Narrative:

During a routine inspection and calibration of the torque multipliers used on the aft engine mount bolts for the PW4000 (small) engines, it was found that the wrong handle was used with the torque multiplier. Although the handles are interchangeable, the torque tables on the handles are different between the 392 and 393-a torque multipliers. Therefore, the input torques will give a different output torque when the handle label is not matched to the proper torque multiplier. Since oct/01, approximately 50 engines were produced from our engine shop. It is not known how many of those engines may have had the aft mount bolts 'under torqued' because of this mix-up. Air carrier X management has been advised of the problem and has taken the necessary steps to correct any discrepancies in this process. Job cards are being modified with notes to observe this problem. The 392 torque multipliers have been locked up to prevent inadvertent use with the wrong torque guide on the 393 handle, and color coding of the handle and multiplier will be established.

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Original NASA ASRS Text

Title: A SHOP TECHNICIAN RPTS USING THE WRONG TORQUE MULTIPLIER HANDLE AND MAY HAVE RELEASED ENGS WITH THE INCORRECT TORQUE ON AFT MOUNT BOLTS.

Narrative: DURING A ROUTINE INSPECTION AND CALIBRATION OF THE TORQUE MULTIPLIERS USED ON THE AFT ENG MOUNT BOLTS FOR THE PW4000 (SMALL) ENGS, IT WAS FOUND THAT THE WRONG HANDLE WAS USED WITH THE TORQUE MULTIPLIER. ALTHOUGH THE HANDLES ARE INTERCHANGEABLE, THE TORQUE TABLES ON THE HANDLES ARE DIFFERENT BTWN THE 392 AND 393-A TORQUE MULTIPLIERS. THEREFORE, THE INPUT TORQUES WILL GIVE A DIFFERENT OUTPUT TORQUE WHEN THE HANDLE LABEL IS NOT MATCHED TO THE PROPER TORQUE MULTIPLIER. SINCE OCT/01, APPROX 50 ENGS WERE PRODUCED FROM OUR ENG SHOP. IT IS NOT KNOWN HOW MANY OF THOSE ENGS MAY HAVE HAD THE AFT MOUNT BOLTS 'UNDER TORQUED' BECAUSE OF THIS MIX-UP. ACR X MGMNT HAS BEEN ADVISED OF THE PROB AND HAS TAKEN THE NECESSARY STEPS TO CORRECT ANY DISCREPANCIES IN THIS PROCESS. JOB CARDS ARE BEING MODIFIED WITH NOTES TO OBSERVE THIS PROB. THE 392 TORQUE MULTIPLIERS HAVE BEEN LOCKED UP TO PREVENT INADVERTENT USE WITH THE WRONG TORQUE GUIDE ON THE 393 HANDLE, AND COLOR CODING OF THE HANDLE AND MULTIPLIER WILL BE ESTABLISHED.

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.