What was found
DURING HEAVY MAINTENANCE: AFTER REAMING OF AFT LUG BORE AT RH ENGINE PYLON INBD SPAR, CRACK WAS FOUND AND SPAR MUST BE REPLACED; REF TOMX WO# 2452 NR# 00431 RH ENGINE PYLON INBD SPAR WAS REPLACED PER SRM 51--43-03, SRM 51-43-04, & EMB ANNEX A RH & LH PYLON - INBOARD & OUTBOARD UPPER SPAR REPLACEMENT PROCEDURE.