Humminbird piranha 3 & 4 installation User Manual

1. Attach the Transducer Body to the Bracket using the

hardware shown below.

2. Tighten the Pivot Bolt just enough so the transducer

can rotate, but remain in a place when released.

3. Apply silicone sealant into the drilled mounting holes.

4. Align the transducer with the mounting holes and

attach with Phillips screws provided.

5. Tighten the Mounting Screws just enough so the

transducer can move vertically, but remain in a place
when released.

Correct transducer height and running angle settings are
needed to ensure best performance at all boat speeds.
Use the template provided (pg. O-15) to make the initial
setting for most boats. Some boat hulls require adjust-
ments beyond these settings for best performance at
all speeds.
1. Cut out the transducer templates from the Piranha

package printed template insert following the cutting
directions for your boat hull.

2. Adjust the height on the transom and the pivot bolt

angle to match guides on the template as shown.

3. Hand tighten the Pivot Bolt and Mount Screws at this

time. Ensure the height and angle have not changed.

The cable must be routed to where the control head will
be mounted. Consider the following:
•

The easiest method to get the cable into the boat
routes the cable over the transom. The most common
method drills a hole through the transom, above the
water line.

•

Once inside the boat, the cable routes through or along
internal conduits and channels.

•

Keep the cable as far away as possible from VHF radio
antenna and tachometer cables.

•

Do not cut, shorten or lengthen the transducer cable.

•

If the cable is too short, extensions are available at
your dealer or direct from Humminbird.

1. Run the cable over the transom or through a 16mm

(

⁵⁄₈

") hole drilled well above the water line.

2. If a hole was drilled, fill it with silicone sealant.

3. Secure the cable with clamps as shown. (Figure 6).

1. Insert the Mount Arms through the Base.

2. Secure the Mount Arms with the 4 screws provided.

Figure 4

Mounting Bracket

Star lock washers

Pivot 

Nut

Cable

Pivot Bolt 

¹⁄₄-20, #3 Phillips Drive

Transducer

Place on bottom of hull

Align with transom.

Cut and use for Fiberglass Hulls 

Fiberglass

Aluminum

Transducer
Guide

Transducer bottom

Hull

Cut and use for Aluminum

 Hulls

 

30mm

15mm

Figure 5

Templates supplied locating the transom bracket and
adjusting the transducer’s position.

Transducer

150mm

6"

Figure 6

Cable Clamps

Right Arm

Arm Screws, 4 #6 x 

⁷⁄₁₆"

Left Arm

Figure 7