What was found
PDIS 304 29-02 6389 08JUL19 PDX FACT U LOGPAGES:2466655 DURING CRUISE FLIGHT, WE GOT A LEVEL ONE ALERT HYD 3 ELEV OFF WITH 4.4 QUANTITY IN HYDRAULIC SYSTEM #3. QUANTITY CONTINUED TO SLOWY DECREASE TO 3.0. DURING APPROACH CONFIQURATION, QUANTIY DROPPED TO 2.4 WITH ASSOCIATED ALERT HYD 3 QTY LO. AFTER LOWERING THE LANDING GEAR WITH FOUR GREEN INDICATIONS, THE QUANTITY RAPIDLY DROPPED AND GOT A LEVEL 2 ALERT HYD 3 FAIL. FACT 08JUL19 06:08 PDX U FOUND HYDRO FLUID LEAK COMING BACK DUAL BRAKE CONTROL VALVE IN RT GEAR WELL. FOUND LINE, BNUT, AT SUPPLY PRESSURE PORT LOOSE. TIGHTEN BNUT AS REQUIRED. REF. MM 32-44-04-2. RESERVICED #3 HYDRO QUANTITY TO 7.5. RAN AUX HYDRO SYSTEM, ALL THREE SYSTEMS FOR 20-30 MINUTES FOR LEAK CHECKS. NO LEAKS NOTED. CHECKED OTHER AREAS OF AIRCRAFT FOR OTHER POSSIBLE LEAKS. NO LEAKS NOTED. QUANTITY REMAINED THE SAME. RAN ALL ENGINES PER JRH FOR 10-15 MINUTES WITH NO LEAK NOTED DURING RUN. AGAIN QUANTITY FOR SYSTEM #3 REMAINED THE SAME. AIRCRAFT OK FOR SERVICE.