What Should Be Considered When Wiring an Engine Start Wire?

Question:

First of all I wanted to say thank you for all the resources available on line. I have a question I can’t seem to find an answer to and that is how to choose the appropriate gauge wire for the starting circuit? In my boat, it’s about a 15 foot one way run from my 175hp Suzuki outboard to my starting battery. My house is about 23 ft one way away. I can’t find any clear resources whether I size on continuous alternator output or the short high amp draw of the starter? Any help?? Thanks again.  - Andy

Answer:

Good question, you’re correct both the alternator output amperage and the starter amperage should be considered when sizing an engine cable. Most of the time, the engine draw far exceeds the alternator output. Find out the continuous max amperage draw from the starter and make sure you size the engine cable to consider both amperage and voltage drop.