Narrative:

On jan/xa/99, I removed an integrated drive generator on #2 engine on aircraft xyz for replacement of the carbon seal. The carbon seal is supposed to have a packing around it. The mechanic I was working with thought I installed this packing and I thought he had installed it. The packing was never installed. The carbon seal was then installed and the integrated drive generator installed after that. No leaks were detected on any engine motoring or any prior flts. The aircraft was released on feb/xa/99 and an oil loss was detected on a flight from ZZZ to XXX and the engine was shut down and the flight diverted.

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Original NASA ASRS Text

Title: A B747-400 IN CRUISE DIVERTED DUE TO LOSS OF OIL IN #2 ENG CAUSED BY A PACKING OMITTED FROM THE #2 INTEGRATED DRIVE GENERATOR CARBON SEAL DURING INSTALLATION.

Narrative: ON JAN/XA/99, I REMOVED AN INTEGRATED DRIVE GENERATOR ON #2 ENG ON ACFT XYZ FOR REPLACEMENT OF THE CARBON SEAL. THE CARBON SEAL IS SUPPOSED TO HAVE A PACKING AROUND IT. THE MECH I WAS WORKING WITH THOUGHT I INSTALLED THIS PACKING AND I THOUGHT HE HAD INSTALLED IT. THE PACKING WAS NEVER INSTALLED. THE CARBON SEAL WAS THEN INSTALLED AND THE INTEGRATED DRIVE GENERATOR INSTALLED AFTER THAT. NO LEAKS WERE DETECTED ON ANY ENG MOTORING OR ANY PRIOR FLTS. THE ACFT WAS RELEASED ON FEB/XA/99 AND AN OIL LOSS WAS DETECTED ON A FLT FROM ZZZ TO XXX AND THE ENG WAS SHUT DOWN AND THE FLT DIVERTED.

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.