Minn Kota 3HP Repair-Wanna see it's guts?UPDATE 3/19/09

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ben2go

ben2go

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Holy cow!!!!!!I got lucky!!!!!!It took me 2 months to get the prop and drive pin out.Soak in penatrating oil wiggle the prop,repeat daily.Finally after 6 weeks the prop popped off.Soaked the drive pin in penatrating oil and let set over night.Soaked the next day and tried a BIG pair of channel lock pliers.Couldn't pull it out and couldn't push it out.I also tried a C clamp.That pin ain't coming out.Went back to the soak daily idea.After a week I tried a hammer.It moved but hung up.Soaked it everyday for a week.Grabbed a LARGE pair of vise grips and started pulling.I managed to bend the pin over and use leverage to almost get it out.It broke!So I grabbed a 3 inch finish nail and a claw hammer.I knocked the rest of the pin out.I cleaned everything up.Everything looked good except the brushes and the prop end of the motor.I dunno why but the brushes were all chipped up.I used a file and gently filed the rust of the prop end of the motor shaft,and cleaned it up with some 320 grit wet/dry sand paper.It's not purfect,but the little bit of pitting left behind will help hold some antisieze lube.I plan to go with an aluminum prop upgrade from https://www.youngprops.com .It's an upgrade that is only a few dollars more than a direct replacement.So far the only parts I need are brushes and a prop,so about $35.Remember the TM was a freebee.I won't buy the parts until I check the circuit board and controls.If the circuit board is bad,I'll part it out.A new circuit board is $135.More than I will spend on a used 12V TM.Anyway on with the pics.

Control box
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Extreme close up
0820081709a.jpg


Bad side
0820081707.jpg


Good side
0820081708a.jpg


Transom mount
0820081708.jpg


The power end
0820081709.jpg


Extreme close up
0820081708b.jpg


Is it obvious that this unit was submerged in water for nearly a year?Stay tuned part two right after these mesages from our sponsors.Please support our sponsors so we can continue having this great open and FREE forum.
 
This is after the clean up was complete.

Exploded view of the unit apart
1020081717.jpg


This is the motor armature.The paint is scratched up but why?The bearings are good and the armature has good clearance between the magnets.The magnets are smooth with no groves.Windings look great.
1020081718.jpg


Here is the motor case and magnets.The wires are sealed with a white silicone grommet.Take this little piece of advice.Don't remove the wiring from the shaft.Gently$ pull it out a couple inches to check the wiring for bare places.
1020081719.jpg


This is the control box guts. :twisted: I had to partially disassemble it to remove it from the shaft.
1020081718a.jpg
 
Waterwings said:
So that's what it looks like inside ! I wouldn't have the patience you've had with it. I would have brought out the BFH!


sledge.gif



Glad you got it apart to do repairs! 8)
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I don't have patience but I have leaned restraint.I work until I feel like I'm getting angry or stressed.Then I just clean up and shut and lock the building for the night.Unless I'm called in for dinner,then I clean up.By the time I get done cleaning my plate a few times,it's to dark to work. \:D/
 
I don't have patience but I have learned restraint...
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I'm working on that, lol. Seriously though, I have to make myself walk away from the frustrating projects.........but I have been known to throw boards across the yard...but only once, then I take a break :lol:
 
Waterwings said:
I don't have patience but I have learned restraint...
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I'm working on that, lol. Seriously though, I have to make myself walk away from the frustrating projects.........but I have been known to throw boards across the yard...but only once, then I take a break :lol:
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I've been know to toss a few things myself. :LOL2:
 
First I wanna say Thanks to Bob Ridgway of Ridgway Marine.He is helping me solve a problem I ran into with my trolling motor.So far I have not invested any money in it.The reason the TM wouldn't run is, the armature was running under the brushes and brush holders.I got luck and caught it before it ran through the windings.I tried to shim the armature back but then the prop wouldn't fit.There has gotta be an easy solution.This motor is simple as they come.On with the pics.

Banged up brushes.
damagedbrushes.jpg


Banged up armature and windings.
damagedwindings.jpg


The brass square brush holders should ride directly over the round shiny copper part.
brushesoverrun.jpg


Here is everything assembled as it would be in the TM's lower case.Everything is even more out of alignment.
propsetup.jpg
 
dedawg1149 said:
is it usable
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Yes,as soon as I figure out why the brushes are riding on top of the winding connections and fix it.That's why I contacted Mr Ridgway.He is more familiar with TM's than me.Most of my electric motor experience is with autos,industrial machinery, and the occasional home appliance.
 
I should have been a little more forth coming with info.The motor was working until it was submerged for nearly a year.It was left in a boat at a summer camp for preteens.Some irresponsible individual forgot to put away the boat and unit.Come the next summer,the boat was found docked and submerged in 3 to 4 feet of water.The TM was given to me and got it to run.It made a few turns and locked up.Well it stopped turning and was hard to turn by hand.I figured it needed cleaning and greased, or the circuit board had went out.I still need to check the circuit board.I discovered the brush/armature problem during reassembly.The motor was hard to turn and the prop was rubbing the front case.I may need to replace the armature, but I have run them in a lot worse shape.
 
Mr.Ridgway gave me the bad news this morning.Looks like the TM prop took a hard hit and the armature slid forward on the shaft.Mr.Ridgway is looking for me another armature.
 
Good luck with your project, sounds like your getting sound advice and expert on hands help, these 3 hp motors are powerful. I have one and sent it out for repairs (years ago), it made the journey to warrenty shop but when it was time to return it UPS was on strike and I had to wait like a couple of months to get it back.
 
Is it really a 3hp?
I thought that was just a misinterpretation.
Holy Moly, a 3hp would be pretty powerful for an older electric.
 
Zum said:
Is it really a 3hp?
I thought that was just a misinterpretation.
Holy Moly, a 3hp would be pretty powerful for an older electric.
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No it's not really 3 horse power.They put out about 55 to 60 pounds of thrust.On my 10 footer,it will feel like a lot.My boat is only 50 pounds,just under 300 pounds loaded with my outboard.
 
Bad news.Doesn't seem that anyone has an armature that will fit my TM.So I am going to keep looking for an armature or another 3HP.I'll keep mine for parts if I find a good 3HP.
 

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