Minn Kota Terrova Help

I have an older Minn Kota Terova 55 thrust, 12 volt trolling motor, with I-polit link. Last night my trolling motor didn’t want to run at first. I dropped it into the drink and the prop would not spin. Everything else worked. I set the motor so it would be in the down position with the motor out of the water. The prop would spin a half of a turn and stop. This happened with the foot pedal and remote. After stowing and deploying, unplugging, and spinning the prop by hand it started to work. Still out of the water I started slowly speeding it up. It stopped at ½ speed and would not start again. Each time I stow, unplug, plug back in, deploy it got a little better until it just worked like nothing ever happened. The beginning of last year I rebuilt and replaced the Armature assembly, brushes, seals, bearing, and O-rings. I put a lot of hours on it last year and this year without any issue since the rebuild. This motor has taken more of a beating in the last 2 months since high school bass league has started than its whole life. My son has plowed into so many rocks, stumps, logs, shore… My first thought when this started was there is a relay contact that stops the motor from turning when it is stowed. I was thinking this contact may be getting worn down. I am not seeing such a relay on the parts diagram. Now I am thinking he smashed it so many times a seal might have failed and water got into the motor. It doesn’t seem to be holding any water.

I’d take it apart again and see if there was water in it. It sounds like it might have water and it might be getting a little crusty around the armature and brushes.

Better yet, make your son take it apart and go through the lower unit. Good opportunity for him to learn, especially since it was likely his doing that ended you up in this situation!

Just ran home and took the prop off. There was a bunch of weeds stuck in there. The weeds were still wet so it is hard to tell if water got into the housing without taking it apart.

rjthehunter wrote:

It sounds like it might have water and it might be getting a little crusty around the armature and brushes.

I think you are right. Do you replace the seals everything you crack it open? I was planning on being on the water Friday and will not be able to get parts in time.

Sounds like a failing main control board to me. They don’t go all at once. Seem to be intermittent until finally nuttin.

I went through the same dance a few years ago with a V2.

Bypass the control board to ensure it is the board.

FishBlood&RiverMud wrote:

Bypass the control board to ensure it is the board.

That is some great information FBRM. Looks like the control board is $200 + with no returns. The control board doesn’t have any terminals and everything hooks up with quick connections. They must have changed the board since it doesn’t match the schematic drawing I found. There is not too many wires coming out of it. Black negative for in and out and red + in or out and white is + in or out. To bypass, I am guessing you just hook the black wires together and the red and white together. Should be easy enough to guess what wires are coming into the board and what ones are going out to the motor once I open it up. Any guess what the resistance should be?

So what you’ll be looking to do is to take the two wires running down the shaft to the motor and apply 12 volts directly to them. Motor should run like on fastest setting.

There will be power coming in and leaving the control board. Disconnect the wires coming in and hook them up to the wires coming out. If this works then control board is your issue.

^ Thanks again for all the great information you share on this site FBRM. You have helped me a bunch over the years. I will have to wait for it to stop working again to test the board. My luck, it will work every time I am in the shop and stop when I am on the water.

Yeah your at a point where failure is intermittent so troubleshooting is going to be a little trouble until it just flat quits working. Luckily parts come fast and installation is a breeze.

So I picked up the new main control board and am having the same problem. It work to about half speed and then stopped working. I could not get it to work the rest of the time on the river. Once I got home to the shop it started working again until I hit half speed. Then it stopped working and would not start back up. Frustrating. I guess I will open the motor again and look tonight. Not sure what is going on.

I just got mine back from Fish Lectronics. Mine had a broken magnet and worn brushes. When if failed on me you could tell it did not have quite the power it should have and then it shut off on its own, I hit the power button and it powered back up then did the same thing, but that time blew the breaker. With mine you could spin the prop by hand and feel that something was not right, it was harder to spin and you could feel it catch something during rotation. The had to replace the lower unit they call it. Cost me $700.00. Not sure this helps but figured I would share. They are great to work with even though I know they are on the wrong side of town for you.

I had the same issue a few years ago, turned out bad seals resulted in water getting into the lower unit… Fish Electronics fixed it for me…

I want to get back out this weekend so I will rip it apart and see what I can see tonight. I will contact fish electronics if things go bad again. Thank you for the information.

I’m sure you’ve already done this, but test the battery. Lower voltage will result in higher current. Could be kicking out the auto resetting fuse. And when you stow it and deploy it, would be enough time to reset that fuse. Just a thought.