What was found
LEFT MAIN HYDRAULIC PRESSURE WENT TO ZERO PSI ON DESCENT INTO SAN. THE LANDING GEAR WAS MANUALLY PUMPED DOWN AND THE AIRCRAFT LANDED WITHOUT INCIDENT. UPON INVESTIGATION MAINTENANCE FOUND A HOLE IN THE FLEXIBLE HOSE BETWEEN THE LEFT ENGINE HYDRAULIC PUMP AND THE LEFT FIREWALL. THE HOSE WAS REPLACED, THE FILTERS WERE CHECKED, GEAR SWINGS AND LEAK CHECKS WERE PERFORMED. THE AIRCRAFT WAS RELEASED TO SERVICE WITH NO FURTHER PROBLEMS.