Narrative:

Engine south/north XXXX-48 on a dhc-8-100 aircraft had an overtorque. Engine was changed; as instructed by my lead mechanic; who was instructed by engine program manager. We removed reduction gearbox rgb 120306 from engine XXXX-48 and sent it out for inspection. We then installed reduction gearbox rgb (YYYY-24) on engine XXXX-48. Engine was signed-in february; 2014. Don't know when engine was installed; but when [mistake was] discovered ten days later; the aircraft came to ZZZ to change engine. Overtorque was 168.3%. My lead and myself checked manual and found that the overtorque was [actually] 'out of limits'; but that was after program manager came to shop on that day. Neither one of us ever checked the manual; just took manager's word that turbo machine [engine] south/north XXXX-48 was serviceable. Engine program manager came to shop and asked about the engine; he wanted to send engine out. Lead mechanic told program manager [that] engine is [already] on aircraft. Lack of communication between engine program manager and lead mechanic. I knew it was [originally] an overtorque; but never asked how much. My lead showed me the paper ten days [after the rgb change] that showed [an overtorque] at 168.3%. If I would have [previously] asked how much [overtorque]; a light would go off; that's a lot; lets check manual. The engine was changed at ZZZ. Myself and my lead should not take anyone's word that an overtorqued engine is serviceable; we both need to check the manual before; not after the fact.

Related reports:

Google
 

Original NASA ASRS Text

Title: An Aircraft Maintenance Technician (AMT) describes how a lack of communication between his Lead Mechanic and their Engine Program Manager contributed to their replacing a Reduction Gearbox (RGB) on a PW 120 engine that had overtorqued; instead of removing the engine from a DHC-8-100 aircraft.

Narrative: Engine S/N XXXX-48 on a DHC-8-100 aircraft had an overtorque. Engine was changed; as instructed by my Lead Mechanic; who was instructed by Engine Program Manager. We removed Reduction Gearbox RGB 120306 from Engine XXXX-48 and sent it out for inspection. We then installed Reduction Gearbox RGB (YYYY-24) on Engine XXXX-48. Engine was signed-in February; 2014. Don't know when engine was installed; but when [mistake was] discovered ten days later; the aircraft came to ZZZ to change engine. Overtorque was 168.3%. My Lead and myself checked manual and found that the overtorque was [actually] 'Out of Limits'; but that was after Program Manager came to Shop on that day. Neither one of us ever checked the manual; just took Manager's word that turbo machine [Engine] S/N XXXX-48 was serviceable. Engine Program Manager came to Shop and asked about the engine; he wanted to send engine out. Lead Mechanic told Program Manager [that] engine is [already] on aircraft. Lack of communication between Engine Program Manager and Lead Mechanic. I knew it was [originally] an overtorque; but never asked how much. My Lead showed me the paper ten days [after the RGB change] that showed [an overtorque] at 168.3%. If I would have [previously] asked how much [overtorque]; a light would go off; that's a lot; lets check manual. The engine was changed at ZZZ. Myself and my Lead should not take anyone's word that an overtorqued engine is serviceable; we both need to check the manual before; not after the fact.

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.