When selecting a transom mount location, consider the following for optimal performance:

For your sonar to operate properly, the transducer must be located in calm water. DO NOT mount the transducer behind strakes, rivet lines, struts, fittings, water intake, discharge ports, eroding paint, or anything that creates turbulence.

Mount the transducer as close to the center of the boat as possible.

DO NOT cut the transducer lead. (This voids your warranty.)

DO NOT mount the transducer in locations where it might be jarred when launching, hauling, trailering, or storing.

DO NOT mount the transducer in the path of the prop on single-drive boats. The transducer can cause cavitation that can degrade the boat’s performance and damage the prop. On twin-drive boats, mount the transducer between the drives, if possible.

NOTE: DO NOT mount the transducer behind strakes, struts, fittings, water intake or discharge ports, or anything that creates air bubbles or causes the water to become turbulent. The transducer must be in clean (non-turbulent) water for optimal performance.

Installing the Fishfinder 400C

Tool List (not included)—drill, 3/8" wrench or socket, 5/32" and 1/8" drill bits, masking tape, #2 Phillips screwdriver, and marine sealant.

To mount the transducer on a transom:

1.Position the transducer mount at the selected transom location. Make sure the transducer is parallel with the water line. Mark the center locations of each hole on the transducer mount.

2.Using a 5/32" bit, drill the pilot holes approximately 1"

(25 mm) deep at the marked locations. To avoid drilling the holes too deep, wrap a piece of tape around the bit at 1" from the point of the bit.

3.Apply marine sealant to the 5 x 30 mm screws. Attach the transducer assembly to the transom using the 5 x 30 mm screws. Adjust the transducer assembly to extend beyond the bottom of the transom approximately 1/8" (3 mm) on fiberglass hulls or 3/8" (10 mm) on aluminum hulls. Adjust the transducer assembly to be aligned parallel with the water.

4.Tighten the 10-32 locking nut until it touches the mounting bracket, and then tighten 1/4 turn more. (Do not overtighten.)

5.Place the first cable clamp on the transducer cable approximately one third of the distance between the transducer and the top of the transom.

Fishfinder 400C Owner’s Manual