Battery cable

[rodsnguns]

Hello, New here. I have a 1977 Johnson 70 hp and I am trying to determine the AWG size of the existing battery cables. There are no markings on the current cables. Any input would be appreciated.

 

[alldodge]

Measure the diameter of the wire and do not include the insulation jacket

https://www.firgelliauto.com/blogs/news/understanding-wire-gauge-sizes-awg-101

 

[airshot]

Measure the diameter of the wire and do not include the insulation jacket

https://www.firgelliauto.com/blogs/news/understanding-wire-gauge-sizes-awg-101

Interesting read for a guy that is not an electrician. Will be making a copy for my shop wall, thanks ! Just one question, does it make any difference whether a solid wire or multi stranded wire ??

 

[alldodge]

Interesting read for a guy that is not an electrician. Will be making a copy for my shop wall, thanks ! Just one question, does it make any difference whether a solid wire or multi stranded wire ??

Solid wire should only be used where vibration is not an issue. The current carrying capability is higher for solid wire but not that much more

 

[cyclops222]

I only use stranded Copper wire for battery cables.
NOT Copper coated strands of wire.
Many places sell Copper coated wires.
Engines that take lots of cranking time. WILL WILL cause the non Copper wire to heat up. Reducing the full current to to a lower amount.
Stranded Copper wire ONLY in boat.

 

[rodsnguns]

I only use stranded Copper wire for battery cables.
NOT Copper coated strands of wire.
Many places sell Copper coated wires.
Engines that take lots of cranking time. WILL WILL cause the non Copper wire to heat up. Reducing the full current to to a lower amount.
Stranded Copper wire ONLY in boat.

Yes that's all I use as well. I prefer the tinned copper. My existing cables look to be the 48 year old originals and I had a bad spot in the positive cable which upon dissecting it , it is just jacketed copper stranded wire, not tinned , and corroded under the insulation. There are no markings on the cables anywhere and that is why I am trying to determine the AWG size so I can replace them. Until I buy a caliper, I have no way to measure the diameter.

 

[DeepCMark58A]

4 gauge tinned. According to google AI, with a grain of salt.

 

[alldodge]

Use a measuring tape and get a ball park including the jacket. Go to local store and see what comes closest, and can always buy larger

 

[dingbat]

Hard to beat this place for cable quality and price

Quality Copper Battery Cables Made in the USA! - BatteryCablesUSA

www.batterycablesusa.com

 

[airshot]

I have always been told that stranded wire is better, why....I did not know, but always followed that advice. Solid wire was for your home, everything else was stranded wire. Thanks for the charts, making copies for my shop wall.

 

[dingbat]

I have always been told that stranded wire is better, why....I did not know, but always followed that advice.

Primary reason is flexibly.

The conductor of 12 awg Romax is 0.080” in diameter. The conductor of a 4 awg cable is 0.200” diameter.

Imagine wiring a house with 3/16” bar of copper

 

[Scott Danforth]

500MCM cable had a conductor diameter of 0.97", and weighs 2# per foot

 

[Chris1956]

There is a difference between stranded copper battery cable and marine battery cable. On the latter, there are many more, thinner strands of wire and each one is pre tinned. Obviously marine wire is superior, but costs much more.

 

[airshot]

I have n ever I look at a used boat and motor, I have always looked closely at the wiring, any sign of corrosion was cause for a deeper dive. Bought a few with the plan to rewire everyrhing, but usually look for ready to run stuff. My 1992 has original wiring with the exception of a few add on's.. Most of those have been removed or rewired. No electrician here, in any way, but I do work carefully and make lots of tests and checks to be sure there are no shorts builtin. What n we built our house back in 1999, a friend that is an electrician
looked over my basement wiring....looked great, no problems but used twice as much wire as I needed to use.....