Narrative:

The work release item to be worked on had been carried for 30 days. It was the replacement of the forward east&east door seal. The door was removed and taken inside. A mistake was noticed that the seal was marked by the manufacturer as forward and aft. Consequently the seal was removed and the process started again. The east&east door seal removal and installation should have a section under chapter zz dedicated to itself. Instead it is found under flap seals in the boeing maintenance manual. Flap seals have nothing to correlate in design with the left shaped seal designed for the east&east door. Page XXX states on installation, insert the longer flange surface of the seal into the inboard side of the retainer. Also you must insert the shorter flange surface of the seal into the outboard side of the retainer. The problem is the east&east has an upper and lower retaining groove. It would have been prudent for the seal manufacturer to have not only printed forward and aft on the seal but, to have also printed up and down for clarity of installation. The ipc illustration is not clear on a picture of the seal either. Step 6 on page XXX which completes the job states, 'to make sure the flap seal touches the door smoothly and equally.' this is referring to a flap seal on a main entry door of an aircraft. With the east&east door seal, this would happen even if the seal were put in incorrectly. Also the final step does not call out for a pressurization check for this or any other seal in chapter zz. Mistakes could only be found once airborne. Another important note: boeing maintenance manual for the B737-300 series aircraft states for reinstalling the east&east door the following: 'to test the door warning system per page BBB.' again a reference to a pressurization check is not called for.

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Original NASA ASRS Text

Title: B737-300 ELECTRICAL AND ELECTRONICS COMPARTMENT DOOR SEAL REPLACEMENT INSTRUCTIONS IN THE MAINT MANUAL ARE INADEQUATE.

Narrative: THE WORK RELEASE ITEM TO BE WORKED ON HAD BEEN CARRIED FOR 30 DAYS. IT WAS THE REPLACEMENT OF THE FORWARD E&E DOOR SEAL. THE DOOR WAS REMOVED AND TAKEN INSIDE. A MISTAKE WAS NOTICED THAT THE SEAL WAS MARKED BY THE MANUFACTURER AS FORWARD AND AFT. CONSEQUENTLY THE SEAL WAS REMOVED AND THE PROCESS STARTED AGAIN. THE E&E DOOR SEAL REMOVAL AND INSTALLATION SHOULD HAVE A SECTION UNDER CHAPTER ZZ DEDICATED TO ITSELF. INSTEAD IT IS FOUND UNDER FLAP SEALS IN THE BOEING MAINT MANUAL. FLAP SEALS HAVE NOTHING TO CORRELATE IN DESIGN WITH THE L SHAPED SEAL DESIGNED FOR THE E&E DOOR. PAGE XXX STATES ON INSTALLATION, INSERT THE LONGER FLANGE SURFACE OF THE SEAL INTO THE INBOARD SIDE OF THE RETAINER. ALSO YOU MUST INSERT THE SHORTER FLANGE SURFACE OF THE SEAL INTO THE OUTBOARD SIDE OF THE RETAINER. THE PROB IS THE E&E HAS AN UPPER AND LOWER RETAINING GROOVE. IT WOULD HAVE BEEN PRUDENT FOR THE SEAL MANUFACTURER TO HAVE NOT ONLY PRINTED FORWARD AND AFT ON THE SEAL BUT, TO HAVE ALSO PRINTED UP AND DOWN FOR CLARITY OF INSTALLATION. THE IPC ILLUSTRATION IS NOT CLR ON A PICTURE OF THE SEAL EITHER. STEP 6 ON PAGE XXX WHICH COMPLETES THE JOB STATES, 'TO MAKE SURE THE FLAP SEAL TOUCHES THE DOOR SMOOTHLY AND EQUALLY.' THIS IS REFERRING TO A FLAP SEAL ON A MAIN ENTRY DOOR OF AN ACFT. WITH THE E&E DOOR SEAL, THIS WOULD HAPPEN EVEN IF THE SEAL WERE PUT IN INCORRECTLY. ALSO THE FINAL STEP DOES NOT CALL OUT FOR A PRESSURIZATION CHK FOR THIS OR ANY OTHER SEAL IN CHAPTER ZZ. MISTAKES COULD ONLY BE FOUND ONCE AIRBORNE. ANOTHER IMPORTANT NOTE: BOEING MAINT MANUAL FOR THE B737-300 SERIES ACFT STATES FOR REINSTALLING THE E&E DOOR THE FOLLOWING: 'TO TEST THE DOOR WARNING SYS PER PAGE BBB.' AGAIN A REF TO A PRESSURIZATION CHK IS NOT CALLED FOR.

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.