2004 SR Johnson 2 Stroke 9.9, 15, 25, 30 HP Outboards Service Manual, Page 195Get this manual
POWERHEAD INSPECTION
INSPECTION
All Models
Before any inspection process can begin, all internal components must be clean and free of excess oilRefer to CLEANING on p193Make 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 componentsUse micrometer to measure the diameter of each crankpin and main bearing journalMeasure the lower main bearing journal if the bearing was removedRefer to TECHNICAL DATA on p30 for dimensionsCheck 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) per inch ot measurementReplace head it warpage exceeds this dimensionMeasure each cylinder in at least two areas as shownEach area should be measured twiceThe difference between the two measurements in each area is the cylinder out-ot-round dimension The cylinder must not be out-ot-round by more than 0.003 in(0.08 mm)