Don’t mix metals in your twelve volt wiring, such as using a stainless washer on your battery terminal bolts. Use a copper washer to match the copper wiring. If possible, use copper or bronze bolts on the battery terminal. This is really important with your major twelve volt wiring, not so much with the minor wires, although you may lose some power. Check for the extra heat generated, with your infrared thermometer.
Buy an infrared thermometer, if you don’t have one. Any good hardware store has them. They have multiple uses, such as measuring the changes in temperatures in your water and oil in your engine, and your exhaust emperatures. Remember the water temperature in your engine will change, as you go from area to area with sea temperature changes.
