B767-300 and 300 ER
Maintenance Airframe; Maintenance Powerplant
Confusion
Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Equipment / Tooling; Human Factors
I was working as part of an Engine Field Service team working a chronic 'No Start' and Engine Fuel Valve problem. I was involved in trouble shooting the problem and helping replace the [wiring] harness from the Engine Firewall and also various other trouble shooting tasks. On a July day; 2012; I completed the reinstallation of the J-Box (Junction Box) top cover and in the process used a 1/4' - 5/16' inch Ratchet Ring wrench. When I had finished this job; I went upstairs and cleaned the Spanner [wrench] and had lunch. Later that evening before we finished for the night; I asked a fellow Mechanic to pass me the said wrench and we could not find it. A brief search of my tool box; clothing; engine and cabin was carried out and we could not find the wrench. As it had been a long day we went to the hotel and would complete a thorough search in the morning. We returned the next morning and carried out a thorough search of the engine. Four mechanics spent in excess of one hour and as much as two hours searching the engine using lights; mirrors and magnetic pick-up tools in the area above the heat shield. We also checked tool box and cabin again and the ramp area.  We accomplished a 'Dry Motor' [engine rotation using air] with cowlings open to try to see if we could hear the wrench move.  We then accomplished a series of six Engine runs over several hours as part of our Checks. We then opened cowls and searched again to ensure wrench was not there and if it was; if the [Engine] runs had moved its' position. Approximately five hours later; I called Maintenance Control Engine desk and informed them of everything that we had done. I told them that I was unable to say for certain where the wrench was; but that we had done everything that we could to ensure it was not on the engine; but that I could not for certain say that it was not there. I asked that at the end of the Ferry Flight; that another search be accomplished in case the wrench was still in the engine and had now moved.
A Line Mechanic working a chronic 'No-Start' and Engine Fuel Valve problem on a B767-300 aircraft describes the efforts of four mechanics and himself to locate a misplaced ratchet ring type wrench that was used during the reinstallation of an Engine J-Box cover.