What was found
98-245 AT FLT LVL 200, ON CLIMB-OUT 'A' SYS QUAN WAS 0.6 GAL GOOD PRESS. ON DESCENT QUANTITY DECREASE TOWARD 0 PRESS ERRATIC. MAN EXTEND GEAR AND FLAP A FLUID SHUTOFF SWITCH CLOSE AT 0835Z. FOUND LEAK LWR RUDDER PWR UNIT AT BASE RUDDER LOAD LIMIT VALVE MT PAD. REMOVED AND REPLACED PAD,VALVE PER MM 27-20-142 PG 401. SERV HYD SYS & OPER ALL SYS TO PURGE OUT AIR. OK FOR SERV.