1998 Johnson Evinrude "EC" 90, 100C, 105C, 115, 150, 150C, 175 60 deg. LV Service Manual, P/N 520210, Page 162Get this manual
6Thoroughly wash entire cylinder block and crankcase with warm, soapy water to remove all traces of contaminants7Air dry cylinder block and crankcaseBlow all holes and passageways with compressed air 1.1 To avoid person injury, wear eye protection and
pressed air pressure at less that 25 PSI (172 kPa)
8Cover the cylinder walls with liberal amount of Johnson or Evinrude Outboard Lubricant to protect them from corrosionInspection 1Before any inspection process can begin, all internal components must be clean and free of excess oil2Make visual inspection of all internal componentsCheck for unusual wear patterns, scuffing or deterioration of aluminum parts, heat-related discoloration of bearings and bearing surfaces, and broken components
3Check for cylinder head warpage using piece of bar stock or machinist's straightedge and feeler gauge set Cylinder head warpage must not exceed 0.004 in(0,10 mm) end to endResurface or replace head if warpage exceeds this dimension