fiberglass hull
plastic, bronze, or stainless steel housing
housing
hull nut
spacer
washer
hull
marine sealant on flange and
side wall of housing
Retractable Models
1. After the marine sealant cures, inspect the O-rings on the
transducer insert (replace if necessary) and lubricate them with
the silicone lubricant supplied. The O-rings must be intact and
well lubricated to make a watertight seal.
2. Slide the insert into the housing. Seat the insert into place with a
twisting motion until the key fits into the notch. Be careful not to
rotate the housing and disturb the marine sealant. Screw the
cap nut in place and
hand tighten
only. Do not over tighten.
D/DT800
—Be sure the insert 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.
3. Attach the safety wire to prevent the insert from backing out in
the unlikely event that the cap nut fails or is screwed on
incorrectly (see Figure 2 or 3).
Plastic housing
—Attach the safety wire to one eye in the hull nut.
Keeping the wire taut throughout, lead the wire in a
counterclockwise direction and thread it through one eye in the cap
nut, the pull ring/eye in the insert, the second eye in the cap nut,
and the second eye in the hull nut. Twist the wire securely to itself.
Metal housing
—Wrap one end of the safety wire tightly around
the housing and twist it together with the long end. Keeping the
wire taut throughout, lead the wire straight up and through the
eye in the cap nut. Loop the wire through the pull ring/eye in the
insert and twist it securely to itself.
Cable Routing & Connecting
CAUTION
: If your transducer 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 provided. 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 using cable ties to prevent damage.
2. Refer to the echosounder owner’s manual to connect the
transducer to the instrument.
Checking for Leaks
When the boat is placed in the water,
immediately
check around
the thru-hull 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).
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 housing to become loose.
CAUTION
: Completely seal the hull to prevent water seepage into
the core.
1. Drill a 3 mm or 1/8" pilot hole from inside the hull. 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.)
3
Figure 2. Bedding and installing
retractable insert
washer
hull
pull ring
safety wire
cap nut
hull nut
washer
hull
pull ring
safety wire
cap nut (plastic)
hull nut
marine sealant on flange and
Figure 3. Bedding and installing
flush housing
metal housing
transducer insert
transducer insert
housing
housing
Copyright © 2006 - 2010 Airmar Technology Corp.
side wall of housing
Copyright © 2006 - 2011 Airmar Technology Corp.
(B17 shown)
(P217 shown)
marine sealant on flange and
side wall of housing
stainless steel housing in a metal hull
(SS577 shown)
(plastic/metal)
(P319/B117 shown)
fiberglass or wood hull
fiberglass or wood hull
retractable insert
marine sealant on flange and
isolation
bushing
washer
sidewall of housing
cap nut
hull
safety wire
housing
insert
(plastic)
(metal)
hull nut
and isolation bushing where it contacts hull
