1990 Johnson Evinrude 120 thru 140, 185 thru 225, 300 HP, P/N 507875, Page 195Get this manual
Inspection 1Before any inspection process can begin, all internal components must be clean and free of excess oil 2Make 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 componentsr;;]
3Check for cylinder head warpage using piece of bar stock or machinist's straightedg#e and feeler gauge
Cylinder head warpage must not exceed 0.004 in(0,10 mm) end to endResu rface or replace head if warpage exceeds this dimension
Use 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 dimensions
5Visually inspect crankcase seal rings for worn, grooved, or chipped conditionIf they appear worn, use micrometer to measure their 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