Narrative:

Aircraft arrived at gate with log write-up, with fault code 36-xx-yy. Fim manual said to change high pressure shut off valve. Lead mechanic called maintenance control and got MEL 36-xx- xy for system. MEL book has picture of location of valve at 1 O'clock position on right side of engine. The maintenance manual states in 36-xx-yy page 401 that valve is located high on right hand side of engine. There are 2 valves on right side of engine, one at 1 O'clock position and one at 3 O'clock position with same part number and are interchangeable. MEL states to lock hpsov (high pressure shut off valve) in closed position, which maintenance manual said is high on right hand side which is the pressure regulator valve. We locked closed valve high on right side of engine and complied with the rest of MEL which includes lockout thrust reverser in forward thrust position and dispatched. Pilot did not turn engine bleeds on till after takeoff at 30000 ft (used APU bleed air till then). He had no bleed pressure on right hand system and returned to field. I believe MEL book and maintenance manual are incorrect and very misleading and need to be updated to show proper valve location on engine. Callback conversation with reporter revealed the following information: the reporter stated the rendering inoperative of the wrong valve using the MEL, maintenance manual and the maintenance manual for valve identify and location has resulted in at least 5 incidents. The reporter said this problem was discovered and reported by several mechanics 9 yrs ago but not corrected. The reporter said the boeing manual states the high pressure shutoff valve is located directly forward of the precooler but this is actually the location of the pressure regulator valve. The reporter stated the mechanics involved in this incident have been given the assignment to correct the procedure with adequate pictures to preclude a repeat of this incident.

Google
 

Original NASA ASRS Text

Title: A B767-200 WAS DISPATCHED WITH THE #2 ENG PNEUMATIC SYS INOP DUE TO THE INCORRECT VALVE RENDERED INOP CAUSED BY MISLEADING AND VAGUE VALVE LOCATIONS IN THE MEL, MAINT MANUAL AND BOEING MAINT MANUAL.

Narrative: ACFT ARRIVED AT GATE WITH LOG WRITE-UP, WITH FAULT CODE 36-XX-YY. FIM MANUAL SAID TO CHANGE HIGH PRESSURE SHUT OFF VALVE. LEAD MECH CALLED MAINT CTL AND GOT MEL 36-XX- XY FOR SYS. MEL BOOK HAS PICTURE OF LOCATION OF VALVE AT 1 O'CLOCK POS ON R SIDE OF ENG. THE MAINT MANUAL STATES IN 36-XX-YY PAGE 401 THAT VALVE IS LOCATED HIGH ON R HAND SIDE OF ENG. THERE ARE 2 VALVES ON R SIDE OF ENG, ONE AT 1 O'CLOCK POS AND ONE AT 3 O'CLOCK POS WITH SAME PART NUMBER AND ARE INTERCHANGEABLE. MEL STATES TO LOCK HPSOV (HIGH PRESSURE SHUT OFF VALVE) IN CLOSED POS, WHICH MAINT MANUAL SAID IS HIGH ON R HAND SIDE WHICH IS THE PRESSURE REGULATOR VALVE. WE LOCKED CLOSED VALVE HIGH ON R SIDE OF ENG AND COMPLIED WITH THE REST OF MEL WHICH INCLUDES LOCKOUT THRUST REVERSER IN FORWARD THRUST POS AND DISPATCHED. PLT DID NOT TURN ENG BLEEDS ON TILL AFTER TKOF AT 30000 FT (USED APU BLEED AIR TILL THEN). HE HAD NO BLEED PRESSURE ON R HAND SYS AND RETURNED TO FIELD. I BELIEVE MEL BOOK AND MAINT MANUAL ARE INCORRECT AND VERY MISLEADING AND NEED TO BE UPDATED TO SHOW PROPER VALVE LOCATION ON ENG. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE RENDERING INOP OF THE WRONG VALVE USING THE MEL, MAINT MANUAL AND THE MAINT MANUAL FOR VALVE IDENT AND LOCATION HAS RESULTED IN AT LEAST 5 INCIDENTS. THE RPTR SAID THIS PROB WAS DISCOVERED AND RPTED BY SEVERAL MECHS 9 YRS AGO BUT NOT CORRECTED. THE RPTR SAID THE BOEING MANUAL STATES THE HIGH PRESSURE SHUTOFF VALVE IS LOCATED DIRECTLY FORWARD OF THE PRECOOLER BUT THIS IS ACTUALLY THE LOCATION OF THE PRESSURE REGULATOR VALVE. THE RPTR STATED THE MECHS INVOLVED IN THIS INCIDENT HAVE BEEN GIVEN THE ASSIGNMENT TO CORRECT THE PROC WITH ADEQUATE PICTURES TO PRECLUDE A REPEAT OF THIS INCIDENT.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.