1995 Johnson Evinrude "EO" 90 CV 85 thru 115 Service Manual, P/N 503150, Page 26Get this manual
Rated Power
Hot Weatherl High Altitude
Weather, Altitude, and Engine Performance
The horsepower ratings of all engines are those that would be obtained under standard conditionsHowever, changes in weather and altitude will affect the performance of any outboardSome factors that will decrease the output of an engine are: Low barometric pressure High temperature High humidity High altitude
r:;'] Performance can decrease noticeably when an engine is run
on hot, humid daySometimes the weather or altitude alone can cause the engine RPM to drop below the recommended operating rangeIn such case, lower pitch propeller can be used to bring RPM back into the operating rangeIn any case, top boat speed will not be as high as on cool, dry day