New Transducers B265LH, SS260, B271W SS258, B265LM, B258 User Manual

INSTALLATION INSTRUCTIONSOWNER’S GUIDE &

Thru-Hull, Depth with Stem

Transducer

Models: B45, B258, B260, B265LH, B265LM, B271W

SS258, SS260, SS270W, SS505

U.S. Patent No. 7,369,458. UK Patent No. 2 414 077. U.S. Patent Pending

Follow the precautions below for optimal
product performance and to reduce the risk of
property damage, personal injury, and/or death.

17-008-05 rev. 15 01/18/13

WARNING: A High-Performance Fairing must be
installed following the installation instructions that
accompany the fairing. A High-Performance Fairing
requires an anti-rotation bolt to keep the fairing from
turning while the boat is underway.

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: CHIRP transducer—Always operate the
transducer in water. Operating in air will allow the
transducer to overheat resulting in failure.

CAUTION: Bronze transducer—Never mount in a
metal hull, because electrolytic corrosion will occur.

CAUTION: Stainless steel housing in a metal hull
requires using a Fairing Kit to isolate the stainless
steel transducer from the metal hull. Failure to do so
will cause electrolytic corrosion.

CAUTION: Never install a metal transducer on a
vessel with a positive ground system.

CAUTION: Never pull, carry, or hold the transducer by
the cable as this may sever internal connections.

CAUTION: Never strike the transducer.

CAUTION: Never use solvents. Cleaners, 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

• Bronze transducer recommended for fiberglass or wood hull only.

• 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.

Record the information found on the cable tag for future reference.

Part No.________________Date___________Frequency_________kHz

B45

Standard
Fairing

High-Performance

Fairing

Identify Your Model

The model name is printed on the cable tag.

Tools & Materials

Safety goggles
Dust mask
Electric drill
Drill bits and hole saws:

Pilot hole 3mm or 1/8"
B45, SS505 22mm or 7/8"
B258, B271W, SS258 30mm or 1-3/16"
B260, B265LH/LM, SS260, SS270W 33mm or 1-5/16"

Sandpaper
Mild household detergent or weak solvent (such as alcohol)
File (installation in a metal hull)
Angle finder (installation with a fairing)
Band saw (installation with a fairing)
Rasp or power tool (installation with a fairing)
Marine sealant (suitable for below waterline)
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)

Drill bits and hole saws for hull interior:

B45, SS505 35mm or 1-3/8"
B258, B271W, SS258 40mm, 41 mm, or 1-5/8"
B260, B265LH/LM, SS260, SS270W 42mm or 1-5/8"

Cylinder, wax, tape, and casting epoxy

About Fairings

Most vessels have some deadrise angle at the mounting location. If
the transducer is mounted directly to the hull, the sound beam will
be tilted to the side at the same angle as the deadrise. A fairing is
strongly recommended if the deadrise angle exceeds 10°. Made of
a high-impact polymer with an integrated cutting guide, an Airmar
fairing is safer and easier to cut with a band saw and shape with
hand tools than custom fairings.

• Orients the sound beam straight down by mounting the
transducer parallel to the water surface.

• Mounts the transducer deeper in the water for clean flow over
the transducer’s face.

• Airmar High-Performance Fairing has a long streamlined
shape, directing water around the transducer to minimize drag.
Performance is excellent above 15kn (18MPH). (To order see
“Replacement Parts” on page 4.)

1/3

LWL

(Load Waterline Length)

outboard and I/O

stepped hull

Figure 1.

Best location for the transducer

Copyright © 2005 - 2010 Airmar Technol ogy Corp.

displacement hull

planing hulls

fin keel sailboat

full keel sailboat

pressure waves

150- 300 mm
(6-12")

inboard

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 (29MPH)—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 300–600mm (1–2').

• Full keel sailboat—Locate amidships and away from the keel
at the point of minimum deadrise angle.

Installation: No Fairing or Standard Fairing Only

IMPORTANT: If installing the transducer with NO fairing,

disregard all references to a fairing and backing block.

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 2). 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, 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.

Mounting Location

Guidelines

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.

• 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
headroom for the height of the stem and tightening the nut.

• CHIRP transducer—Mount in a cool well-ventilated area away
from the engine to avoid overheating.

Boat Types (see Figure 1)

• Displacement hull powerboat—Locate 1/3 of the way along
the LWL and 150–300mm (6–12") off 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).

2

Cutting the Standard Fairing

WARNING: High-Performance Fairing—For your safety it is
mandatory to follow the Installation Instructions that come with the
fairing.

CAUTION: The arrow/pointed end of the fairing points forward
toward the bow. Be sure to orient the fairing on the band saw, so
the angle cut matches the intended side of the hull and not the
mirror image.

1. Measure the deadrise angle of the hull at the selected location
using an angle finder (see Figure 2)

cable

stem

hull nut

backing block

isolation sleeve

fairing thickness

6– 12 mm (1/4–1/2")

Standard Fairing

transducer

Figure 2. Bedding and installing in a metal hull

(SS258 with Standard Fairing shown)

Copyright © 2005 - 2010 Airmar Techno logy Corp.

Aft View

hull

slope of hull

parallel to
waterline

marine
sealant

(metal)

deadrise
angle