As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MIA - FLT 633 - EN ROUTE SJU-DFW, LEFT HYDRAULIC SYSTEM FLUID LOSS. CAPTAIN DECLARED EMERGENCY AND LANDED AT MIA WITHOUT FURTHER INCIDENT. INSPECTED AND FOUND B-NUT LOOSE ON HYDRAULIC RETURN LINE IN DOGHOUSE AREA FOR NR 1 ENGINE. ACCOMPLISHED RETORQUE OF B-NUT AND SERVICED HYDRAULIC SYSTEM. SYSTEM GROUND CHECKED NORMAL OPERATION. (M)