A B737-300 at termination of flight found #2 engine oil fill cap not secured and leaking.

Attributes
ACN	353763
Time
Date	199611
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : pit
State Reference	PA
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	tower : cvg
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	other personnel other
Qualification	other other : other
ASRS Report	353763
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical non adherence : far non adherence : published procedure other anomaly other
Independent Detector	other other : unspecified
Resolutory Action	other
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

On nov/xx/96, aircraft was receiving a daily check. Upon servicing the #2 engine I had noticed the lanyard (chain and ring assembly) was broken. I also noticed the oil cap was extremely difficult to remove. After attempting to re- secure the chain to the inside of the scupper. I fixed the chain in its normal position and re-secured and locked the oil cap down. Upon landing at its next destination, the pilot noticed a small puddle of oil around the #2 engine. After the cowling was opened, it was discovered that the oil cap was not properly secured in the scupper assembly. I was sure the cap was secured the previous leg and remember it well because of the problems I had with the cap removal. I cannot explain why the cap backed off but I am positive it locked and the tap secured after servicing.

Original NASA ASRS Text

Title: A B737-300 AT TERMINATION OF FLT FOUND #2 ENG OIL FILL CAP NOT SECURED AND LEAKING.

Narrative: ON NOV/XX/96, ACFT WAS RECEIVING A DAILY CHK. UPON SERVICING THE #2 ENG I HAD NOTICED THE LANYARD (CHAIN AND RING ASSEMBLY) WAS BROKEN. I ALSO NOTICED THE OIL CAP WAS EXTREMELY DIFFICULT TO REMOVE. AFTER ATTEMPTING TO RE- SECURE THE CHAIN TO THE INSIDE OF THE SCUPPER. I FIXED THE CHAIN IN ITS NORMAL POS AND RE-SECURED AND LOCKED THE OIL CAP DOWN. UPON LNDG AT ITS NEXT DEST, THE PLT NOTICED A SMALL PUDDLE OF OIL AROUND THE #2 ENG. AFTER THE COWLING WAS OPENED, IT WAS DISCOVERED THAT THE OIL CAP WAS NOT PROPERLY SECURED IN THE SCUPPER ASSEMBLY. I WAS SURE THE CAP WAS SECURED THE PREVIOUS LEG AND REMEMBER IT WELL BECAUSE OF THE PROBS I HAD WITH THE CAP REMOVAL. I CANNOT EXPLAIN WHY THE CAP BACKED OFF BUT I AM POSITIVE IT LOCKED AND THE TAP SECURED AFTER SERVICING.

Data retrieved from NASA's ASRS site as of July 2007 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.