What was found
CLIMBING THROUGH FL200; EICAS R HYD QTY MSG FOLLOWED BY R HYD SYS PRESS MSG. COMPLETED QRH. AMM 29-18-04-4 FOUND BLOWN O-RING IN RT IN/BO ENG PYLON ON HYD FILTER CASING. REMOVED AND REPLACED THE RT HYD EDP FILTER MODULE ASSY IAW AMM 29-11-17-4-0 UP TO STEP 3 L (2). SYSTEM STILL REQUIRES SERVICING, OPS CHECK AND LEAK CHECK. AMM: 29-11-17-4, AMM: 12-12-01-3, C/W FLUID SERVICING , LEAK & OPS CHECKS. ALL LEAK & OPS CHECKS ARE GOOD.