Narrative:

Aircraft X as a through flight. Total ground time was 1 hour. It had an inbound write up with radio distance magnetic indicator (RDMI) issues and cabin outflow valves issues. Simultaneously two technicians were tasked to help me with assigned work. Number 2 engine call out chip detectors. As I worked the write up; the technicians were starting lockout tag out (loto) for number 2.job card open and subsystem deactivation. After I finished rmdi; I went downstairs to assist the technicians. Loto of leading edge and loto of reverser; magnetic chip detector (mcd) removal *(note singular mcd annotated). Previously quality control was contacted informing them we would need an inspector for mcds. Inspection acknowledged task; but informed us; 'due to [the] maintenance manual' he would need to 'verify replacement of o-rings' on the mcds. He would expect to see new o-rings installed on all mcds.job card: engine magnetic chip detectors - inspect *(note multiple mcd's annotated). This job card states; 'if the packing has damage; discard the packing; lubricate new packing and install on mcd probe. But maintenance manual supersedes this. We had trouble finding the correct o-rings. I had our dedicated parts desk guy locate and order the o-rings (4) for scavenge pump from ipc fig 79-21-04-05. He ordered item 76; which was part number (P/north) AS3209-009. 5th mcd checked engine oil tank; P/north found in engine ipc 71-00-01-422 item 723. 6th mcd checked gearbox P/north found in engine ipc 72-61-00-023 item 316 mcd's check accomplished; replaced all O rings; require inspection item signed off. Job card [for] close and subsystem activation accomplished.next night same callout different 767-300. My lead kept old paperwork used to order P/north's for mcd o-rings. Two new technicians; told by lead to research P/north since quality control will want to 'verify they were changed.' lead still had engine ipc paperwork from yesterday. After tech's researched part numbers; the lead asked them to compare numbers. They duplicated the 5th and 6th o-rings as correct P/north's; but the (4) scavenge pump o-rings conflicted with the ones ordered; installed on the day before. Lead contacted supervisor; operation manager and had small discussion. Aircraft X; actually came in and left [the] second day.operations manager called engine desk; after some research; engineer determined o-ring made of same material; but was more likely to be a tenth of a thousand smaller than the correct size. Noted number 2 engine serviced but no oil added previous trips. He alerted the station plane is inbound and change to correct o-rings; inspect; and check for leaks.suggestions: follow up meeting with operations manager at shift briefing. Planers may see paperwork with only one mcd call out and think easy task; but not see the big picture; 767-300 engine work requires extensive loto of leading edge and thrust reversers; and manpower. Maintenance manual mcd check says inspect o-rings for damage; if no damage reinstall; required inspection item says otherwise! Six mcd serviced; time-consuming task; labor intensive; should not be done on a through flight; but maybe overnight maintenance. Operations manager said he would inform other supervisors to allot three technicians for mcd checks on 767's.

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Original NASA ASRS Text

Title: B767 Maintenance Technician reported that an incorrect O-ring was installed on the engine's oil Magnetic Chip Detector.

Narrative: Aircraft X as a through flight. Total ground time was 1 hour. It had an inbound write up with Radio Distance Magnetic Indicator (RDMI) issues and Cabin outflow valves issues. Simultaneously two technicians were tasked to help me with assigned work. Number 2 engine call out chip detectors. As I worked the write up; the technicians were starting Lockout Tag out (LOTO) for Number 2.Job Card Open and subsystem deactivation. After I finished RMDI; I went downstairs to assist the technicians. LOTO of Leading Edge and LOTO of reverser; Magnetic Chip Detector (MCD) Removal *(note singular MCD annotated). Previously Quality Control was contacted informing them we would need an inspector for MCDs. Inspection acknowledged task; but informed us; 'due to [the] Maintenance Manual' He would need to 'VERIFY REPLACEMENT OF O-RINGS' on the MCDs. He would expect to see new O-rings installed on all MCDs.Job Card: ENGINE MAGNETIC CHIP DETECTORS - INSPECT *(Note MULTIPLE MCD's annotated). This Job Card states; 'If the packing has damage; discard the packing; lubricate new packing and install on MCD probe. But Maintenance Manual supersedes this. We had trouble finding the correct O-rings. I had our dedicated parts desk guy locate and order the O-rings (4) for Scavenge Pump from IPC Fig 79-21-04-05. He ordered item 76; which was Part Number (P/N) AS3209-009. 5th MCD Checked engine oil tank; P/N found in Engine IPC 71-00-01-422 Item 723. 6th MCD Checked gearbox P/N found in Engine IPC 72-61-00-023 item 316 MCD's check accomplished; Replaced all O rings; Require Inspection Item signed off. Job Card [for] close and subsystem activation accomplished.Next night same callout different 767-300. My Lead kept old paperwork used to order P/N's for MCD O-rings. Two new technicians; told by Lead to research P/N since Quality Control will want to 'verify they were changed.' Lead still had Engine IPC paperwork from yesterday. After Tech's researched part numbers; the Lead asked them to compare numbers. They duplicated the 5th and 6th O-rings as correct P/N's; but the (4) Scavenge Pump O-rings conflicted with the ones ordered; installed on the day before. Lead contacted Supervisor; Operation Manager and had small discussion. Aircraft X; actually came in and left [the] second day.Operations Manager called Engine Desk; after some research; engineer determined O-ring made of same material; but was more likely to be a tenth of a thousand smaller than the correct size. Noted Number 2 engine serviced but no oil added previous trips. He alerted the station plane is inbound and change to correct O-rings; inspect; and check for leaks.Suggestions: Follow up meeting with Operations Manager at shift briefing. Planers may see paperwork with only one MCD call out and think easy task; but not see the big picture; 767-300 engine work requires extensive LOTO of Leading Edge and Thrust Reversers; and Manpower. Maintenance Manual MCD check says inspect O-rings for damage; if no damage reinstall; Required Inspection Item says otherwise! Six MCD serviced; Time-consuming Task; Labor intensive; should not be done on a through flight; but maybe overnight maintenance. Operations Manager said he would inform other Supervisors to allot three Technicians for MCD checks on 767's.

Data retrieved from NASA's ASRS site 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.