1996 Johnson/Evinrude Outboards 8 thru 15 Four-Stroke Service Manual, Page 135Get this manual
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8Inspect valves for contamination, excessive wear, or damagePay particular attention to the valve seat face, replace if pittedValve stems that show excessive wear or are warped should be replaced9Use micrometer to measure the camshaft lobesRefer to Engine Specifications, Section 1, for dimensions
[] 10Inspect rocker arms for contamination, excessive wear, or damage[] Important Some wear to the face of the rocker arm is normalReplace if wear is severe enough to show porosity (pitting) on the face
11Use micrometer to measure the diameter of each crankpin and main bearing journalRefer to Engine Specifications, Section 1, for dimensions
12Use telescoping gauge or inside reading micrometer to inspect each cylinder bore for an out-of-round, oversize, or tapered conditionBe sure the gauge or micrometer is perfectly square in the bore when measuring13Measure each cylinder in at least two areasMeasure each area twiceThe difference between the two measurements in each area is the cylinder out-of-round dimensionThe cylinder must not be out of round by more than 0.003 in(0,08 mm)