2004 SR Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 198Get this manual
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 outboardKeep engine speed below 2000 RPM With 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 fastUse the right test wheel
Running outboards: Exhaust fumes