Narrative:

On the evening of jul/wed/06; I performed a fan lube on the #1 engine of aircraft. While removing the bolts from the spinner; I noticed that 1 bolt was coming out harder than the others. After removing the bolt fully; I noticed that the threads appeared more worn than the others; so I ordered a serviceable bolt from stock and proceeded with the job. I lubed the blades and hub; installed the blades; locks; and retainers; installed the hub and torqued the hub bolts per the maintenance manual. While installing the spinner; I found that the new serviceable bolt was more difficult than normal to install into the nut plate. At that point; I installed a tap into the nut plate to clean any burrs that may have existed; installed the new serviceable bolt; and torqued all the spinner bolts to specification. At that moment; I didn't feel that there was a safety concern with the bolt that I had installed. After thinking this through for the past several days; I feel that the hub nut plate for the spinner bolt should be replaced. I have been an airline mechanic for the past 18 yrs; and have always believed that safety is the most critical part of my job. No one else was involved in the process; nor was anyone aware that I encountered any difficulty with the bolt. The inspector was called upon to witness the blade installation and the final torque of both the spinner and hub; but was also unaware of any difficulty with the bolt.

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Original NASA ASRS Text

Title: A B737-300 DURING A #1 ENG FAN BLADE LUBRICATION THE TECHNICIAN FOUND ONE SPINNER BOLT DIFFICULT TO REMOVE. CLEANED OUT NUT PLATE AND REPLACED BOLT.

Narrative: ON THE EVENING OF JUL/WED/06; I PERFORMED A FAN LUBE ON THE #1 ENG OF ACFT. WHILE REMOVING THE BOLTS FROM THE SPINNER; I NOTICED THAT 1 BOLT WAS COMING OUT HARDER THAN THE OTHERS. AFTER REMOVING THE BOLT FULLY; I NOTICED THAT THE THREADS APPEARED MORE WORN THAN THE OTHERS; SO I ORDERED A SERVICEABLE BOLT FROM STOCK AND PROCEEDED WITH THE JOB. I LUBED THE BLADES AND HUB; INSTALLED THE BLADES; LOCKS; AND RETAINERS; INSTALLED THE HUB AND TORQUED THE HUB BOLTS PER THE MAINT MANUAL. WHILE INSTALLING THE SPINNER; I FOUND THAT THE NEW SERVICEABLE BOLT WAS MORE DIFFICULT THAN NORMAL TO INSTALL INTO THE NUT PLATE. AT THAT POINT; I INSTALLED A TAP INTO THE NUT PLATE TO CLEAN ANY BURRS THAT MAY HAVE EXISTED; INSTALLED THE NEW SERVICEABLE BOLT; AND TORQUED ALL THE SPINNER BOLTS TO SPEC. AT THAT MOMENT; I DIDN'T FEEL THAT THERE WAS A SAFETY CONCERN WITH THE BOLT THAT I HAD INSTALLED. AFTER THINKING THIS THROUGH FOR THE PAST SEVERAL DAYS; I FEEL THAT THE HUB NUT PLATE FOR THE SPINNER BOLT SHOULD BE REPLACED. I HAVE BEEN AN AIRLINE MECH FOR THE PAST 18 YRS; AND HAVE ALWAYS BELIEVED THAT SAFETY IS THE MOST CRITICAL PART OF MY JOB. NO ONE ELSE WAS INVOLVED IN THE PROCESS; NOR WAS ANYONE AWARE THAT I ENCOUNTERED ANY DIFFICULTY WITH THE BOLT. THE INSPECTOR WAS CALLED UPON TO WITNESS THE BLADE INSTALLATION AND THE FINAL TORQUE OF BOTH THE SPINNER AND HUB; BUT WAS ALSO UNAWARE OF ANY DIFFICULTY WITH THE BOLT.

Data retrieved from NASA's ASRS site as of January 2009 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.