What was found
ON C-CHECK, REMOVE NR 4 FLAP TRACK FOR INSPECTION AND REINSTALL AFTER INSPECTION C/W. REMOVED LT I/B TRAILING EDGE FLAP IAW B-727 MM 27-51-1. REMOVED NR 4 FLAP TRACK IAW B-727 MM 27-51-31. ACCOMPLISHED VISUAL INSPECTION OF THE NR 4 FLAP TRACK IAW S/B 727-57-0178 FIG 1 REV 3 FOUND MOUNT PAD CORRODED. REMOVED .020 FROM PAD A & B ORIGINAL 0.400 TO 0.380 PER S/B 727-57-0178. REMOVED INSTALLED MACHINED 3 BUSHINGS. INSTALLED NR 4 FLAP TRACK IAW B-727 MM 27-51-31 AS PER S/B 727-57-0178. INSTALLED LT I/B TRAILING EDGE FLAP ASSEMBLY PER B-727 MM 27-51-1. OPS CHECK OK PER B-727 MM 27-51-0.