As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LHR CREW REPORTED RT FUEL QTY DECREASING IN CTR TANK. EMERGENCY DECLARED FLIGHT RETURNED LHR LANDED WITHOUT INCIDENT. ACCOMPLISHED FIM 28-22-00-815-829 WITH NO EXTERNAL LEAKS NOTED. FLIGHT CONTINUED TO DESTINATION. REPLACED RT OVERRIDE PUMP & SHUT OFF SLEEVE AT MIA ON 03/15/2014. SYS GND CHECKED NORMAL, OPERATION CLOSED.