A mechanic and inspector report about a pilot finding a fuel leak in the left wing of a B737-300 dur...

Narrative:

Aircraft came in for a B/C check. I and two fellow mechanics were assigned left wing. That night we had a down stop inspection on leading edge slat tracks. During the inspector's inspection; he found #2 slat inboard (inbd) track down-stop locator installed incorrectly. So after gathering the parts; we proceeded to change the locator per maintenance manual (MM). Myself and another mechanic removed and replaced the locator per maintenance manual. We are 100% confident that maintenance was 100% compliant when we got done per maintenance manual and inspection.I was informed that on pre-flight inspection; the pilot found a fuel leak on the left wing. After further investigation; it was found that the #2 slat inboard track can had a puncture. After they removed the slat they found a suspect washer in the slat track that possibly could have punctured the can. The washer found had nothing to do with the down-stop locator we changed. Once again we feel 100% confident that there was nothing we did wrong that could have punctured the slat track can the way it did.

Original NASA ASRS Text

Title: A Mechanic and Inspector report about a Pilot finding a fuel leak in the left wing of a B737-300 during his preflight at the #2 slat inboard track can. A washer was found in the slat can.

Narrative: Aircraft came in for a B/C Check. I and two fellow Mechanics were assigned left wing. That night we had a down stop inspection on leading edge slat tracks. During the Inspector's inspection; he found #2 slat inboard (INBD) track down-stop locator installed incorrectly. So after gathering the parts; we proceeded to change the locator per Maintenance Manual (MM). Myself and another Mechanic removed and replaced the locator per Maintenance Manual. We are 100% confident that maintenance was 100% compliant when we got done per Maintenance Manual and Inspection.I was informed that on pre-flight inspection; the Pilot found a fuel leak on the left wing. After further investigation; it was found that the #2 slat inboard track can had a puncture. After they removed the slat they found a suspect washer in the slat track that possibly could have punctured the can. The washer found had nothing to do with the down-stop locator we changed. Once again we feel 100% confident that there was nothing we did wrong that could have punctured the slat track can the way it did.

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.

Attributes
ACN	890257
Time
Date	201004
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Night
Aircraft 1
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	Parked
Component
Aircraft Component	Fuel Tank
Person 1
Function	Technician
Qualification	Maintenance Airframe Maintenance Powerplant
Person 2
Function	Inspector
Qualification	Maintenance Powerplant Maintenance Airframe
Events
Anomaly	Aircraft Equipment Problem Critical

A mechanic and inspector report about a pilot finding a fuel leak in the left wing of a B737-300 during his preflight at the #2 slat inboard track can. A washer was found in the slat can.