1971 Johnson 60HP outboards Service Manual, Page 50Get this manual
5- 8 REFERENCE PICTURE
DO NOT scratch cylinder head gasket surface of cylinderUse surface plate to surface this areaWith continued operation of the motor, the cylinder walls will take on glaze which reduces the effectiveness of the seal between the piston rings and the cylinder wallsThe result will be reduced compression and decrease in performance of the motorBefore reinstalling the pistons, break the glaze by using fine cylinder hone to refinish cylinder wallsA few up and down motions of the tool should be sufficient to remove cylinder wall glazeSee Figure 5-21Blowout all oil passages and drainsFigure 5-21Deglazing Cylinder Wall GASKET SURF ACES Remove all traces of dried cement, using trichlorethylene or lacquer thinnerCheck all gasket faces for flatnessUnder certain conditions, gasket faces may warp or spring, particularly where thin sections or flanges are employed and are subect to temperature changesTo check for flatness, lay sheet of No120 emery cloth on surface plate or piece of plate glassPlace the part to be surfaced on the emery cloth and move slowly back and forth several times in figure motion, exerting evenly distributed, light pressureSee Figure 5-22Lift part from surface plate to observe resultsIf the surface is actually warped or sprung, high spots making contact