1974 Johnson 40 HP Outboard Motors Service manual, Page 57Get this manual
For the first to 10 minutes, operate engine at fa idl eCheck operation of water pump and motor temperature frequentl yFor remainder of firs hour, do not operate engine over 3000 rpm (appr ximate) or one -half throttle (appr oximate) NO1 PISTON ON TOP DEAD CENTER
I MPELLER KEYW AY
With easy planing boats, it would be desirable to bring the boat into planing position with full power and then immediately reduce the throttle setting to apprO ximately 3000 rpm (one-ha l! throttle) BE SURE boat maintains plani ng attitude at this throttle settingDuring second hour, bring boat into planing attitude and reduce power to 4000 pm (approximate) or three-quarter throtUe (approximate), while maintaining planing attitude At intervals during the second hourapply full power for periods of one to two minutes, eturning throttle to Original setting (4000 pmthree-quarters throttle) Avoid continuous full throttle operation for extended period during the next few hours After 10 hours of operationmixture for the motor should be pint to gallons of gasoline