Purchasing and Electric Motor

Never before have electric motors been as popular and affordable as they are today. But there are a number things to consider before jumping in buying any old electric motor. In this article I would like to address some of the things that need consideration when making this very important purchase. On many boats, an electric motor will be your most expensive accessory. So its worth getting right! But please, let it be said now, that I am not an electronics expert. I'm simply sharing my thoughts based on past experience.

Transom or Bow Mounting

The main outboard motor of a boat is located to stern and bolts to the transom. This motor 'pushes' the boat when the throttle is applied. Steering adjustments are made when the motor is turned left or right. It is possible to also mount electric motors to the transom of the boat also, although this is usually slightly to one side of the main outboard. In this situation steering becomes incredibly difficult. Generally speaking, steering from the transom becomes easier with speed, and electric motors will not be moving fast enough to make quick adjustments. I would only mount an electric motor in this position for general straight line trolling. It is not suitable for delicate adjustments needed for lure casting to snags.

Bow mount electric motors, on the other hand, are positioned on nose or 'bow' of the boat, as close to centre line as possible. In this position, the thrust of the electric is used to 'pull' the boat along. In this way the front of the boat is easily pulled left or right in a tight turn, the rest the boat just follows. This is by far the best method of mounting an electric motor for lure casting, but is still fine for trolling also.

On a slightly different note, I see a lot of people raise their outboard motor when under electric power. I would highly recommend not doing this unless you are running in shallow water and need the clearance. The outboard provides a 'keel' for the back of the boat and keeps it tracking straight. Without the outboard in the water the stern of the boat with 'wander' uncontrollably from side to side.

Tiller / Foot / Wireless Remote Control

Entry level electric motors will primarily be tiller steer. They are far cheaper as no additional electronics and motors are required for steering. These motors have throttle and steering control on a handle, or tiller, attached to the head of the motor. This means all steering is done manually. There is nothing wrong with this at all. In fact, manual steering is a lot faster than the motor driven steering of remote controlled units! You can alter direction and apply thrust almost instantly. And while tiller model electrics are primarily designed for transom mounting, with the right bracket rigged up they can easily be mounted to the bow.

Foot control electric motors have the steering and thrust controls mounted to a large controller board that sits on the floor of the boat. These are connected to the head unit via a long cable. The cable is usually long enough to allow the pedal to be positioned anywhere in the boat. Generally there is a left and right button, thrust on and off and speed control. Sometimes there might be a thrust lock button as well. The big advantage of foot controlled electric motors is that your hands are free to cast and land fish. Many people prefer these for this reason. Some people go to a little extra effort and mount the foot controller into the floor of the casting deck so the buttons are flush with the floor. But then they can't be moved at all. I really liked using the foot control myself, however, holding one leg up on the controller all day can get very uncomfortable and tiring. The other advantage of the foot controller is that there are no batteries to run flat. Foot controllers do have the tendency to fail due to saltwater corrosion entering through the buttons. So good maintenance is needed.

Wireless remote controls have taken over in recent times. Over the last few years there has been big advancements in these remotes, and the latest Minn Kota remotes have a large clear LCD screen and buttons to perform all sorts of advanced functions. The most basic of the remotes will have the same control as the food pedal; left, right, thrust on/off and speed. Most remotes these days hang on a lanyard around the neck. But there have been watch style remotes in the past. The advantage is the ability to move anywhere in the boat without dragging around a cable. You can fight a fish 360 degrees around a boat and have control the whole time. The Minn Kota electrics also allow you to very easily attach a 2nd or 3rd remote to the one motor, giving your fishing companions the same control. The remotes also work from quite a distance off the boat too! The big disadvantage of this type of controller is having to take you hands off the rod to operate the buttons. But it doesn't take long to get use to this. The other disadvantage is the loss of control if batteries run flat. So always carry either a spare remote, spare batteries or a foot controller, just in case!

Thrust

While outboard motors are rated in Horsepower (h.p.), electric motors are rated in pounds of thrust (lbs). The higher the thrust the more powerful the motor. The main consideration is the ability to push around the weight of the boat given the addition of wind and tide. Generally speaking, the most popular motors are either 55 or 80lbs. There are bigger and smaller, but these two cover over 90% of the boat that would be using one. I have now had a fair bit of experience with both of these thrusts in various sized boats. And I would comfortably say that the 55lbs is suitable for boats around 3.5 to 4.5m, and the 80lbs is best suited to 5.5 to 6.5m. Boats in-between this size range are faced with a difficult decision. On one hand the 55lbs will do the job, but on the other hand the 80lbs will do it far better! And the decision is not a simple matter of the cost difference between the two motors! I'll talk more about this decision after discussing batteries and charging.

There are smaller motors for kayaks and small car toppers and larger 120lb motors for bigger offshore boats.

Batteries

The smaller 55lb electric motors run on a simple 12v battery system. This will be the same voltage used to start an outboard motor and run the general onboard accessories. And while you can run the electric motor off your start battery, it isn't recommended. Electric motors draw a lot of power. Running off a start battery introduces the very real risk of flattening the battery while on the water. It also isn't good running an electric motor off a 'cranking' battery that is used primarily as a start battery. These are not designed to be constantly discharged and recharged. The best battery to run an electric off is a Deep Cycle AGM. And as it happens, these are very expensive! A 100 or 120ah  AGM will give a full days fishing on one charge, probably with plenty left over. I recommend mounting the battery somewhere safe under a hatch in the bow of the boat, and keeping the circuit completely separate from the rest of the electronics. There are ways to wire the battery into the charging system of the motor, but it will add to the cost and complexity of installation. This might be best left to the professionals.

80lb electric motors use a 24v battery system. This is required to provide the extra power. To achieve 24v of power, two 12v batteries are connected in a series circuit. Again, Deep Cycle AGM batteries are the best. As 24v is completely incompatible with other onboard electronics, the circuit should be kept completely separate. But again, there are onboard charging systems available that connect these batteries to the charging system of the motor. I personally have 2 x 120ah AGM Century batteries in my boat and I rarely use more than 1/4 of the capacity in a mornings session.

The 120lb thrust electric motor is a 36v system, achieved with 3 batteries wired in series!

Charging

The simplest method of charging a Deep Cycle AGM battery is with a good quality 240v charger you plug into the wall at home. Ctec are well known as the best quality chargers around. These are designed to charge the batteries in stages, and if left connected to the battery permanently while the boat is out of the water and at home, they will actually prolong the overall life of the battery. 12v batteries require a 12v charger and 24v system will require a 24v charger. Various amperage chargers are available. The higher the output, the more expensive the charger. But the faster the batteries will be recharged.

What I have always done in the past use use an anderson plug to connect the electric motor to the batteries. This is on the bow of the boat and easily accessible. I also have an anderson plug on the end of my charger. So when I return home I simply unplug the electric, and plug in the charger. It remains plugged in until I go fishing again.

The 55 or 80lb decision!

As I said earlier, the decision on electric motor size for boats in the 4.5 - 5.5m range is a difficult one to make. There is far more to consider than just the cost difference between the two motors. I faced this exact issue recently when I purchased my Haines Signature 485sf. It came with a 55lb iPilot bow-mount electric that ran off the 12v dual battery system. These were the same batteries used to start the main motor and run the accessories. But after testing the 55lb on the water I decided to make the costly move 80lb. There were several personal reasons for this besides a pure lack of performance from the 55. Lets face it, the 55 worked! But I was coming from a 3.85m tinnie with 55lb fitted, and was looking for similar performance. This was never going to happen! While the 55lb navigated the boat around the creek tossing lures ok, it was always using high power, running at 70-80% all the time. Strong current and wind created issues and offshore holding on marks in strong current wasn’t going to work too well. The motor would have been on almost 100% power just holding position. In the long term this wasn't going to be good for the motor, or the batteries. Plus I wanted this particular boat decked out properly right from the get go!

But moving up to 80lb presents more problems and costs than just the initial difference in purchase price. And while this difference alone is quite considerable, other associated costs can soon blow the budget completely! The first thing to consider is that this motor is 24v compared to the 12v of the 55. This meant for me the purchase of two 120ah Deep Cycle batteries. These are $500+ each! And now with 24v batteries there is the need for a 24v charger. I opted for a Ctek that was also about $500. I then had to find space under the front hatch to secure two batteries additional batteries. They are heavy and take up a lot of space! So all of a sudden the cost of an 80lb system is substantially more than the simpler 55lb. For me, I think it was worth every dollar!

Minn Kota definitely produce the best quality and most advanced electric motors. Please consider purchasing your next Minn Kota electric motor and accessories locally from Townsville Marine.

In the near future I will be producing a short video review of my 80lb Minn Kota, so keep an eye out for that one in coming weeks.