Minn Kota trolling motor repairs anyone can do - most anyone..
I couldn't see sending my Endura 55# thrust out for repair for half the $225 I paid for i, so I looked at the parts schematic, opened the unit, got Minn Kota tech support on the line and fixed it myself! One thing about not being mechanically inclined is not giving up and the folks at Minn Kota are VERRRY patient!
One thing that can happen is a burned out switch that will burn out for a few reasons: line wrapped inside the prop causing heat to build and the switch to get a short. The other is water in the lower unit housing from bad seals. Here is what the switch looks like:
http://i76.photobucket.com/albums/j3...ps86902552.jpg
Here is were it's located:
http://i76.photobucket.com/albums/j3...psca24657d.jpg
Easy to change and easy to test! First, remove all wires from the switch. Do not use the battery wires to connect to the battery. Without the switch connected, what's the point? Second, take the other black wire and jump it to the negative post of the battery and then test each colored speed wire (white, red, yellow) by jumping them individually to the positive post. The motor should run, but if not, the problem is down below.
Tolling motors more than 10 years old have seals that can wear out from decay. Water that gets into the lower housing corrodes motor parts such as the armature and brushes as well as causing metal filings between the magnet housing and the armature. All is not lost.
First, you must order a gasket kit from Minn Kota (screw O rings, a large O ring and a white gasket). The shipping is $10 no matter what you order, so be sure there's nothing else that's needed like a switch, screw, extra shear pins, etc.
After taking off the prop and unscrewing the cap screws, here is what the armature looks like with the housing/magnet removed:
http://i76.photobucket.com/albums/j3...ps29e1e9fa.jpg
The round copper plates inside the cone seen above are not shown, but they need to be sanded in one direction across the plates. The copper plates fit between the brushes (seen closed) with springs in the picture:
http://i76.photobucket.com/albums/j3...ps386b4808.jpg
You are looking down into the forward cone of the motor. Beyond that is the coil which rarely has a problem and can only be gotten to by unscrewing the cone from the tm shaft.
I clamp the motor to a saw horse to disassemble and reassemble the motor. Far easier than any other way:
http://i76.photobucket.com/albums/j3...psa6f9e83c.jpg
Just be sure to clean any metal filings from inside the magnets which are located inside the heavy metal cylindrical - lower unit housing and sand the green areas of the armature with low grit sand paper.
note: the metal cylinder has a timing mark on the outside - a deep scratch-like groove in the metal. This must face the fin and be on the same side, otherwise the polarity is reversed and the battery wires have to be reversed. That and the motor doesn't run smoothly.
I'm waiting for a new switch now that the new seals are in place. I tested each wire and the motor whirs quietly at every speed like it was brand new!
Caution: According to tech support, don't run the tm at the highest speed except in an emergency. It is twice the speed and amp draw of the 4th forward setting and puts stress on the unit; same for reverse's highest speed (3rd setting).
It's not rocket science and two basic tools are all you need, plus some help from any one of the 13 technicians at Minn Kota. Lose your schematics or parts list? Give them the serial number and they will email it too you.
(Wonder if Motor Guide has the same deal?)
Frank
