What was found
DURING CRUISE, RIGHT HYDRAULIC QUANTITIY STATUS MESSAGE DISPLAYED. QUANTITY DROPPED TO ZERO, RIGHT PRIMARY HYDRAULIC PUMP WARNING ILLUMINATED. EMERGENCY DECLARED. LANDING UNEVENTFUL. AIRCRAFT GROUNDED. MAINTENANCE FOUND LEAK AT RIGHT PUMP FILTER MODULE. REMOVED AND REPLACED MODULE IAW AMM 29-11-17. DURING TAXI OUT FOR NEXT FLIGHT EVENT REPEATED. MAINTENANCE FOUND RIGHT HYDRAULIC PUMP LEAKING. REMOVED AND REPLACED PUMP IAW AMM 29-11-05.