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5. If you are skilled with fiberglass, saturate a layer of fiberglass
cloth with a suitable resin and lay it inside the hole to seal and
strengthen the core. Add layers until the hole is the correct
diameter.
Alternatively, a hollow or solid cylinder of the correct diameter
can be coated with wax and taped 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 marine 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” and “Installing” (page 2).
Anti-fouling Coating
Surfaces exposed to saltwater must be covered with an anti-
fouling coating. Use
water-based
anti-fouling coating made for
transducers only. Never use ketone-based paint since ketones
can attack many plastics possibly damaging the transducer.
Brush on anti-fouling coating every 6 months or at the beginning
of each boating season.
Retractable Models: Coat the following surfaces
• Outside wall of the insert below lower O-ring and exposed end
• Bore of the housing up 30mm (1-1/4”)
• Exterior flange of the housing
• Blanking plug below the lower O-ring including the exposed end
Maintenance, Parts & Replacement
Cleaning
Aquatic growth can accumulate rapidly on the transducer’s face,
reducing its performance within weeks. Clean the surface with a
Scotch-Brite
®
scour pad and mild household detergent, being
careful to avoid making scratches. If the fouling is severe, lightly
wet sand the surface with fine grade wet/dry paper.
Retractable Models
Using the Blanking Plug
To protect the insert, use the blanking plug:
• When the boat will be kept in saltwater for more than a week.
• When the boat will be removed from the water.
• When aquatic growth buildup on the insert is suspected due to
inaccurate readings from the instrument.
1.
All the O-rings must be intact and well lubricated to make a
watertight seal.
On the blanking plug, inspect the O-rings
(replace if necessary) and lubricate them with the silicone
lubricant supplied or petroleum jelly (Figure 4).
2. Remove the transducer insert from the housing by removing the
safety wire and unscrewing the cap nut (Figure 2).
3. With the blanking plug ready in one hand, pull the transducer
insert most of the way out. Remove the insert and rapidly replace
it with the blanking plug. Seat it into place with a pushing twisting
motion until the key fits into the notch in the housing. With
practice, only 250ml (10oz.) of water will enter the boat. Screw the
cap nut in place.
Hand tighten
only. Do not over tighten.
D800, DT800
—Be sure the blanking plug is fully inserted into the
housing. Screw the cap nut several turns until the threads are
engaged. Continue to tighten the cap nut completely for a
watertight seal.
Hand tighten
only. Do not over tighten.
4. Reattach the safety wire to prevent the blanking plug from
backing out in the unlikely event that the cap nut fails or is
screwed on incorrectly.
Replacing the O-rings
All the O-rings must be intact and well lubricated to make a
watertight seal.
Inspect the spare O-rings and lubricate them with
silicone lubricant or petroleum jelly. Replace the O-rings.
Winterizing
After the boat has been hauled for winter storage, remove the
blanking plug to let the water drain away before reinserting it. This
will prevent any water from freezing around the blanking plug,
possibly cracking the plastic.
Replacement Transducer & 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 one.
Lost, broken, and worn parts should be replaced immediately.
Obtain parts from your instrument manufacturer or marine dealer.
Gemeco
USA
Tel: 803-693-0777
Email:
Airmar EMEA
Europe, Middle East, Africa
Tel: +33.(0)2.23.52.06.48
Email:
35 Meadowbrook Drive, Milford, New Hampshire 03055-4613, USA
www.airmar.com
