Narrative:

On oct/xa/99, I was pulled off live flight gates to try to return to service a B767 that had a disintegrated left engine hydraulic pump. I was told to go help 2 other technicians finish up tightening up a few hoses, filter housings, and the actual pump. Upon arrival to the aircraft, the technicians were almost done and was directed to the cockpit to get ready for an engine run. I proceeded to motor and then run the left engine per the taxi/start-up checklist except omitted to check the logbook. At the time, I found it not of great concern but later found out that this job was a prior shift turnover. The job was turned over to 4 different people before we started working on it. Per the maintenance manual we were to check the hydraulic filter for contamination. Upon removing the housing we found out there were no filters installed. Nobody had said anything to us. After the incident I looked through the logbook and saw an item that read 'case drain and pressure filters removed, housing installed loosely.' this is a perfect example of communication breakdown. Although the item was in the logbook, it should have been reiterated that the filters were not installed. All of the mechanics involved are of good maintenance judgement. This incident is just a natural human error.

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Original NASA ASRS Text

Title: A B767-300 INCURRED HYD SYS DAMAGE WHEN THE L SYS WAS OPERATED TO TEST A REPLACEMENT ENG DRIVEN PUMP WITH NO FILTERS INSTALLED.

Narrative: ON OCT/XA/99, I WAS PULLED OFF LIVE FLT GATES TO TRY TO RETURN TO SVC A B767 THAT HAD A DISINTEGRATED L ENG HYD PUMP. I WAS TOLD TO GO HELP 2 OTHER TECHNICIANS FINISH UP TIGHTENING UP A FEW HOSES, FILTER HOUSINGS, AND THE ACTUAL PUMP. UPON ARR TO THE ACFT, THE TECHNICIANS WERE ALMOST DONE AND WAS DIRECTED TO THE COCKPIT TO GET READY FOR AN ENG RUN. I PROCEEDED TO MOTOR AND THEN RUN THE L ENG PER THE TAXI/START-UP CHKLIST EXCEPT OMITTED TO CHK THE LOGBOOK. AT THE TIME, I FOUND IT NOT OF GREAT CONCERN BUT LATER FOUND OUT THAT THIS JOB WAS A PRIOR SHIFT TURNOVER. THE JOB WAS TURNED OVER TO 4 DIFFERENT PEOPLE BEFORE WE STARTED WORKING ON IT. PER THE MAINT MANUAL WE WERE TO CHK THE HYD FILTER FOR CONTAMINATION. UPON REMOVING THE HOUSING WE FOUND OUT THERE WERE NO FILTERS INSTALLED. NOBODY HAD SAID ANYTHING TO US. AFTER THE INCIDENT I LOOKED THROUGH THE LOGBOOK AND SAW AN ITEM THAT READ 'CASE DRAIN AND PRESSURE FILTERS REMOVED, HOUSING INSTALLED LOOSELY.' THIS IS A PERFECT EXAMPLE OF COM BREAKDOWN. ALTHOUGH THE ITEM WAS IN THE LOGBOOK, IT SHOULD HAVE BEEN REITERATED THAT THE FILTERS WERE NOT INSTALLED. ALL OF THE MECHS INVOLVED ARE OF GOOD MAINT JUDGEMENT. THIS INCIDENT IS JUST A NATURAL HUMAN ERROR.

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.