flowing under the hull must be smooth with a
minimum of bubbles and turbulence (especially at high speeds).
• The transducer must be continuously immersed in water.
• The transducer beam must be unobstructed by the keel or
propeller shaft(s).
• Choose a location away from interference caused by power and
radiation sources such as: the propeller(s) and shaft(s),
machinery, other echosounders, and other cables. The lower
the noise level, the higher the echosounder gain setting that
can be used.
• Choose a location with a minimal deadrise angle.
• Choose an accessible spot inside the vessel with adequate
space for the height of the stem and tightening the nut.
Page 2
Bedding
CAUTION: Be sure all surfaces to be bedded are clean and dry.
• Displacement hull powerboat—Locate amidships near the
centerline. The starboard side of the hull where the propeller
blades are moving downward is preferred.
• Planing hull powerboat—Mount well aft near the centerline and
well inboard of the first set of lifting strakes to ensure that it is in
contact with the water at high speeds. The starboard side of the
hull where the propeller blades are moving downward is preferred.
Outboard and I/O—Mount just forward and to the side of the
engine(s).
Inboard—Mount well ahead of the propeller(s) and shaft(s).
Stepped hull—Mount just ahead of the first step.
Boat capable of speeds above 25kn (29 MPH)—Review
transducer location and operating results of similar boats before
proceeding.
• Fin keel sailboat—Mount to the side of the centerline and
forward of the fin keel 300–6 00 mm (1 – 2').
• Full keel sailboat—Locate amidships and away from the keel
at the point of minimum deadrise angle.
Identify Your Model
The model name is printed on the cable tag.
SS422—To aid orienting the transducer, use a permanent marker
to draw a mark on the stem in line with the mark on the face (see
Figure 2).
Installation
Hole Drilling
Cored fiberglass hull—Follow separate instructions on page 4.
1. Drill a 3mm or 1/8" pilot hole perpendicular to the waterline from
inside the hull (see Figure 3). If there is a rib, strut, or other hull
irregularity near the selected mounting location, drill from the outside.
2. Using the appropriate size drill bit or hole saw, cut a hole from
outside the hull. Be sure to hold the drill plumb, so the hole will
be perpendicular to the water surface.
3. Sand and clean the area around the hole, inside and outside, to
ensure the marine sealant will adhere properly to the hull. If there
is any petroleum residue inside the hull, remove it with either a mild
household detergent or a weak solvent (alcohol) before sanding.
Metal hull—Remove all burrs with a file and sandpaper.
2
1. Remove the hull nut (see Figure 3).
2. Apply a 2mm (1/16") thick layer of marine sealant to the surface
of the transducer that will contact the hull / washer and up the
stem. The sealant must extend 6mm (1/4") higher than the
combined thickness of the washer, the hull, the second washer,
and the hull nut. This will ensure there is marine sealant in the
threads to seal the hull and hold the hull nut securely in place.
Metal hull—The stainless steel housing must be isolated from
the metal hull to prevent electrolytic corrosion. Use the isolation
sleeve and washers to separate the transducer stem from the
hull. However, the top of the isolation sleeve must be below the
hull nut after it is screwed into place, to prevent the sleeve from
interfering with tightening the nut. Slide the isolation sleeve over
the bedded transducer stem as far down as possible. Trim the
isolation sleeve to length. Apply a 2mm (1/16") thick layer of the
marine sealant to the outside of the isolation sleeve.
Installing
1. Slide a washer onto the cable and stem of the transducer. Rest
the washer against the transducer (see Figure 3).
2. From outside the hull, thread the cable through the mounting
hole. Then push the stem of the transducer through the hole
using a twisting motion to squeeze out excess sealant.
SS422—Orient the transducer, so the mark on the face and the
corresponding mark on the stem are forward and parallel to the
centerline of the boat (see Figure 2).
3. From inside the hull, slide the second washer and the hull nut
onto the cable. Rest the washer against the hull. Screw the hull
nut in place against the washer. Tighten the hull nut with slipjoint pliers.
SS422—Be careful not to rotate the housing disturbing the
alignment. When grasping the stem, be careful not to damage
the threads.
Metal hull—Be sure the isolation sleeve is between the
transducer stem and the hull. However, the top of the isolation
sleeve must be below the hull nut to prevent the sleeve from
interfering with tightening the hull nut.
Cored fiberglass hull—Do not over-tighten, crushing the hull.
Wood hull—Allow for the wood to swell.
4. Remove any excess marine sealant on the outside of the hull to
ensure smooth water flow under the transducer.
mark
NOTE: Orient the mark on
the face and the mark you
have drawn on the stem
CAUTION: If the sensor came with a connector, do not remove it
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 supplied. Removing the waterproof connector or
cutting the cable, except when using a water-tight junction box,
will void the sensor warranty.
1. 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 to prevent chafing. To reduce
electrical interference, separate the transducer cable from other
electrical wiring and the engine. Coil any excess cable and
secure it in place with cable ties to prevent damage.
2. Refer to the instrument owner’s manual to connect the
transducer to the instrument.
hull nut
hull
transducer
Checking for Leaks
When the boat is placed in the water, immediately check around
the transducer for leaks. Note that very small leaks may not be
readily observed. Do not leave the boat in the water for more than
3 hours before checking it again. If there is a small leak, there may
be considerable bilge water accumulation after 24 hours. If a leak
is observed, repeat “Bedding” and “Installing” immediately (see
page 2).
marine
sealant
marine
sealant
isolation
sleeve
3
Page 4
Installation in a Cored Fiberglass Hull
The core (wood or foam) must be cut and sealed carefully. The
core must be protected from water seepage, and the hull must be
reinforced to prevent it from crushing under the hull nut, allowing
the transducer to become loose.
CAUTION: Completely seal the hull to prevent water seepage into
the core.
pour in
casting
epoxy
dimension equal to
the thickness of the
hull’s outer skin to
ensure adequate
clearance
inner skin
core
1. Drill a 3mm or 1/8" pilot hole perpendicular to the waterline from
inside the hull (see Figure 4). If there is a rib, strut, or other hull
irregularity near the selected mounting location, drill from the
outside. (If the hole is drilled in the wrong location, drill a second
hole in a better location. Apply masking tape to the outside of the
hull over the incorrect hole and fill it with epoxy.)
2. Using the appropriate size drill bit, cut a hole from outside the
hull through the outer skin only. Be sure to hold the drill plumb,
so the hole will be perpendicular to the water surface.
3. The optimal interior hole diameter is affected by the hull’s
thickness and deadrise angle. It must be large enough in
diameter to allow the core to be completely sealed.
Using the appropriate size drill bit for the hull interior, cut through
the inner skin and most of the core from inside the hull keeping
the drill perpendicular to the hull. The core material can be very
soft. Apply only light pressure to the drill bit after cutting through
the inner skin to avoid accidentally cutting the outer skin.
4. Remove the plug of core material so the inside of the outer skin
and the inner core of the hull is fully exposed. Sand and clean
the inner skin, core, and the outer skin around the hole.
5. Coat a hollow or solid cylinder of the correct diameter with wax
and tape it in place. Fill the gap between the cylinder and hull
with casting epoxy. After the epoxy has set, remove the cylinder.
6. Sand and clean the area around the hole, inside and outside, to
ensure that the sealant will adhere properly to the hull. If there is
any petroleum residue inside the hull, remove it with either mild
household detergent or a weak solvent (alcohol) before sanding.
7. Proceed with “Bedding” on page 2.
Anti-fouling Paint
Surfaces exposed to salt water must be coated with anti-fouling
paint. Use water-based anti-fouling paint only. Never use ketonebased paint since ketones can attack many plastics possibly
damaging the transducer. Reapply anti-fouling paint every 6
months or at the beginning of each boating season.
Aquatic growth can accumulate rapidly on the transducer’s
surface reducing its performance within weeks. Clean the surface
with a Scotch-Brite® scour pad and mild household detergent
taking care to avoid making scratches. If the fouling is severe,
lightly wet sand with fine grade wet/dry paper.
Replacement Parts
The information needed to order a replacement transducer is
printed on the cable tag. Do not remove this tag. When ordering,
specify the part number, date, and frequency in kHz. For
convenient reference, record this information on the top of page 1.
Lost, broken, and worn parts should be replaced immediately.
ModelHull NutWashers
SS200
SS502
SS42202-149-0109-1098-01
Obtain parts from your instrument manufacturer or marine dealer.