1993 Johnson Evinrude "ET" 60 degrees LV Service Manual, P/N 508286, Page 138Get this manual
13 area should be measured twiceThe difference between the two measurements in each area is the cylinder out-of-round dimension The cylinder must not be out-of-round by more than 0.004 in(0,10 mm)
1sl7Measure each cylinder in at least two areas as shownEach
13 taper
1sl 8The dimension difference between the two areas is cylinder The cylinder taper must not exceed 0.002 in(0,05 mm)
1sl 9The difference between your measurements and standard bore dimension is cylinder oversizeRefer to Engine Specifications, Section 1, for dimensions The cylinder must not be oversized by more than 0.004 in(0,10 mm)If any cylinder is outside these tolerances, it must be bored oversizeIt is permissible to have one or more oversize pistons in an engineRefer to Engine Specifications, Section 1isl 10Use micrometer to check piston conditionMake at least two measurements, 90 from each otherMeasure the piston diameter V4 in(6,4 mm) above the bottom edge ofthe piston skirt The difference between the two piston measurements must not exceed 0.003 in(0,08 mm)f'7l 11For the new ring sets, make the following inspectionsPlace each ring, separately, in its respective boreUse piston to square the ring in the cylinderUse feeler gauge to measure the ring end gap The ring end gap must be within 0.011-0.023 in(0,280,58 mm)f81 12Use feeler gauge to check groove side clearance on the lower, square ringsInstall each square ring on its piston With the ring seated in its groove, make several checks around the piston The side clearance must not exceed 0.004 in (0,10 mm)Use machinist's straightedge to check clearance on the upper tapered ringsInstall each tapered ring on its pistonWhen checked with the straightedge, there should be enough ring clearance to allow the straightedge to touch the piston on both sides of the ring grooveMake several checks around the piston