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A lead mechanic working a B737-800 aircraft noticed 1/8 inch radial play at the accessory gearbox (agb) lower clevis mount on a nexgen cfm-56-7 engine. Although no wear limits could be found; he was told by company engineering and their engine support desk he could defer the wear. The engine was replaced the following night for excessive bushing wear.
| Attributes | |
| ACN | 1008834 |
| Time | |
| Date | 201204 |
| Local Time Of Day | 0001-0600 |
| Place | |
| Locale Reference | ZZZ.Airport |
| State Reference | US |
| Environment | |
| Light | Night |
| Aircraft 1 | |
| Make Model Name | B737-800 |
| Operating Under FAR Part | Part 121 |
| Flight Phase | Parked |
| Component | |
| Aircraft Component | Accessory Drive Section |
| Person 1 | |
| Function | Lead Technician |
| Qualification | Maintenance Airframe Maintenance Powerplant |
| Experience | Maintenance Lead Technician 3 Maintenance Technician 25 |
| Events | |
| Anomaly | Aircraft Equipment Problem Critical |
Narrative:
Non-routine [write-up]; #1 engine accessory gearbox (agb) lower clevis mount has excessive play. I let supervisor know about the problem; and then we both started to look into the limits. I could not find any limits for the lower clevis mount rod [link] in the aircraft maintenance manual (amm). The supervisor then told me he had found an engineering repair order (ero) for another airplane with the same problem as this one. After measuring the looseness; we had 1/8 of an inch play. Then I was told that engineering and the engine desk both said I didn't need an ero for the aircraft and that I could make a deferral per amm 72-63-00-200. I called the engine desk and he said to defer it under agb housing for damage. I did not feel this was the right way to go; but I was unable to find any other limits for the clevis rod; so [with] the assurance of both engineering and the engine desk knowing what we had; I went ahead and placed it on a deferral per amm 72-63-00-200.
Original NASA ASRS Text
Title: A Lead Mechanic working a B737-800 aircraft noticed 1/8 inch radial play at the Accessory Gearbox (AGB) Lower clevis mount on a NexGen CFM-56-7 engine. Although no wear limits could be found; he was told by company Engineering and their Engine Support desk he could defer the wear. The engine was replaced the following night for excessive bushing wear.
Narrative: Non-Routine [write-up]; #1 Engine Accessory Gearbox (AGB) lower clevis mount has excessive play. I let Supervisor know about the problem; and then we both started to look into the limits. I could not find any limits for the lower clevis mount rod [link] in the Aircraft Maintenance Manual (AMM). The Supervisor then told me he had found an Engineering Repair Order (ERO) for another airplane with the same problem as this one. After measuring the looseness; we had 1/8 of an inch play. Then I was told that Engineering and the Engine desk both said I didn't need an ERO for the aircraft and that I could make a deferral per AMM 72-63-00-200. I called the Engine desk and he said to defer it under AGB Housing for damage. I did not feel this was the right way to go; but I was unable to find any other limits for the clevis rod; so [with] the assurance of both Engineering and the Engine desk knowing what we had; I went ahead and placed it on a deferral per AMM 72-63-00-200.
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.