Narrative:

I was sent as inspector on a couple of fuel leak repairs. Fuel was leaking from the back of the left wing in the area of the trunnion and over the #2 engine. This was an ongoing repair that I became involved with on the third day. The contract company doing the actual work in the wing was out. When I got there they were cleaning out the prior attempts at sealing the tanks. They cleaned and resealed and did the negative pressure checks and found the leaks to be sealed. I then went in to give the ok to close and found the tanks to be clean of debris and no remaining FOD or visible contaminants; so I gave the ok to close. After closing the tanks; we transferred fuel using a ground power cart and did notice some indication fluctuations and saw the volts low from the cart. We started the APU and all the indications went to normal. There were no further leaks; so we completed the paperwork and notified maintenance contractors it was a good aircraft and (we) returned home. When the aircraft flew; it had fuel indication trouble and was removed from service. They found the fuel contaminated and cleaned the tanks and probes to fix the situation. The tanks had been entered and sealed a couple of times before I got to it. I cannot say what may or may not have entered the tanks before I got there; but I do know they were clean and dry when I said to close them.

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Original NASA ASRS Text

Title: An Aircraft Inspector inspected fuel tanks for left wing rear spar in the areas of the main landing gear trunnion and over the #2 engine. The B737-300 was later removed from service for fuel tank indication problems; fuel was found contaminated affecting the fuel probes.

Narrative: I was sent as inspector on a couple of fuel leak repairs. Fuel was leaking from the back of the left wing in the area of the trunnion and over the #2 engine. This was an ongoing repair that I became involved with on the third day. The contract company doing the actual work in the wing was out. When I got there they were cleaning out the prior attempts at sealing the tanks. They cleaned and resealed and did the negative pressure checks and found the leaks to be sealed. I then went in to give the OK to close and found the tanks to be clean of debris and no remaining FOD or visible contaminants; so I gave the OK to close. After closing the tanks; we transferred fuel using a ground power cart and did notice some indication fluctuations and saw the volts low from the cart. We started the APU and all the indications went to normal. There were no further leaks; so we completed the paperwork and notified Maintenance Contractors it was a good aircraft and (we) returned home. When the aircraft flew; it had fuel indication trouble and was removed from service. They found the fuel contaminated and cleaned the tanks and probes to fix the situation. The tanks had been entered and sealed a couple of times before I got to it. I cannot say what may or may not have entered the tanks before I got there; but I do know they were clean and dry when I said to close them.

Data retrieved from NASA's ASRS site as of April 2012 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.