Wiring Question need Help!

[LadyLuck]

We are trying to size the cranking battery wiring for the 300 HP E-TEC outboard engine model E300dpzscs, with the battery located about 15 feet (30 ft roundtrip) from the engine. Evinrude tech service recommends # 2 wire for 11-15 ft round trip , and # 1 wire for 16-20 ft. round trip. They have no recommendation above 20 ft. Any recommendations, personal experiences, or references you can provide will be appreciated.

LL

[DonV]

Go here and use the tech calculator tab.

http://shop.genuinedealz.com/Store/Tab.aspx?tabid=2

[bridgeman]

May not be the way you want to do it but I went to the auto parts store and purchased the best set of jumper cables and removed the ends, no problems for 3 years

[strick]

Bigger is always better.

strick

[DonV]

Amen!! #2 is $2.31 per foot and #1 is $3.42 at Genuinedealz. For a $1.11/ft difference in price, refer back to Strick's reply.

[htillman]

Also find a welders supply store and buy heavy duty welders cable.

[Caymanboy]

I would go with #1 at the VERY least if not #0, important also is to have a battery with 1000 CCA. The most important factor is to have tinned cable. Remember, you get what you pay for.
OP

[Blue_Heron]

DonV had it right in his first post. Use the calculator.

You need to know how many amps your starter circuit requires and then calculate wire size based on 3% or less voltage drop. If you don't know the starter circuit amperage, you might be able to calculate it backwards by using the lengths and wire sizes the dealer recommended.

If your wire size is too small, your voltage drop will be above the recommended limit. It may work fine for a while, but motors don't like to run on low voltage. Buy the right size wire now, or maybe buy replacement starters later.
Dave

[Mardav]

this may be what you are looking for:

www.engineeringtoolbox.com/amps-wire-gauge-d_730.html
This is what I used in wiring my inverter on the "big boat" and it works fine.

[eggsuckindog]

sure you count both ways??, sounds like one way to me