On Sun, 23 Sep 2007 12:28:54 -0700, Tim wrote:
Tom, if 8 g. is too big, then go 10g. it's good for about 70a. on
12v . After all, the least it will do while cranking the 25 horse (if
having a hard to start spell). is slowly melt the insulation
off.. ?:
West Marine has some nice charts for sizing wire he
http://www.westmarine.com/webapp/wcs...MarineWire.htm
Unfortunately the web site leaves off the color code for wire size but
it is on page 458 of the 2007 catalog. The smallest size (16 ga,
medium blue) is at the bottom, followed upwards by 14 guage (red), 12
guage (yellow), etc.
Since a 10% voltage drop is acceptable for a momentary load, let's use
the second chart and assume a 40 amp draw for the starter motor.
Following the 40 amp line to the right until we get to a round trip
length of 32 to 40 feet, shows that either 8 ga or 10 ga would be
acceptable. I'd probably make the conservative choice and select 8
guage.