Well, I did it…. Minn Kona help needed

1. The output from the controller to the motor was giving 26V+, so the iPilot controller seemed good. (Thankfully!)
2. I then ran power directly to the motor leads... nothing. Problem is down in the motor end.
3. I pulled the prop and cap off the motor, and everything looked good. No obvious burned spots on the armature, but I definitely smelled something burned.
4. I pulled the brush assembly, and they looked fine. HMMM...
5. I tested the resistance of the brushes, and both were good at 0.01 ohm resistance.
6. I tested the voltage of the input to the brushes and it was 26V. Not the feed wires.
7. When putting the brushes back in, I noticed that one of them was sticking in a spot. Could it be that easy????

thill said:

Thanks. Yes, we caught a number of redfish (red drum) along with bluefish, flounder, trout and some other species. A great day on the water.
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UPDATE...

I pulled the head off the motor to start testing.

1. The output from the controller to the motor was giving 26V+, so the iPilot controller seemed good. (Thankfully!)
2. I then ran power directly to the motor leads... nothing. Problem is down in the motor end.
3. I pulled the prop and cap off the motor, and everything looked good. No obvious burned spots on the armature, but I definitely smelled something burned.
4. I pulled the brush assembly, and they looked fine. HMMM...
5. I tested the resistance of the brushes, and both were good at 0.01 ohm resistance.
6. I tested the voltage of the input to the brushes and it was 26V. Not the feed wires.
7. When putting the brushes back in, I noticed that one of them was sticking in a spot. Could it be that easy????

I pulled the brushes, and ran a small file through the slides, taking off a little burr or maybe a melted spot. I also touched up the brushes and everywhere that could cause a problem. Now the brushes slid smoothly.

I put everything back together and Viola- She works perfectly again! She just lost contact @ one brush.

I believe the motor WAS getting hot, and that caused a melted spot in the slide that holds the brushes. Fortunately, it lost contact before causing catastrophic damage. I think I got off easily, but learned an important lesson.

From now on, 8.5 is going to be my new top speed except for a minute or two, as needed!

All is well that ends well.

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thill said:

Thanks. Yes, we caught a number of redfish (red drum) along with bluefish, flounder, trout and some other species. A great day on the water.
View attachment 120879
View attachment 120880
View attachment 120881
View attachment 120882
View attachment 120883

UPDATE...

I pulled the head off the motor to start testing.

1. The output from the controller to the motor was giving 26V+, so the iPilot controller seemed good. (Thankfully!)
2. I then ran power directly to the motor leads... nothing. Problem is down in the motor end.
3. I pulled the prop and cap off the motor, and everything looked good. No obvious burned spots on the armature, but I definitely smelled something burned.
4. I pulled the brush assembly, and they looked fine. HMMM...
5. I tested the resistance of the brushes, and both were good at 0.01 ohm resistance.
6. I tested the voltage of the input to the brushes and it was 26V. Not the feed wires.
7. When putting the brushes back in, I noticed that one of them was sticking in a spot. Could it be that easy????

I pulled the brushes, and ran a small file through the slides, taking off a little burr or maybe a melted spot. I also touched up the brushes and everywhere that could cause a problem. Now the brushes slid smoothly.

I put everything back together and Viola- She works perfectly again! She just lost contact @ one brush.

I believe the motor WAS getting hot, and that caused a melted spot in the slide that holds the brushes. Fortunately, it lost contact before causing catastrophic damage. I think I got off easily, but learned an important lesson.

From now on, 8.5 is going to be my new top speed except for a minute or two, as needed!

All is well that ends well.

Click to expand...

GTS225 said:

I'm not too sure, but I think I may see the problem.
In your thread title, you said your motor was a "Minn Kona"... Might you have mistakenly purchased a Chinese knock-off?

Can't help with the technical stuff, otherwise.

Roger

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wmk0002 said:

Glad you figured it out. I hadn't heard about the issues with running on high for extended periods. I wonder if people who run boats on electric only lakes and use a TM as their primary propulsion run into this a lot? I bet they are running on full blast to get from A to B if they dont plan on fishing in between.

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thill said:

HAHAHAHA!!!!! Good one.

I'm innocent! Spell-correct got me.

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Billy H said:

Everything perfect, biggest issue was putting the armature back in. It pulls so hard it slams knocking the brush retainer clips out of whack.

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Billy H said:

I do it weekly. Run my 24 volt 80 pound minnkota terrova on 10 for at least 40 minutes straight, fish around for a few hours then do the same on the way back. Using LiFePo4 batteries. Only had the one problem a couple years ago. Fried red cable inside the head. I pulled the armature this winter to inspect things. Everything perfect, biggest issue was putting the armature back in. It pulls so hard it slams knocking the brush retainer clips out of whack.

Thill glad your back in buisness

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thill said:

That's good to know.

What size/weight is your boat? I'm guessing doing it in a relatively light tin boat is different than doing it in my 22 CC in heavy Chesapeake Bay winds and tides. That motor was getting maxxed out in those conditions, so it was definitely user error on me.

For what it's worth, if you put the armature in FIRST, and then slide the magnet sleeve on, it goes much better. It's a pain doing it the opposite way.

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Still Afloat said:

Check the schematic for the motor. Look for a fusible link or thermal switch. If that checks out Ok test the motor windings. They should not be open, maybe a few ohms 0.5 to 5 ohms but, that’s just a guess.

If you have a gas kicker motor you can use the kicker to almost hold the position or desired speed. Then the TM makes up the difference and does course corrections. Just lock the kicker straight ahead.

Here’s an example TERROVA 80 schematic. Yellow highlight is the fuse. Green highlight are leads to check motor windings.

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Tin Man said:

thill, Sorry to hear about your MK issue. Perhaps that fuse is a thermal switch (yellow highlighted are in schematic) to protect windings and such from overheating. That would be best scenario. Easy enough to test. As others have shared, just follow the process of elimination and you will find, repair, and be ready for the next big one!!

Btw…Nice fish !!!

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Billy H said:

I’ll remember that advise if I ever crack that motor open again. Though I’m not sure that’s an option on this old motor.,,

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