i. Check cylinder liner upper counterbore.
(1) Check counterbore and remove any loose scale, dirt, nicks, and burrs.
First measure counterbore depth on ledge at edge of liner bore.
(2) Measure counterbor e depth at four places 90 degrees apart on counterbore ledge with tool no. 3376220
gage block and dial indicator. Mark location of gage block on top of cylinder block.
(3) Record readings for comparison.
(4) Move gage block and gage on ledge at point closest to counterbore wall.
(5) Measure depth at same four 90 degree locations as marked on top of block.
(6) Record readings for comparison.
(7) If difference between any one outer edge reading and its inner reading is greater than 0.0014 in. (0. 0355
mm), counterbore ledge must be resurfaced (para 3-9b). This indicates that ledge is slanted beyond
(8) Compare four inner edge readings. If variation between readings exceeds 0.001 in. (0.025 mm),
counterbore ledge must be resurfaced. This indicates that ledge surface is not perpendicular to