What Is a Trolling Motor?

What is a trolling motor? It is a small electric motor, powered by a battery, that moves a fishing boat slowly and quietly so you can hold a line along a weed edge, creep down a bank, or sit on a spot. On bigger boats it works alongside the gas outboard, which handles the run to the fishing area. On a kayak, canoe, or small jon boat it is often the only motor aboard. Most models clamp to the back of the boat or bolt to the front deck, and you steer them with a tiller handle, a foot pedal, or a wireless remote.

This guide is general product information, not repair or electrical safety advice. Follow the installation, wiring, and charging instructions in your product’s manual, stop using any battery, charger, or electronics that overheat, swell, or smell of burning, and contact the manufacturer.

This guide covers what the motor is, how it differs from an outboard, the main mount styles, the control options, salt water, voltage, and basic safety. Sizing the motor and measuring the shaft each get only a short summary near the end, because both deserve step-by-step treatment of their own.

What Is a Trolling Motor Made Of?

Every trolling motor has the same basic layout, top to bottom:

• Control head. The housing at the top holds the switch and, on hand-steered models, the tiller handle. Some heads also carry a battery meter.
• Shaft. A long tube that connects the head to the motor below the water and carries the wiring. Newport’s Kayak Series owner’s manual describes a fiberglass shaft, and the specifications in Garmin’s Force installation instructions also list the motor shaft as fiberglass.
• Lower unit and propeller. The sealed electric motor sits at the bottom of the shaft and spins the propeller directly. This part has to stay underwater to work.
• Mount. A clamp bracket for the transom, or a deck mount for the bow. A depth collar on the shaft lets you raise or lower the motor in the mount.
• Power leads. Cables that run to a battery or battery bank, usually through a circuit breaker.

Trolling motors are rated in pounds of thrust, not horsepower. Newport’s motor thrust guide explains that thrust is measured in pounds because it is a measure of static force, and that horsepower cannot be directly compared with it. The Newport manual makes a related point: speed depends on load, water conditions, hull type, and wind, so it gives thrust and power ratings instead of speed ratings.

How a Trolling Motor Differs From an Outboard

An outboard is built to cover water. A trolling motor is built to control the boat once you get there. The differences follow from that job:

• Power source. It runs on batteries, not fuel, and it is quiet enough to move close to fish without the noise of a gas engine.
• Speed and steering. It runs at slow, adjustable speeds and steers by turning the whole lower unit, which gives fine control in tight water.
• Intended use. Newport’s thrust guide states that its sizing recommendation is only for slower fishing use, not for a primary motor. On a boat with an outboard, the trolling motor is the second motor.

More thrust does not simply mean a faster boat. Newport’s trolling motor buyer’s guide notes that more thrust doesn’t necessarily mean more speed. Extra thrust mainly helps you push a heavier boat and hold against wind and current.

Mount Types: Bow, Transom, and Engine Mount

Bow Mount

A bow mount bolts to the front deck and pulls the boat from the front, which is why it is common on bass boats and other boats where one angler fishes from the front deck. The mount lets the motor fold up onto the deck for running and fold down into the water for fishing. Garmin’s Force installation instructions show what a bow install involves: that motor must go on the bow, as close to the boat’s centerline as possible, with the bumper overhanging the gunwale, bolted through the deck, and with room to swing between stowed and deployed positions. The same instructions say to verify that the deck is strong enough for the motor’s weight and force, and to add a backing plate or reinforcement if needed. Some owners add a quick-release bracket between the deck and the mount so the motor can come off the boat for storage.

Transom Mount

A transom mount clamps onto the flat back of the boat and pushes it. It is the simplest style to fit: tighten the clamp screws, set the depth, and connect the battery. The Newport manual walks through that sequence, including a tilt lever that swings the motor up out of the water and a collar for setting depth. Transom motors are common on jon boats, small aluminum boats, inflatables, and canoes with a square stern. Newport’s NV Series product page lists a standard transom mount for that line.

Engine Mount

A third, less common style attaches to the lower unit of the outboard itself, so the trolling motor turns when you turn the outboard. It suits boats with no room at the bow and no free space on the transom. Fit depends on the outboard, so check the trolling motor maker’s compatibility guidance before buying one.

Kayaks are their own case. Kayak motors usually sit on a stern or side mount made for that hull, and their short shafts are matched to how close the deck sits to the water.

How You Control One

• Tiller handle. You steer by swinging the handle and set speed by twisting it. On the Newport Kayak Series, the manual describes five forward and three reverse speeds on the twist grip, and warns against going from full forward to full reverse without letting the propeller stop first.
• Foot pedal. Common on bow mounts, it frees both hands for casting. Garmin’s Force owner’s manual describes a wireless foot pedal that pairs with the motor.
• Remote control. A handheld or wrist remote lets you steer from anywhere on the boat. Garmin’s guide to choosing a trolling motor says the Force Current and Force Kraken can also be controlled from a compatible Garmin smartwatch.
• GPS position hold. Higher-end bow mounts can hold the boat in place on their own. The Force owner’s manual describes anchor lock as an autopilot function that uses GPS to set and maintain your position with the trolling motor, acting as if you had dropped a physical anchor, and heading hold as a mode that keeps the boat on its current heading.

GPS features help, but they do not take over the boat. The Force owner’s manual reminds owners that they remain responsible for safe operation, that the controls should never be left unattended, and that the autopilot features should be learned on calm, hazard-free open water. Some bow mounts also carry a built-in sonar transducer in the lower unit, which puts a fish finder’s view right where the motor is pointing.

Fresh Water and Salt Water

Salt is hard on any motor, so check whether your maker rates the motor for salt water before you take it there. Newport’s trolling motor FAQ says its stainless steel and zinc hardware allow all of its motors to be used in salt water, and the NV Series page adds that the motors are saltwater compatible but not corrosion-proof. Garmin’s guide describes the Force Kraken as engineered for salt water.

Rinsing is part of the routine. The Garmin Force installation instructions tell owners to rinse the entire motor with fresh water after use in salt or brackish water, wipe on a water-based silicone spray, and avoid spraying jets of water at the shaft cap. The Newport manual asks owners to rinse only the parts that touched salt water and to keep the top cover dry, since water there can damage the circuitry. The two instructions differ, which is a good reason to follow the manual for the motor you own.

12, 24, and 36 Volts at a Glance

Trolling motors run at 12, 24, or 36 volts, and in the lineups below, the higher thrust ratings sit at the higher voltages. A 24-volt system usually means two 12-volt batteries, and a 36-volt system three:

• The Newport Kayak Series manual lists both kayak models (36 lb and 55 lb of thrust) at 12 volts and notes that Newport’s 86 lb model requires 24 volts.
• Newport’s buyer’s guide says its 112 lb motors require three 12-volt marine batteries.
• Garmin’s Force installation instructions require a 24 or 36 volt battery bank that can supply 60 A continuously.
• Garmin’s guide says the Force Current kayak motor delivers 30 lb of thrust on 12 volts or 50 lb on 24 volts.

Match the battery setup to what your motor’s manual specifies, and have the wiring done by the manual’s instructions or by a qualified marine installer, which Garmin recommends for its installs. Both makers call for a circuit breaker between the battery and the motor. For how long a single 12-volt motor runs on one charge, see the batteries and power section.

Basic Safety Around the Propeller and Battery

• The Force owner’s manual says not to run the motor with the propeller out of the water and not to use it where people in the water could touch the spinning propeller.
• The Newport manual says to disconnect power when replacing the propeller, clearing debris around it, charging batteries, transporting the boat, or leaving the motor unused, and not to let children operate the motor.
• The same manual warns that lead-acid batteries give off hydrogen and oxygen gas while charging, so sparks or flames near a charging battery can cause an explosion, and that the sulfuric acid inside can cause severe burns. It also tells users to always wear approved life jackets.
• If a battery swells, gets unusually hot, or smells burnt, stop using it and contact the battery maker.

Sizing and Shaft Length in Brief

Two numbers decide whether a motor fits your boat. The first is thrust: Newport’s rule adds the boat’s weight to its maximum load and suggests about 5 lb of thrust per 200 lb of that total, with more for wind, current, and chop. Working out how much thrust your boat needs takes a few more steps, including matching voltage to thrust. The second is shaft length, which has to keep the propeller underwater from your mount point, and measuring shaft length correctly depends on whether the motor goes on the bow, the transom, or a kayak mount.

Who Needs a Trolling Motor, and Who Can Skip It

A trolling motor earns its place if you fish structure from a moving boat, cast along banks, troll slowly for walleye or crappie, or fish from a kayak and want your hands free. It also makes sense on a small electric-only lake where gas engines are not allowed, if your state and the lake’s rules permit electric motors.

It isn’t for every angler. If you mostly anchor and fish one spot, drift with the wind, or fish from shore, a trolling motor adds batteries, wiring, and weight that you may not use. Anglers who paddle short distances on calm ponds can often skip it and put the money toward a fish finder instead.

Frequently Asked Questions

What is a trolling motor used for?

It is used to position and move a fishing boat slowly and quietly: following a shoreline, holding near cover, trolling lures at low speed, or keeping the boat in place against wind. On a kayak or small boat it can also be the only motor.

How does a trolling motor work?

Current from the battery runs through the power leads to the control head, where the speed control sets how much power reaches the sealed electric motor at the bottom of the shaft, and that motor turns the propeller. Newport’s performance and speed guide describes its transom motors as a motor head with a speed coil and propeller, connected to a control box with a speed switch, battery indicator, and control handle, and says top speed is limited by the voltage applied to the speed coil. You steer by pointing the thrust: the whole lower unit turns, by the tiller handle or, on many bow mounts, with a foot pedal or remote.

What kind of battery does a trolling motor use?

It depends on the motor’s voltage. Newport’s FAQ recommends a 12-volt, 50 amp-hour deep cycle or marine battery for its 12-volt motors and says it prefers lead-acid over lithium. Garmin’s Force needs a 24 or 36 volt bank that can supply 60 A continuously. Use the battery type and voltage your motor’s manual lists.

Can you use a trolling motor in salt water?

Only if the maker says so. Newport states that all of its motors can be used in salt water, and Garmin describes the Force Kraken as built for it. Either way, rinse with fresh water after each saltwater trip as your manual describes.

Does a trolling motor need a circuit breaker?

The makers in this guide call for one. The Newport manual recommends a manual reset circuit breaker in the motor leads, and Garmin’s Force instructions require a breaker rated for 60 A continuous. The Newport manual gives no rating, and Newport’s own pages give two: its trolling motor FAQ says the 86 lb motor is “rated for 50A” and recommends a 50 amp breaker for the 46, 55, and 86 lb motors, while its NV Series product page lists 60A for the 55, 62, and 86 lb versions. For a Newport motor, go by the label or paperwork that came with it, or ask Newport which rating applies. For other motors, use the rating in your manual. Follow your manual’s placement, or have a qualified marine installer do it.

Is a trolling motor the same as an electric outboard?

The terms overlap. Newport’s own manual calls its transom trolling motor an electric outboard motor. Rather than going by the label, compare thrust, voltage, shaft length, and the maker’s stated use, since Newport’s sizing advice, for example, assumes slow fishing use rather than a primary motor.

For how AnglerTechLab evaluates trolling motors and other gear, see How We Review, and browse the trolling motors section for related guides.

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