NorthStar Navigation 491 - Manual (Page 13)

SECTION TWO — Installing the transducer
491 INSTALLATION MANUAL Revision A PAGE 9
FIGURE 4: Anti-fouling paint areas (for Airmar B744V)
Cleaning a
transducer
To clean the transducer of heavy debris or foul sea growth, use a stiff
brush or putty knife, but don’t scratch the surfaces. Check the transducer
every few weeks, maximum.
Use sanding sparingly, as repeated sanding may affect the transducer’s
performance at high speeds. For lighter cleaning, the surface may be
wet-sanded with #220 or finer wet/dry sandpaper.
CAUTION! Use special transducer paint. Other paints may
contain copper, which is conductive and can burn
out the transducer within minutes!
Anti-fouling paint (B744V shown)
Paint outside wall below the lower O-ring
including exposed end, paddle wheel cavity and paddle wheel
Paint exposed housing
lower
O-ring
and bore up 30mm (1-1/4")
paddle wheel
insert
housing
detail