A B757-200 incurred an in-flight engine shutdown due to loss of oil pressure and quantity. Found #5 scavenge line loose from scavenge pump. Line was not safety wired. Maintenance manual for pump change omitted safety wire.

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Attributes
ACN	718904
Time
Date	200612
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : zzz.airport
State Reference	US
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	ground : maintenance
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	maintenance : technician
Qualification	technician : powerplant technician : airframe
Experience	maintenance technician : 17
ASRS Report	718904
Person 2
Affiliation	company : air carrier
Function	maintenance : technician
Events
Anomaly	aircraft equipment problem : critical maintenance problem : improper maintenance maintenance problem : improper documentation non adherence : far
Independent Detector	aircraft equipment other aircraft equipment : #1 oil press & qty indicator other flight crewa other flight crewb
Resolutory Action	none taken : detected after the fact
Consequence	other
Factors
Maintenance	contributing factor : manuals contributing factor : work cards performance deficiency : inspection performance deficiency : installation
Supplementary
Problem Areas	Maintenance Human Performance Environmental Factor Aircraft Chart Or Publication
Primary Problem	Chart Or Publication

Narrative:

Another amt and I took a turnover from previous shift on a #1 engine lubrication and scavenge pump replacement. The old pump was still installed with all lines disconnected and ready for removal. We removed the pump and installed the new one per the amm (aircraft maintenance manual). We performed the required oil pressure test per the amm which required a high power engine run. The lead amt on duty inspected the engine during the run for leaks. No leaks were found. 2 days later the #5 bearing scavenge line nut came loose from the pump which resulted in the loss of engine oil and an ifsd. Subsequent investigation determined that the line had not been safety wired. The amm for the pump replacement does not state that the line needs to be safety wired and because we did not remove the line we did not know that it is normally safety wired. I believe the amm needs to be revised and add the step to safety wire the #5 bearing scavenge line nut in order to help prevent another ifsd.

Original NASA ASRS Text

Title: A B757-200 INCURRED AN INFLT ENG SHUTDOWN DUE TO LOSS OF OIL PRESSURE AND QUANTITY. FOUND #5 SCAVENGE LINE LOOSE FROM SCAVENGE PUMP. LINE WAS NOT SAFETY WIRED. MAINT MANUAL FOR PUMP CHANGE OMITTED SAFETY WIRE.

Narrative: ANOTHER AMT AND I TOOK A TURNOVER FROM PREVIOUS SHIFT ON A #1 ENG LUBRICATION AND SCAVENGE PUMP REPLACEMENT. THE OLD PUMP WAS STILL INSTALLED WITH ALL LINES DISCONNECTED AND READY FOR REMOVAL. WE REMOVED THE PUMP AND INSTALLED THE NEW ONE PER THE AMM (ACFT MAINT MANUAL). WE PERFORMED THE REQUIRED OIL PRESSURE TEST PER THE AMM WHICH REQUIRED A HIGH PWR ENG RUN. THE LEAD AMT ON DUTY INSPECTED THE ENG DURING THE RUN FOR LEAKS. NO LEAKS WERE FOUND. 2 DAYS LATER THE #5 BEARING SCAVENGE LINE NUT CAME LOOSE FROM THE PUMP WHICH RESULTED IN THE LOSS OF ENG OIL AND AN IFSD. SUBSEQUENT INVESTIGATION DETERMINED THAT THE LINE HAD NOT BEEN SAFETY WIRED. THE AMM FOR THE PUMP REPLACEMENT DOES NOT STATE THAT THE LINE NEEDS TO BE SAFETY WIRED AND BECAUSE WE DID NOT REMOVE THE LINE WE DID NOT KNOW THAT IT IS NORMALLY SAFETY WIRED. I BELIEVE THE AMM NEEDS TO BE REVISED AND ADD THE STEP TO SAFETY WIRE THE #5 BEARING SCAVENGE LINE NUT IN ORDER TO HELP PREVENT ANOTHER IFSD.

Data retrieved from NASA's ASRS site as of January 2009 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.