Humminbird 4086301, 4087301 3. Assemble and Mount the Transducer

4.Make sure that the drill bit is perpendicular to the actual surface of the transom, NOT parallel to the ground, before you drill. Using a 5/32” bit, drill the two holes only to a depth of approximately 1”.

NOTE: On fiberglass hulls, it is best to use progressively larger drill bits to reduce the chance of chipping or flaking the outer coating.

3. Assemble and Mount the Transducer

In this procedure, you will assemble the transducer using the hardware provided, then mount it and make adjustments to its position without locking it in place.

NOTE: You will initially assemble the transducer and the mounting bracket by matching the two ratchets to a numbered position on the transducer knuckle. Further adjustments may be necessary.

1a. If you already know your transom angle, refer to the chart below for the initial position to use to set the ratchets (Figure 16). If your transom is angled at 14 degrees (a common transom angle for many boats) use position 1 for the ratchets. In either case, go to step 2.

	Number	1	4		2	5	3	1	4	2	5	3	1
BeadgnmentAli
ranT	som Angle (°)
		-2 -1 0	1 2	3	4 5 6	7 8 9	10 11 12	13 14 15	16 17 18	19 20 21	22 23 24	25 26 27	28 29 30
asurM	ed Distance (x)	0.0 cm	.1cm		2.5 cm	4.3 cm	5.9 cm	7.6 cm	.3cm9	11.1cm	2.19cm	4.19cm	6.19cm
		0“	/2“1		1“	1 5/8“	2 3/8“	3“	3 5/8“	4 3/8“	5“	5 7/8“	6 5/8“

Figure 16

or...

1b. If you do not know your transom angle, measure it using a plumb line (weighted nylon string or monofilament line) exactly 12 inches long. Hold the top of the plumb line against the top of the transom with your finger, and wait until the line hangs straight down (Figure 17). Using a ruler, measure the distance from the bottom of the plumb line to the back of the transom, then use the chart (Figure 16).

NOTE: It is important to take your measurement in the location shown in Figure 17, from exactly 12 inches down from the top of the transom.

Transom Transducer Installation 12