2005 SO Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 254Get this manual

2005 SO Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 254

SAFETY Running outboard too fast (Overspeeding)
'Too fast" means running faster than outboard normally runs on boatRunning too fast can happen when: 1) Using flushing device Turn on water before starting outboard Keep engine speed below 2000 RPMWith no load, outboard will run too fast very easilyWear eye protectors
2) Running with the wrong test wheeL

This may happen if outboard runs too fast
Use the right test wheel
Running outboards: Exhaust fumes