Narrative:

Cruising at FL320 in VMC; #2 engine overheat light illuminated. I called for the engine overheat checklist. After retarding engine to idle; requested lower altitude from ARTCC. Cleared to FL290 and started descent. Overheat light stayed on necessitating engine shutdown. Initiated drift-down and requested at least FL190 and it was approved. Engine was shut down and emergency declared with ARTCC. Cleared direct ZZZ and pilot's discretion to 11000 ft. Emergency information passed to ARTCC and communication established with dispatch; and maintenance discussed situation. Decided to land at ZZZ since it was nearest suitable with available drift-down altitude and time available to coordination with crew after running all checklists and coordinating with flight attendants and briefing for landing approach. Descent; approach; and landing uneventful. Cabin advisory used with flight attendants. Passenger briefed by captain. Approach flown by captain. Maintenance dispatch and duty officer briefed by captain. Supplemental information from acn 650032: maintenance had deferred one of the #2 engine fire loops prior to accepting the aircraft. During cruise flight at FL320; the #2 engine overheat annunciation illuminated. All appropriate checklists were performed in their entirety. The engine overheat annunciation did not extinguish after operating the engine at idle for 30 seconds. Callback conversation with reporter acn 650031 revealed the following information: the reporter stated the maintenance action taken and the failed component is unknown. Callback conversation with reporter acn 650032 revealed the following information: no maintenance report to crew and has no idea what fixed the airplane.

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Original NASA ASRS Text

Title: A B737-500 AT FL320 DECLARED AN EMER AND DIVERTED DUE TO #2 ENG OVERHEAT WARNING. ENG SHUTDOWN AFTER CHKLISTS COMPLETED.

Narrative: CRUISING AT FL320 IN VMC; #2 ENG OVERHEAT LIGHT ILLUMINATED. I CALLED FOR THE ENG OVERHEAT CHKLIST. AFTER RETARDING ENG TO IDLE; REQUESTED LOWER ALT FROM ARTCC. CLRED TO FL290 AND STARTED DSCNT. OVERHEAT LIGHT STAYED ON NECESSITATING ENG SHUTDOWN. INITIATED DRIFT-DOWN AND REQUESTED AT LEAST FL190 AND IT WAS APPROVED. ENG WAS SHUT DOWN AND EMER DECLARED WITH ARTCC. CLRED DIRECT ZZZ AND PLT'S DISCRETION TO 11000 FT. EMER INFO PASSED TO ARTCC AND COM ESTABLISHED WITH DISPATCH; AND MAINT DISCUSSED SIT. DECIDED TO LAND AT ZZZ SINCE IT WAS NEAREST SUITABLE WITH AVAILABLE DRIFT-DOWN ALT AND TIME AVAILABLE TO COORD WITH CREW AFTER RUNNING ALL CHKLISTS AND COORDINATING WITH FLT ATTENDANTS AND BRIEFING FOR LNDG APCH. DSCNT; APCH; AND LNDG UNEVENTFUL. CABIN ADVISORY USED WITH FLT ATTENDANTS. PAX BRIEFED BY CAPT. APCH FLOWN BY CAPT. MAINT DISPATCH AND DUTY OFFICER BRIEFED BY CAPT. SUPPLEMENTAL INFO FROM ACN 650032: MAINT HAD DEFERRED ONE OF THE #2 ENG FIRE LOOPS PRIOR TO ACCEPTING THE ACFT. DURING CRUISE FLT AT FL320; THE #2 ENG OVERHEAT ANNUNCIATION ILLUMINATED. ALL APPROPRIATE CHKLISTS WERE PERFORMED IN THEIR ENTIRETY. THE ENG OVERHEAT ANNUNCIATION DID NOT EXTINGUISH AFTER OPERATING THE ENG AT IDLE FOR 30 SECONDS. CALLBACK CONVERSATION WITH RPTR ACN 650031 REVEALED THE FOLLOWING INFO: THE RPTR STATED THE MAINT ACTION TAKEN AND THE FAILED COMPONENT IS UNKNOWN. CALLBACK CONVERSATION WITH RPTR ACN 650032 REVEALED THE FOLLOWING INFO: NO MAINT RPT TO CREW AND HAS NO IDEA WHAT FIXED THE AIRPLANE.

Data retrieved from NASA's ASRS site as of January 2009 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.