1994 Johnson/Evinrude Outboards 40 thru 55 Service Manual, Page 160Get this manual

1994 Johnson/Evinrude Outboards 40 thru 55 Service Manual, Page 160

If any cylinder is outside these tolerances, it must be bored oversizeA 0.030 in (0,762 mm) oversize piston is available
diameter If the grooves on the sides of the piston are worn smooth in an area similar to that shown, replace the pistonrJl
11Place 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 gap (0,17-0,43 mm)must be within 0.007-0.017 in 1sl 12Use feeler gauge to check groove side clearance
on the lower square ringsInstall each square ring on its pistonWith the ring fully seated in its groove, make several checks
around the piston The side clearance (0,10 mm)must not exceed 0.004 in 19l 13Use machinist's straightedge to check clearance
on the upper Pressure-BackTM ringsInstall each Pressure-Back 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 groove If the straightedge