Trolling Motor Wiring/Circuit Breaker/Fuse Questions

jeff_j

Recruit
Joined
Jun 30, 2020
Messages
3
Apologies for breaking protocol with my question from another thread.

I have a 14' Valco aluminum boat with an outboard and a transom mounted trolling motor.

I have a battery mounted near the bow (for weight distribution) and have run 6 gauge wiring to that back of the boat where it is connected to the trolling motor wiring. The battery is in a Minn Kota Power Center battery box that has a 60 amp breaker built into it. I took the trolling motor off of the transom to get it out of the way while I was working on the outboard.

I went to put the trolling motor back onto the transom to go boating and tried to turn it on and it didn't work. I noticed that the handle was about halfway between OFF and 1 (forward). Probably got nudged there when I set onto the floor of the boat.

I opened up the trolling motor to look around and it wasn't pretty. Two of the wires from the controller heading down into the mast had obviously got hot and melted insulation. I removed the prop and got into the lower unit and the armature was black, the brushes were stuck in their mount, and several wires had the insulation burnt completely off of them. There was a black gooey tar like substance present and the small was definitely of something that was burnt.

SO, while the 60 amp circuit breaker absolutely protected the 6 gauge wiring from the battery back to the trolling motor, and the wiring going into the trolling motor (maybe 10 gauge?), it did nothing to protect the wiring in the trolling motor itself (which is smaller that the wiring from the battery and the trolling motor external wiring).

I was able to find an almost exact replacement trolling motor on craigslist for $30. Going forward, I am wondering if I could install an additional fuse to protect the trolling motor wiring somewhere in or near the trolling motor to protect it should I find another way to put it in jeopardy?

What size (30 lb thrust motor that draws 30 amps) fuse?

And where should it be located?
 

jeff_j

Recruit
Joined
Jun 30, 2020
Messages
3

chris.olson

Petty Officer 2nd Class
Joined
Mar 15, 2009
Messages
173
Great! I personally prefer the Maxi Fuse holders and that's what I use inline on the trolling motor on our bass boat. They come with 6 AWG wire leads and will handle up to a 60A fuse. Manual reset breakers are ok for awhile. But they do have moving parts that eventually don't stand up to the marine environment. When we sailed blue water with our 54 foot sailboat for three years in the Caribbean we ended up gutting the factory breaker panel and replacing the breakers with fuses. Put a little dielectric grease on the blades on the fuses so they don't corrode and they stand up to the marine environment very well.
 
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