Mercury Mariner 25HP 4-Stroke Outboard Service Manual 1997, Page 31Get this manual
Propeller Selection For indepth information on marine propellers and boat performancewritten by marine engineerssee your Authorized Dealer for the illustrated "What You Should Know About Quicksilver Propellers and
3After initial propeller installation, the following common conditions may require that the propeller be changed to lower pitch: aWarmer weather and great humidity will cause an RPM loss
Performance
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