2006 SD Johnson 4 Stroke 9.9-15HP Outboards Service Manual, Page 44Get this manual
INSTALLATION AND PREDELIVERY PROPELLER SELECTION
PROPELLER SELECTION
Refer to Propeller Hardware Installation on p44 before installing propellerThe correct propeller, under normal load conditions, will allow the engine to run near the midpoint of the RPM operating range at full throttleRefer to TECHNICAL DATA on p16
Procedure
The propeller selection process is very important to the engine's service life and to boat performanceProceed carefully and thoroughly while considering the following points: During the engine break-in periodrun the outboard at wide-open throttle for only brief periods of time to check full-throttle RPM Use an accurate tachometer to determine the engine's full-throttle RPM while testing various propellers Select propeller that suits the customer's application and allows the engine to run near the midpoint of the full-throttle operating range when the boat has normal load in itRefer to TECHNICAL DATA on p16 To compensate for changes in boat loadingthe engine's full-throttle RPM must be verified periodically