Narrative:

Scheduled to fly with an APU generator inoperative. Problems with the left generator cycling on and off during engine start and when pulling external power. ZZZZ maintenance come on board; we restarted left motor; aircraft X mechanic cycled electric power many times between external/generator #1/generator #2. ZZZZ maintenance; myself; first officer's; maintenance and dispatch all were convinced that all was ok. Received new release; added fuel and departed. About 3 hours into flight; right generator dropped off line. Many EICAS messages. Right generator; right bus tie isolated. Right engine eec off. Declared emergency; recalled first officer to cockpit. Divert to ZZZZ. We chose ZZZZ over ZZZZ2 because of a longer runway; listed as primary diversion airport in fom; note in fom for ZZZZ2 deep ditches located at both ends of runway and talking to air carrier Y who informed us he was over ZZZZ and the WX was perfect. Also the first officer had been in ZZZZ before. We had some problems understanding ATC. Using my emergency authority/authorized I invited a current air carrier Z captain into the cockpit to help with communication and his knowledge of ZZZZ. We were unable to communicate with our dispatch on ACARS/HF/satcom. Air carrier Y assisted by having his dispatch contact our dispatch. Air carrier Y also advised us they were having trouble calling company due to a problem with air carrier Y communication in USA. Air carrier Y also assisted in ATC communication and WX information. Divert underway; accomplished all checklists. Diversion checklist; generator fail checklist. Right generator reset successfully. We did not attempt bus tie reset because we were satisfied with equipment we had and did not want to troubleshoot further. Made VMC approach; overweight landing at ZZZZ.

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Original NASA ASRS Text

Title: B767 FLT CREW REPORTS ELECTRICAL MALFUNCTIONS ENROUTE IN FOREIGN AIRSPACE AFTER BEING DISPATCHED WITH APU GEN INOP. RIGHT AC BUS REMAINS ISOLATED AFTER COMPLYING WITH QRH PROCEDURES AND FLT CREW ELECTS TO DECLARE AN EMERGENCY AND DIVERT.

Narrative: SCHEDULED TO FLY WITH AN APU GENERATOR INOP. PROBS WITH THE L GENERATOR CYCLING ON AND OFF DURING ENG START AND WHEN PULLING EXTERNAL PWR. ZZZZ MAINT COME ON BOARD; WE RESTARTED L MOTOR; ACFT X MECH CYCLED ELECTRIC PWR MANY TIMES BTWN EXTERNAL/GENERATOR #1/GENERATOR #2. ZZZZ MAINT; MYSELF; FO'S; MAINT AND DISPATCH ALL WERE CONVINCED THAT ALL WAS OK. RECEIVED NEW RELEASE; ADDED FUEL AND DEPARTED. ABOUT 3 HRS INTO FLT; R GENERATOR DROPPED OFF LINE. MANY EICAS MESSAGES. R GENERATOR; R BUS TIE ISOLATED. R ENG EEC OFF. DECLARED EMER; RECALLED FO TO COCKPIT. DIVERT TO ZZZZ. WE CHOSE ZZZZ OVER ZZZZ2 BECAUSE OF A LONGER RWY; LISTED AS PRIMARY DIVERSION ARPT IN FOM; NOTE IN FOM FOR ZZZZ2 DEEP DITCHES LOCATED AT BOTH ENDS OF RWY AND TALKING TO ACR Y WHO INFORMED US HE WAS OVER ZZZZ AND THE WX WAS PERFECT. ALSO THE FO HAD BEEN IN ZZZZ BEFORE. WE HAD SOME PROBS UNDERSTANDING ATC. USING MY EMER AUTH I INVITED A CURRENT ACR Z CAPT INTO THE COCKPIT TO HELP WITH COM AND HIS KNOWLEDGE OF ZZZZ. WE WERE UNABLE TO COMMUNICATE WITH OUR DISPATCH ON ACARS/HF/SATCOM. ACR Y ASSISTED BY HAVING HIS DISPATCH CONTACT OUR DISPATCH. ACR Y ALSO ADVISED US THEY WERE HAVING TROUBLE CALLING COMPANY DUE TO A PROB WITH ACR Y COM IN USA. ACR Y ALSO ASSISTED IN ATC COM AND WX INFO. DIVERT UNDERWAY; ACCOMPLISHED ALL CHKLISTS. DIVERSION CHKLIST; GENERATOR FAIL CHKLIST. R GENERATOR RESET SUCCESSFULLY. WE DID NOT ATTEMPT BUS TIE RESET BECAUSE WE WERE SATISFIED WITH EQUIP WE HAD AND DID NOT WANT TO TROUBLESHOOT FURTHER. MADE VMC APCH; OVERWT LNDG AT ZZZZ.

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.