Narrative:

When we arrived at the plane; maintenance was working on a problem with the left pack. Early indications were that it was a repeat item and they could not fix it and we began looking into the possibility of flying single pack. The MEL prohibits ETOPS operations single pack. The log book sign off was 'left pack flow control valve excercised (sic) and pack operation normal as amm 21-51-01' the captain questioned what they had done to fix the problem. We were told they had lubricated the valve and mechanical linkage; and that fixed the problem. We were assured it was fixed; but the electronic logbook said the 'valve has an intermittent fault.' we experienced the same problem on arrival at a domestic airport. After landing; I opened the crossfeed valve and the pack started working. Our logbook entry indicated this. I discussed the situation with maintenance at that time and my opinion that the pack valve was clearly not the problem; but probably an engine bleed problem. The mechanic told me he knew it was not the valve; but he was being ordered to replace the valve again. This airline should only operate aircraft that are in a safe and legal condition. Mechanics lying to flight crew should not be tolerated. Line mechanics should be permitted (or required) to solve the actual problem with the plane; not just the quickest thing to give the illusion the problem was fixed so the plane can operate the next revenue flight. Any and all management persons who approved or coerced others to release an airplane into revenue service when they knew; or should have known; that the problem was not fixed should be terminated. Maintenance assured flight crew the plane was fixed; when they knew it was not.

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Original NASA ASRS Text

Title: A pilot reported that his Company ordered a Mechanic to lubricate a B767-300 pack valve when he knew an engine bleed valve was the most probable cause of a repeat pressurization problem.

Narrative: When we arrived at the plane; Maintenance was working on a problem with the left pack. Early indications were that it was a repeat item and they could not fix it and we began looking into the possibility of flying single pack. The MEL prohibits ETOPS operations single pack. The log book sign off was 'LEFT PACK FLOW CONTROL VALVE EXCERCISED (sic) AND PACK OPERATION NORMAL AS AMM 21-51-01' The Captain questioned what they had done to fix the problem. We were told they had lubricated the valve and mechanical linkage; and that fixed the problem. We were assured it was fixed; but the electronic logbook said the 'VALVE HAS AN INTERMITTENT FAULT.' We experienced the same problem on arrival at a domestic airport. After landing; I opened the crossfeed valve and the pack started working. Our logbook entry indicated this. I discussed the situation with Maintenance at that time and my opinion that the pack valve was clearly not the problem; but probably an engine bleed problem. The Mechanic told me he knew it was not the valve; but he was being ordered to replace the valve again. This Airline should only operate aircraft that are in a safe and legal condition. Mechanics lying to flight crew should not be tolerated. Line Mechanics should be permitted (or required) to solve the actual problem with the plane; not just the quickest thing to give the illusion the problem was fixed so the plane can operate the next revenue flight. Any and all management persons who approved or coerced others to release an airplane into revenue service when they knew; or should have known; that the problem was not fixed should be terminated. Maintenance assured flight crew the plane was fixed; when they knew it was not.

Data retrieved from NASA's ASRS site as of July 2013 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.