how many amps does the starter draw?

comet424

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hi I deciding to re wire my boat to put the batteries at the front of the boat since they be out of the way instead of battery boxes at the back, but I wanted to know how many amps does the starter use as I was going to use 4 gauge booster cable wire and just cut it up

this is for that 1978 115 hp engine I working on
 

tpenfield

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217 amps, but that is just an estimate. It is a lot, instantaneously, Thicker cables are better. There are some guidelines that you can google to right-size the cables based on load and length.
 

tpenfield

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Edit: may be more in the 150 amp range for your outboard. Was thinking and I/O starter. Still quite a bit though.
 

tpenfield

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oh ok
ya I following this guide
http://www.offroaders.com/tech/12-volt-wire-gauge-amps.htm

just wasn't sure
so roughly 20 feet

but then again its only instant for a few seconds burst really its not a constantly running

If you are undersized on the wiring, it will eventually 'cook' the wire, eventhough it is only a few second burst, and the worst of the current is while the starter motor is spinning up to speed after it engages, which is fractions of a second.

Based on the chart, 4 GA looks OK.
 
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