A D8-200 ON CLBOUT NOSE GEAR DOORS FAILED TO CLOSE. #2 ENG HYD CAUTION LIGHT AND #2 SYS PRESSURE DROPPING TO ZERO. CAUSED BY POOR MAINT PROCS.

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ACR X WAS SCHEDULED AT THE MAINT FACILITY FOR R&R OF THE L-HAND AND R-HAND HYD RESERVOIR OVER-TEMP SWITCHES THE NIGHT OF NOV/SAT/06; BY PRODUCTION CTL. THIS PARTICULAR TASK HAD NOT BEEN DONE BEFORE AT THIS LOCATION OR BY THIS MECH. WE INITIALLY DID NOT HAVE THE SWITCHES IN STOCK. THE ACFT WITH SWITCHES ARRIVED AT XA00. REVIEW OF THE TASK CARD SHOWED A MANUAL REF OF ONLY CHAPTER 29; NO OTHER DETAIL WAS GIVEN. THE MECH WORKING WITH ME LOOKED IN THE CHAPTER INDEX AND DID NOT SEE SPECIFIC INSTRUCTIONS FOR R&R OF THIS SWITCH. THIS HAPPENED BECAUSE IT HAD BEEN ADDED ON A TEMPORARY REVISION TO THE MANUAL THAT IS NOT PLACED IN THE NORMAL INDEX. IT WAS DECIDED TO PROCEED USING NORMAL STANDARD PRACTICES. INITIAL INSPECTION SHOWED ACCESS TO BE LIMITED; AND A 1 1/8 INCH DEEP WELL SOCKET WAS THOUGHT TO BE REQUIRED. A BOX END WRENCH WAS FOUND THAT WOULD WORK WITH DIFFICULTY. THE L-HAND SIDE WAS REMOVED AND REPLACED FIRST; AND A SIGNIFICANT AMOUNT OF FLUID WAS LOST WHEN THE SWITCH WAS REMOVED FROM THE RESERVOIR. THE R-HAND SIDE WAS THEN REMOVED AND REPLACED; AND A GREATER QUANTITY OF FLUID SPILLED. I WOULD ESTIMATE THIS TO BE 1 1/2 QUARTS. THE QUANTITY INDICATORS WERE STILL WITHIN THE SAFE TO OPERATE RANGE; AND A GND RUN TO LEAK CHK WAS PERFORMED. NO INDICATIONS OF HYD MALFUNCTION OR AIR IN THE SYS WERE NOTED. AFTER SHUTDOWN; FLUID WAS ADDED TO THE #1 SYS. THE #2 SYS HAD BEEN FULL ENOUGH TO NOT REQUIRE ANY ADDITIONAL FLUID. ON TKOF; THE NOSE GEAR FORWARD DOORS FAILED TO CLOSE; FOLLOWED BY A #2 ENG HYD CAUTION LIGHT WITH #2 PRESSURE DROPPING TO ZERO. THE CREW RE-EXTENDED THE GEAR USING ALTERNATE GEAR EXTENSION PROCS. DURING THIS TIME; #2 PRESSURE RETURNED/CAUTION LIGHT EXTINGUISHED; FOLLOWED BY A NORMAL LNDG. NO EMER WAS DECLARED. AFTER CLOSING THE BYPASS DOOR/LEVERS; THE NOSE GEAR DOORS WERE CLOSED BY HAND SPINNING THE #2 PROP. AIR IN THE #2 SYS WAS SUSPECTED. ON RE-EXAM OF THE MANUALS; THE TEMPORARY REVISION SPECIFIC TO R&R OF THE SWITCH WAS FOUND; WHICH SPECIFIED BLEEDING OF THE SYS AFTER REMOVAL. 2 METHODS OF BLEEDING ARE GIVEN IN CHAPTER 12; HAND PUMP OR HYD MULE. MAINT IS NOT EQUIPPED WITH A MULE; SO THE HAND PUMP METHOD WAS THEN USED TO BLEED #1 AND #2 SYS. GEAR DOOR OP THEN CHKED SATISFACTORY DURING A GND RUN USING AN OVERRIDE SWITCH. SUBSEQUENT REPAIR OF THE ACFT ENTAILED R&R OF THE #2 HYD PUMP; (RAN UNDER CAVITATED CONDITION); CASE DRAIN FILTER; RE-BLEED OF THE #1 AND #2 SYS USING HAND PUMP METHOD AND BLEED OF THE #2 RUDDER HYD ACTUATOR TO REMOVE TRAPPED AIR CAUSING A PRESSURE DROP ON ENG START. NOTE THAT DURING THIS TIME SEVERAL BLEEDING CYCLES USING THE HAND PUMP METHOD WERE REQUIRED TO REMOVE THE AIR. FACTORS WERE: 1) NEW TASK. 2) HARD TO FIND MANUAL REF. 3) FAILED TO INITIALLY BLEED SYS AFTER SWITCH REPLACEMENT. 4) TOOLING; IT IS THIS MECH'S OPINION THAT THE HAND PUMP METHOD SHOULD NOT BE USED WHEN A GREAT QUANTITY OF FLUID IS LOST; AND MAY NOT HAVE TOTALLY REMOVED THE AIR IN THE SYS IN THIS CASE EVEN IF DONE PREVIOUS TO THE FLT. CORRECTIONS: 1) TEMPORARY REVISIONS IN MAIN INDEX IN MANUALS. 2) HYD MULE REQUIRED FOR SYS BLEEDING AFTER MAJOR MAINT. 3) RESEARCH BY PRODUCTION CTL OF TOOLING; TEST EQUIP; PARTS ETC; REQUIRED BEFORE TASK IS SCHEDULED. 4) TASK CARD CONTAINING COMPLETE MANUAL REF. A SIDE NOTE WOULD BE THAT TOO MANY TASKS THAT WERE ORIGINALLY SCHEDULED FOR COMPLIANCE AT C-CHK INSPECTIONS ARE BEING PUSHED TO OUTSTATIONS WHERE SUPPORT IS NOT ADEQUATE AND OVERNIGHT RON TIME MAY BE INSUFFICIENT.