Humminbird 947C User Manual

Page 18

To mount the transducer pivot assembly to the bracket:

1. Slide the assembled transducer into the metal bracket from the bottom,

aligning the large hole at the top of the bracket with the hole in the pivot.

2. Insert the headed pin through the pivot holes in the bracket and pivot. The

headed pin can be inserted from either side of the bracket.

3. Place the nylon washer over the opposite end of the headed pin. Place the

stainless washer over the

¹⁄₄"-20 x ⁵⁄₈" screw threads, then insert into the

opposite end of the headed pin and finger tighten only. The screw has a thread
locking compound on the threads to prevent loosening, and should not be fully
tightened until all adjustments are made.

NOTE: The running position of the transducer is
now completely adjustable. Subsequent
adjustment may be necessary to tweak the
installation after high speed testing.

To adjust the running position of the transducer:

The transducer mounting bracket allows height and tilt adjustment, while the pivot
bolt allows angular adjustment. These adjustments will help reduce cavitation.
Initially, adjust the transducer as described in the following paragraphs. Further
adjustment may be necessary to refine the installation after high-speed testing.

NOTE: Your transducer may not look exactly like the transducer shown in the illustrations,
but it will mount in exactly the same way.

1. First, adjust the pivot angle of the transducer body, so it is parallel with the

length of the hull of the boat.

2. Fully tighten the two pivot screws, using the supplied Allen wrench. Access to

the pivot screws is provided by the lower holes in the side of the mounting
bracket. It may be necessary to re-tighten the pivot bolt after initial use as the
plastic may still be conforming to the pressure from the lock washers.

3. Adjust the height of the assembly so the face of the transducer is 1/8" (3 mm)

to 1/4" (6 mm) beneath the bottom of the transom, and fully tighten the three
mounting screws.

4. In order to gain access to the mounting screws, the transducer assembly must

be pivoted up in the bracket as shown. Be careful not to alter the running angle
as some force is necessary to pivot the assembly.

Normal Cavitation

Cavitation that will cause

erratic sonar readings

Headed Pin

Nylon Washer (fits over headed pin)

Stainless Washer (fits over screw threads)

Screw

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