Trolling Motor - Kayak Project (Questions)

[Skippy]

Hi All,

 

Looking into modifying a trolling motor to install at the stern of my Wilderness Systems Ride 135 over the winter.  I have realized that it will require some MacGyvering to make everything work the way that I want it to, but for now wanted to focus on modifying the actual trolling motor.

 

Last winter I put together something that allowed me to add a trolling motor to the side of my kayak (just behind and too my left).  It worked well getting between locations, but having it at the side required manual adjustments from one hand on a fairly regular basis and turning or even going dead straight against wind, waves, current required oversteering in many cases – I think based on it being at the side vs. rear.  I would really like to have it at the rear of my kayak and use the foot pedals to steer – more hands free to continue fishing…

 

I have been doing a lot of research on this, but unfortunately am not particularly handy or mechanically inclined (accountant) – feel free to let me know if I am way off track or need to rethink everything…

 

I have a Minn Kota Endura C2 38 lbs thrust that I plan to use for this purpose.

 

I am planning to add a Pulse Width Modutor (PWM) – some additional reading = here:

 

 

Unfortunately, I need something that can be shipped to Canada – so currently looking into:

https://www.ebay.ca/itm/DC-10-55V-100A-Motor-Speed-Controller-PWM-Reversible-Control-Forward-Reverse/264569858292?hash=item3d9997a8f4:g:1x0AAOSwiX1d-MGd

 

From my understanding – with a standard trolling motor – this would be installed between the battery and the trolling motor, leave the trolling motor control to 5 and then the PWM dial would then control the actual speed (100% variable) using the dial.  If reverse is required, the above noted PWM has a switch that would need to be used…

 

What I know so far:

·         I was planning to remove the Minn Kota head, shorten the shaft and extend the wires from the motor to my seat (approx. 5 feet).

·         Minn Kota’s instruction manuals provide a conductor gauge and circuit breaker sizing table.  For 5 feet recommends 10 AWG.  For most installations this would be extending just the positive and negative cables running between the battery and trolling motor.

·         The Endura has 4 wires running down to the motor – these are significantly smaller gauge than the battery wires that run external to the trolling motor itself.

·         Two of the cables are the +ve and -ve for power, while the extra 2, to my knowledge are designed to regulate the speed and convert power into heat as opposed to propulsion – which makes the trolling motor extremely inefficient – hence the use of a maximizer or PWM to improve the power consumption.

 

What I am currently wrestling with:

1.    Will I need 2 control units going forward?  The PWM to allow for 100% variable speed control as well as the Minn Kota head set to setting 5?  Or can I remove the Minn Kota head from the equation, tying the wires from the trolling motor directly into the PWM and use the PWM to control everything?

2.    If the trolling motor head is no longer required and the PWM controls the power flowing from the battery to the motor, can the 2 “extra” wires that regulated speed previously be ignored?

3.    I want to extend the wires from the trolling motor forward so that the PWM would sit either directly in front of me or to my left (position TBD but again ~ 5 feet should work).  Effectively, my thoughts were battery connected to PWM using the existing battery cables that would normally run from the trolling motor to the battery.  Then 5 fees of 10 AWG connecting the PWM directly to the shortened trolling motor via the existing smaller gauge wires.

 

I think that is a good staring point for now.

 

Thanks in advance for any assistance.

Scott

[DanielG]

hi, I'm the original poster you quoted.

 

I did install the unit when I took the boat out in the fall. It does work but I haven't put it back in the water yet to try it out wet as it's winter here in Maine.

 

I've been using trolling motors like this for a long time. If you remove the head you'll see a red and black wire that is larger than the others. This is simply positive and negative directly to the motor. You can cut or cap off the other wires and connect directly to these. I also cut the shaft down and put a 3/4" pvc elbow on them where the wire comes out. I filled the top of the shaft with silicon to make a plug... just in case.

 

You're right, the motor wires aren't that big. They don't have to be. But, for longer lengths you need a good size to help cut down on the resistance. 5 ft isn't that long though.

 

I use it on a converted sailing catamaran I made. The intstructable is here with some info about the motors. It was made pre PWM though. It also has information on my use of a linear actuator for steering.

 

If you have any questions, feel free to ask

[Skippy]

Thanks DanielG,

 

Based on some additional research last night I believe that I have answered my questions and have a plan going forward. 
 

1.  I have seen several examples where the trolling motor control unit was completely removed and everything was controlled directly by the PWM. 
2.  The “extra” two wires controlling speed were not used in those other installations - speed and direction (forward or reverse) was controlled directly by the PWM. 
3.  I will try to extend the wires from the trolling motor with 10 AWG. 
 

A potential issue - the most likely point of failure going forward will be the PWM. Some builds notes that they fried the PWM - if this were to happen on the water and the trolling motor head has been removed, you are effectively left without a trolling motor.  It was noted the key was to ensure the WPM selected can handle the appropriate amps and the trolling motor is smaller thrust as larger thrust motors draw much more amps from the battery.  30 to 40 lbs were recommended and the 100A (max) with 60A continuous PWM was strongly suggested. 
 

I will look into the PVC elbow to cap the trolling motor - thank you for the suggestion. 
 

I will be ordering a couple of PWM soon and everything will be on hold until they arrive. 
 

Thanks

Scott