Honda BF8, BF9.9 and BF10 Outboard Motors Shop Manual., Page 22Get this manual
bIGNITION SYSTEM These outboard motors are equipped with an engine overrev limiter which is provided in the ignition control moduleThe overrev limiter is activated when the engine rpm exceeds (BF9.9Df BFP9.9Df BFlOD, BFPIOD, BFIOB, BFPIOB: 6,300 rpmf BFaD, BFP8D, BF8B, BFP8B: 5,800 rpm)When activated the sparks are emitted to the No1 and No2 cylindersThe overrev limiter may be activated under such conditions as light propeller load or propeller ventilation
a Hard Statting
1 1.Measure the spark plug gap 1
Plggap:0.8-0.9mm[0.31-0.35in Standard plug: CR5EH-9 (NGKI, U16FER9 (DENSO)
No spark or weak spark
2.Perform the spark test again using new spark plugsNo spark