As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
YVR - MAJOR REPAIR - DURING C-03 CHECK A 1 INCH CRACK WAS FOUND ON FLOORBEAM UPPER TEE CAP AT FWD SIDE OF BS 520, RBL 25. MAINTENANCE REMOVED DAMAGED FLOORBEAM UPPER TEE CAP. FABRICATED A NEW REPLACEMENT FLOORBEAM UPPER TEE CAP AND INSTALLED REPAIR PART IAW B737-300 SRM 53-00-51.