Honda BF8, BF9.9 and BF10 Outboard Motors Shop Manual., Page 18Get this manual
CYLINDER COMPRESSION CHECK 1) Shift the gear into the neutral position
COMPRESSION GAUGE (Commercially available
2) Disengage the emergency stop switch clip from the
emergency stop switch
3) Remove the engine cover and both spark plugs4) Install compression gauge in the No1 cylinder plug hole
5) Disconnect the remote control throttle cable from the throttle arm (Remote control type only)6) Manually hold the throttle arm or throttle lever in the full open position7) Electric starter type: Turn the starter motor using the starter switch (Tiller handle type) or ignition switch (Remote control type) until stable compression is obtainedDo not operate the starter motor for more than seconds at one tryIf stable compression is not obtained within seconds, stop the starter motor and wait for 1020 seconds, and repeat the operation againRecoil starter type: Pull the recoil starter several times until stable compression is obtainedCylinder compression