How Does a Trolling Motor Work?

Transom-mount trolling motors are perfect for small watercraft like this flatboat.
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Trolling Motor Overview

Trolling motors are electric motors that fishermen and others use when they want to move their boat around the water but make a minimum of noise while doing it. Trolling motors also allow users to operate them at slower speeds than they could with a standard fuel motor. This type of motor comes in a variety of shaft sizes, so trolling motors can be used on small and large boats.

The Power Source

Twelve-volt marine batteries provide the power that is needed to operate trolling motors. They are wired with a set of positive and negative wires. These wires are connected to the corresponding positive and negative terminals on the marine battery. Once connected, trolling motors draw their power from the batteries and will run until the batteries run out of charge, at which time they can be re-charged. Trolling motors are quieter than fuel-burning motors because they run off of electricity. The amount of power trolling motors have is called thrust, and the higher the thrust, the faster they go.

Using Trolling Motors

In most instances, trolling motors are mounted on the bow or stern of a boat of other watercraft. They can be placed there permanently or mounted on brackets that allow users to quickly take them on and off. Some trolling motors have handles on them that users manipulate with their hands to turn the motor left or right, frontward or backward. Other trolling motors have special foot controls. Some of these devices are plugged into the trolling motor and others are wireless, but both varieties allow users to steer the motor using only their feet. By applying pressure to the left side of the foot control, for example, users can make the trolling motor itself turn to the left.

On the Water

When the trolling motor is under power, a prop at the bottom of the motor spins through the water. This is how trolling motors propel boats and other watercraft. Whether trolling motors have a handle or a foot control, users can decide how much power to send to the prop. The more power, the faster the prop spins and the faster the boat or watercraft moves. Other factors that influence the speed of trolling motors are the length and number of blades on the prop, as well as weather conditions like wind and water conditions like waves. No matter what the conditions, though, the more water the prop pushes, the faster the boat moves.