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.