The Minn Kota wiring guide for a 55-lb thrust motor recommends 6 AWG (for a 10' run). My hazy recollection is the heavier gauge wire is called out as it assumes 2 or more conductors in a wire bundle, and bundled wire can get hotter. But if you have unbundled wiring then two 8 AWG individual wires is sufficient.

 

I'm trying to size my wire for an 8' to 10' run in a kayak to power a Motorguide Xi3 55-lb thrust motor. Battery is an Ionic 12v 100aH lithium.

 

I might buy custom cables cut to length with my desired connectors installed if someone can recommend a place that does this.

Doesn't matter if it's bundled or unbundled...if it calls for 6AWG, that's what you should use.

Since you're buying wire I'd go with 6awg.  If you already had 8 gauge ran I'd say try it with a 50 amp breaker.  Has your battery shipped?  I suspect Andy-Drewcraft could make you a couple wires with terminals.  

If I'm going to use Anderson connectors I really don't need anyone to make anything, right? Just get the right length of 6AWG and I can install the Anderson connectors? I assume they just attach with an allen wrench or screwdriver?

 

This one place online is quoting me $66 for a custom 10' 6AWG cable with 2 Anderson plugs. Seems high.

11 minutes ago, wasabi_VA said:

If I'm going to use Anderson connectors I really don't need anyone to make anything, right? Just get the right length of 6AWG and I can install the Anderson connectors? I assume they just attach with an allen wrench or screwdriver?

 

This one place online is quoting me $66 for a custom 10' 6AWG cable with 2 Anderson plugs. Seems high.

The terminals on an Anderson connector need to be crimped or soldered. 

I don't think my crimpers will work with a 6ga crimp. I do have solder slugs so I guess I will do it that way. You just drop a solder slug into the connector and heat with a torch until the solder melts, then insert wire, right? Been awhile since I've actually done that.

I'm always willing to use a project as an excuse to build out the tool collection further.  For limited use tools, I do sometimes go cheap.  In preparation for installing the same motor on my kayak using 6ga tinned marine wire, I picked up a hydraulic crimper from harbor freight for $70. 

A good quality hand crimper is really all you need, I got the Channel Lock after trying a few for 4-8 gauge on the air handler.

A propane torch, flux (preferably the paste type) and solder (not a fan of flux core type) are all you need. I prefer soldered connections over any crimp or mechanical connection.

 

If the connectors are pre filled with solder, just wipe a little flux on the opening where youll shove the wire. Dip the exposed cable wire in the flux and then heat up the connector with the torch until solder turns liquid (youll see it visually). REmove heat and push the fluxed wire into the hole and you are good. 

 

Where I can I prefer to pre-tin the wires but even with a torch I found it hard to heat up the wire fast enough to tin it without burning up the insulation. 

The first step for soldering a wire is to get a good mechanical connection.   Solder alone is prone to problems from vibration as well as heat.   

23 hours ago, Woody B said:

The first step for soldering a wire is to get a good mechanical connection.   Solder alone is prone to problems from vibration as well as heat.   

So...  dip wire end in flux, insert into end, mechanically crimp, then apply heat and solder and the flux will draw the solder in?  I have a few connections to make, curious how to do both solder and mechanical.

 

Thanks

Joe

How long is your kayak?

 

And how long are the leads that came on the trolling motor from the factory? Maybe 3 or 4 feet? The chart gives wire sizes for the lengths you add. They call it wire extension length.  If you are only adding 5 feet the chart says 8 AWG will do. (I'd measure what came on my Maxxum 70 and Endura 55, but I hacked them and modified them years ago.)

 

From the line below MK chart "NOTICE: Wire Extension Length refers to the distance from the batteries to the trolling motor leads."