As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LOST ALL HYD B SYS FLUID A SYS DROPPED TO 2.5 GAL AND STAYED. DID RED TABS PROC FOUND CK VALVE COUPLER INSIDE HYD BAY LEAKING. *S/D* REMOVED BOTH B HYD PUMPS PER 727-200 MM 29-12-011-2. REMOVED AND REPLACED HYD DRAIN FILTER ASSY PER MM 29-12-021-2. INSTALL NEW COUPLING HALF''S AND CK VALVE PER MM 29-14-00.