1997 Johnson Evinrude "EU" 90 thru 115 90 CV Service Manual, P/N 507267, Page 143Get this manual
Inspection
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 or 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
4Use micrometer to measure the diameter of each crankpin and main bearing journalThe lower main bearing journal would only be measured if the bearing was removed for another reasonRefer to Engine Specifications, Section 1, for dimensions5Visually inspect crankcase seal rings for worn, grooved, or chipped conditionIf rings appear worn, use micrometer to measure ring thickness Replace any ring that is less than 0.154 in(3,9 mm) thickInstall seal rings in their original positions on crankshaft after inspection