Narrative:

While completing my exterior preflight inspection; I noticed fuel leaking from the #2 engine. I notified the captain and maintenance was called. After finishing my preflight; maintenance arrived and notified us that the leak looked to be in limits; but that he will stay until departure time to continue to monitor the engine to ensure it stays within limits. We were told as the engine starts and warms; the fuel leak almost always decreases or disappears. As we pushed back and started the #2 engine; everything occurred normally and we got the thumbs up from the mechanic from the ramp. We completed our before taxi checklist and then departed for ZZZ. Upon arrival in ZZZ; ramp notified us that a clamping mechanism was attached to the #2 engine. The captain went to inspect and remove a vice grip that was attached to the engine. We concluded it was left attached from the mechanic who was monitoring the fuel leak prior to departure in ZZZ1. We also remembered that we never received a logbook entry from the observing mechanic that the fuel leak was in limits. After talking to the chief pilot (after returning the vice grip) we decided to file an as soon as possible.

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Original NASA ASRS Text

Title: B737 First Officer reported fuel leak #2 engine; requiring maintenance to inspect; subsequently aircraft departed with no log book entry being made and tools left attached to engine.

Narrative: While completing my exterior preflight inspection; I noticed fuel leaking from the #2 engine. I notified the Captain and maintenance was called. After finishing my preflight; maintenance arrived and notified us that the leak looked to be in limits; but that he will stay until departure time to continue to monitor the engine to ensure it stays within limits. We were told as the engine starts and warms; the fuel leak almost always decreases or disappears. As we pushed back and started the #2 engine; everything occurred normally and we got the thumbs up from the mechanic from the ramp. We completed our before taxi checklist and then departed for ZZZ. Upon arrival in ZZZ; ramp notified us that a clamping mechanism was attached to the #2 engine. The Captain went to inspect and remove a vice grip that was attached to the engine. We concluded it was left attached from the mechanic who was monitoring the fuel leak prior to departure in ZZZ1. We also remembered that we never received a logbook entry from the observing mechanic that the fuel leak was in limits. After talking to the Chief Pilot (after returning the vice grip) we decided to file an ASAP.

Data retrieved from NASA's ASRS site 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.