What was found
PIT - FLT 1158 - EN ROUTE FROM PBI TO PIT, AT FL370, CREW REPORTED THE SYSTEM B ELECTRIC HYDRAULIC PUMP LOW PRESSURE LIGHT ILLUMINATED. THEN, ON FINAL INTO PIT, SYSTEM B HYDRAULICS FAILED WITH FLAPS SET AT FIVE DEGREES. FLIGHT LANDED AND TAXIED TO THE GATE WITHOUT FURTHER INCIDENT. AN EMERGENCY WAS DECLARED. MX REMOVED AND REPLACED A LEAKING B SYSTEM HYDRAULIC PRESSURE LINE AT MANIFOLD. REMOVED AND REPLACED NR 2 ENGINE DRIVEN HYDRAULIC PUMP (P/N 65075-06) PER MM 29-15-12 DUE TO FILTER CONTAMINATION. REMOVED AND REPLACED B SYSTEM ELECTRIC HYDRAULIC PUMP (P/N MPEV3-056-9A) AS PRECAUTIONARY. REMOVED AND REPLACED B SYSTEM RETURN AND CASE DRAIN FILTERS, FLUSHED SYSTEM AND REPLACED FILTERS AGAIN. SERVICED SYS