what size wire to use for starting battery to motor

ajp1977

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Happy Easter all..had a question about my wiring setup. I have a 50hp evinrude outboard that I want to get power to from my starting battery...the total circuit would be no more than 14'. Would 10awg wire be big enough? thanks
 

Georgesalmon

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Re: what size wire to use for starting battery to motor

NO! You need a lot larger. I'd say at least #4 minimum. Isn't there already a cable on the motor? If there is, you need that size or even bigger than that for a longer distance. The starter will draw a lot of current when starting.
 

T_Herrod

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Re: what size wire to use for starting battery to motor

10 awg will not be heavy enough and may get hot.
 

ajp1977

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Re: what size wire to use for starting battery to motor

No I bought the motor separate off a guy with no wires. Thanks for the quick response though!
 

T_Herrod

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Re: what size wire to use for starting battery to motor

Is there any way to get the battery closer to the motor? 14 feet is a long way to run a main battery feed.
 

gm280

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Re: what size wire to use for starting battery to motor

Is your 14 foot estimate a round trip guestimation, being 7 foot one way and 7 foot return? If so, I would buy as large wire size as you can find. 4 gauge would work nicely for that length for that OB starter motor draw. But use quality wire ends too. They will need a very good crimp and/or soldered in place too. If you go to most any auto parts store, they sell battery cables in varying lengths and ends. But them premade for the size you need. However, I seriously doubt you will fine any over 5 or 6 feet long. If you need more then that, try on line wire companies or some serious audio sound shops or even go to a welder's supply store and get their grounding cable cut to size and install the ends...
 

Gyrene

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Re: what size wire to use for starting battery to motor

10 awg will not be heavy enough and may get hot.

Agreed.
Go to an AdvanceAuto, etc. - they have an assortment of battery cables
You want as big as you can find - size DOES matter....:)
 

oldjeep

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Re: what size wire to use for starting battery to motor

The mercury kit for a motor that size has 12 ft. 4 gauge leads

88439A50 - looks like around $60-$70 when searching by the part number.
 
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oldjeep

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Re: what size wire to use for starting battery to motor

Agreed.
Go to an AdvanceAuto, etc. - they have an assortment of battery cables
You want as big as you can find - size DOES matter....:)

Problem with the stuff at an auto parts store is that you will almost never find fine strand battery cables and you need something very flexible to run into the motor base and around to the back where the battery connections are.
 

ajp1977

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Re: what size wire to use for starting battery to motor

the total length of the run would be no more than 14', possibly 12' to be more accurate. Is it not possible to use a heavier duty crimp connector and then heat shrink it?
 

H20Rat

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Re: what size wire to use for starting battery to motor

Problem with the stuff at an auto parts store is that you will almost never find fine strand battery cables and you need something very flexible to run into the motor base and around to the back where the battery connections are.

Agreed, not to mention, you won't find any pre-made battery cables long enough, and auto parts stores rarely carry spools of the big cable.

Go to a car audio shop and have them make up a cable with ends for you, in whatever gauge you want. In the car audio world, 4 gauge is only considered a medium duty. Many of the installs I've done have 1/0 guage running to the trunk!
 

ajp1977

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Re: what size wire to use for starting battery to motor

Thanks. I found prefabbed 2 ga. Top post battery cables in 6' and there actually long enough
 
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