2001-2014 Honda BF/BFP8D, BF/BFP9.9D Outboards Shop Manual, Page 57Get this manual
4) Remove the spark plug caps, then remove the spark plugs using spark plug wrench 5) Visually inspect the spark plug Discard the plug if the insulator is cracked or chipped 6) Remove carbon or other deposits with stiff wire brush 7) Measure the plug gap with wire-type feeler gauge If necessary, adjust the gap by bending the side electrode Standard spark plug Spark plug gap CR5EH-9 (NGK) U16FER9 (DENSO) 0.80.9 mm (0 .0310.036 in) 0.8-0.9 mm 8) Make sure the sealing washers are in good condition Replace the spark plug, if the sealing washer is damaged9) Install the plug fingertight to seat the washer, then tighten with plug wrench to compress the sealing washerIf reinstalling the used spark plug, tighten 181 turn after the spark plug seats If installing new spark plug, tighten 12 turn after the spark plug seats (0 .0310.036 in) SIDE ELECTRODE