1996 Johnson/Evinrude Outboards 50 thru 70 3-Cylinder Service Manual, Page 157Get this manual
Cleaning
Before inspecting or assembling powerhead, all internal components must be perfectly clean and free of contaminants1Remove any carbon accumulation from exhaust port areas2Remove any carbon accumulation from cylinder head combustion chambers3If cylinder walls are glazed from extended use, use medium grit cylinder hone to resurface wallsUse slow RPM to achieve strong "crosshatch" pattern for best oil retention and ring sealing
avoid piston or cylinder block damage, restore the chamfer to all port edges using ball hone or other suitable
ill gloves when using
'" To avoid personal injury, wear eye protection and rubber OMC Gel Seal and Gasket Remover