Why would you want a trolling motor that mounts to your outboard engine?
Engine-mounted models require less space than other types of trolling motors. If you have a smaller boat and want to save deck space, you should definitely give them a thought.
They are also almost invisible, which makes them excellent on dual-purpose boats.
In this article, we discuss some key benefits and disadvantages of engine-mounted electric motors and try to come to a conclusion if they are a good idea.
Engine mount motors are some of the most compact trolling motors out there, taking hardly any deck space.
They don’t get in the way other types of trolling motors do, with significantly less clutter involved.
They attach to your outboard and are underwater any time the outboard engine is off. When you start to move fast and plane, the electric motor emerges above the waterline.
This helps avoid causing drag and slowing down your boat while using your gas motor.
Steering and Controlling Your Motor’s Speed
The speed is usually controlled through a wired remote.
Since the electric trolling motor is attached to your outboard, you steer it the same way. The advantage is simplicity.
Because engine mount motors are fixed to a heavier outboard, changing the thrust direction is slower and the available angle smaller than on bow mount or transom mount models.
This makes them less responsive and more difficult to maneuver.
Are They Easy To Hold The Boat On The Spot?
In windy conditions, it’s the bow of your boat that tends to get blown away in the wind.
That is one of the reasons why bow mount trolling motors are so popular.
With an engine-mounted electric motor, it’s difficult to make tighter turns, and it can be quite frustrating to get your boat to the exact place where you want to be.
No Autopilot or GPS Anchoring
Engine mount motors today don’t offer any GPS navigation or Spot Lock.
They are designed for small size and to minimize any drag potential.
The only thing you can control is the speed of your electric motor. The rest, like steering and trimming, you do indirectly through the tiller and trim adjustment of your outboard.
They Are Easy to Install on Most Outboards
Engine mount trolling motors are fixed with bolts to the outboard motor’s anti-ventilation plate.
The installation process is straightforward. You don’t have to modify your boat or add any brackets like it’s in the case of bow-mount and transom-mount models.
Before you buy the motor, you should check if the anti-ventilation plate is deep enough under the waterline. There should be a minimum of 13 inches of submersion for the trolling motor to function correctly.
The right depth of your trolling motor is absolutely vital to make sure your propeller stays submerged regardless of water and weather conditions.
You don’t want the propeller to get out of water in choppy waters or/and sucking in air from above the waterline when it is not deep enough. It will cause noise, loss of power and can shorten the life of your motor.
Trolling Motor Buying Tips
Engine mount motors can be quite expensive, so before you buy one, make sure you educate yourself to avoid a potentially costly mistake.
Below, we’ll discuss the most important questions you should ask yourself and important things to know before deciding which motor to buy.
1. How Much Thrust Is Enough for My Boat?
Thrust is the force that moves the boat through the water. It is measured in pounds (lbs) and gives you a rough idea of the motor’s performance.
A generally agreed rule is that for every 100 lbs you will need at least 2 lbs of thrust.
For example, if your boat weighs 4000 lbs, fully loaded, then you want 4000/100 * 2 lbs = 80 lbs of thrust for your trolling motor.
My advice is to get the most powerful motor you can. For a large boat, you will be much better off with a 100+ lb trolling motor that runs at 36V.
You will also want more thrust if you fish in areas with fast currents and significant waves. The last thing you want is for your boat to be underpowered.
Learn more in our thrust guide.
2. Calculate Your Battery Runtime
This is one of the most frequently asked questions, and depends directly on two things: the capacity of your battery and the current draw of your trolling motor.
Battery capacity is measured in Ampere hours or Ah and current draw in amperes (amps). If your battery has 100Ah capacity and your motor draws 20 amps of current, then you can calculate its run time by dividing 100/20 = 5 hours.
However, this is only a theoretical number because depending on the type of battery you use, you will never want to deplete it to 0% of capacity. For example, if you have a standard lead-acid battery, you should really only use 50-70% of its Ah capacity if you want to keep it in good shape.
The current draw of your motor depends on the speed you set it to and how heavy your boat is. If you use your trolling motor at lower speeds, you will have a significantly lower current draw and much longer run time.
Weather and water conditions will also affect how long your motor will run. It is harder to push a boat against the current, choppy waters, or into the wind, which means higher current draw and shorter run time.
3. Get Saltwater Motor For Offshore Fishing
Each trolling motor description should state clearly whether you can use it in saltwater. Saltwater is much more corrosive than fresh water and requires different materials.
Minn Kota saltwater motors are built with premium-grade alloys, coated with zinc, and painted with corrosion-resistant polyester paint.
It is important to note that if you use a freshwater trolling motor in saltwater, it will often void your warranty.
Engine Mount Motors: Who Makes Them?
Currently, there is only one manufacturer that is known for mass-producing engine-mounted trolling motors – Minn Kota. Their Engine Mount (EM) range offers thrust from 55 lb to 160 lb, which covers the most popular boat types.
Minn Kota Engine Mount Series
Freshwater EM models come in three different thrust levels and each of them requires a different voltage and battery bank:
- Minn Kota Engine Mount 55 lb (12V) – for boats up to 18 feet
- Minn Kota Engine Mount 80 lb (24V) – for boats up to 20 feet
- Minn Kota Engine Mount 101 lb (36V) – for boats up to 22 feet
All of the motors are equipped with Digital Maximizer, Minn Kota’s name for the variable speed controller. It gives you smooth control in forward and in reverse. The great thing about variable speeds is the efficiency, which lets you achieve longer run time on a single battery charge.
The motors are supported by a composite mount. Its role is to keep your motor firmly attached to the outboard’s cavitation plate.
Minn Kota Riptide EM for Saltwater Fishing
The Riptide EM Series is designed and built for saltwater use. These motors are much more resistant to corrosion:
- Minn Kota Riptide EM 55 lb (12V) – for boats up to 18 feet
- Minn Kota Riptide EM 80 lb (24V) – for boats up to 20 feet
- Minn Kota Riptide EM 160 lb (24V) – for boats up to 24 feet
As you can see, the most powerful model in the Riptide EM series offers a whopping 160 pounds of thrust at 24 volts.
The 160 lb model is not just one but two electric motors mounted together side-by-side.
Such a setup can easily push heavy boats even in substantial winds and currents, making it especially suitable for fishing offshore.
Conclusion: Are They Worth It?
We recommend them only if you can’t or don’t want to install a bow mount model.
Engine mounted motors tend to be less maneuverable and lack the features present on premium trolling motors, such as GPS navigation.
On the other hand, we understand the appeal they have to some anglers.
If the engine mount is what you need, you won’t be disappointed with Minn Kota’s EM Series.