AN MLG AIR CARRIER CREW HAD A PROBLEM WITH ITS FUEL INDICATING SYS WHILE ON THE GND. THE FUEL SYS WORKED PROPERLY WHILE IN THE AIR.

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APPROX 45 MINS PRIOR TO DEP FROM BUR; THE FUELER NOTIFIED ME THAT THE FUEL AUTOMATICALLY SHUT OFF TO THE WINGS EARLIER THAN EXPECTED. WE VERIFIED THAT BOTH THE WING AND THE COCKPIT DIGITAL FUEL GAUGES READ THE SAME. THE FOLLOWING READING WAS OBSERVED: L: 8800; R:8950; CTR: 4850. DURING THE REMAINDER OF TIME PRIOR TO PUSHBACK; THE FO AND I OBSERVED THAT THE FUEL GAUGE READINGS WERE CHANGING. THE FOLLOWING READING WAS OBSERVED AT PUSHBACK: L: 9050; R: 9500; CTR: 3800. ALL PHASES OF FLT WERE COMPLETED THROUGH LEVEL-OFF AND THE FOLLOWING READING WAS OBSERVED AFTER WHICH I ACCOMPLISHED THE FUEL BALANCING PROC: L: 8800; R: 9400; CTR: 0000. NO FURTHER ACTION WAS NECESSARY AND AN UNEVENTFUL FLT WAS COMPLETED. CONCERN IN RETROSPECT: POSSIBLE GAUGE MALFUNCTION OR LEAKAGE FROM THE CTR TANK TO THE R TANK. BACKGND: THIS FLT SERIES WAS BUILT WITH A 3:30 LAYOVER BTWN AA00 LCL AND CC30 LCL AT BUR. EARLIER IN THE WK THE FUELER DESCRIBED TO ME IN CASUAL CONVERSATION A SIMILAR PREMATURE REFUELING SHUTOFF ON A DIFFERENT ACFT WITH THE SAME LAYOVER TIME. THERE WAS SOME DISCUSSION ABOUT THE POSSIBILITY OF HEAT EXPANSION IN THE WINGS. THEN; WHEN THE EVENT DESCRIBED ABOVE HAPPENED TO ME; THE SAME POSSIBILITIES WERE SUGGESTED AGAIN. SINCE THE FUEL WAS IN BAL; I SIMPLY APPLIED THE RESTRICTIONS CONCERNING LESS-THAN-FULL WING TANKS AND DEPARTED. I FELT THAT THIS WAS PREFERABLE TO TRYING TO MANUALLY TOP-OFF THE TANKS AND RISKING A FUEL SPILLAGE BECAUSE 'MANUAL' IS AN UNPROTECTED MODE. DISCUSSION: SINCE THERE WAS SOME CONCERN ABOUT WHETHER THE INCREASING OUTSIDE AIR TEMP COULD AFFECT THE FUEL READING (AND THEREFORE THE FUEL AUTO-SHUTOFF CAPABILITY); I WATCHED TO SEE IF THE GAUGES MIGHT 'SETTLE DOWN.' AS DESCRIBED; THEY DID MOVE. IN FACT; SINCE THE R GAUGE READ ITS MAX; I FELT REASSURED THAT THE TANK REALLY WAS FULL AND THAT THE GAUGE WAS JUST 'CATCHING UP.' AT PUSHBACK; THE FUEL WAS STILL WITHIN LATERAL LIMITS; SO I ELECTED TO DEPART AND FINE TUNE THE BAL ENRTE. NO ADVERSE FLT CHARACTERISTICS WERE EVER ENCOUNTERED. UPON ARR AT SEA (THE NEXT AND FINAL STOP); THE READINGS WERE ENTERED IN THE LOGBOOK FOR SEA MAINT TO CONSIDER. HUMAN PERFORMANCE CONSIDERATIONS: AT THIS WRITING; I DO NOT KNOW WHAT OUR MAINT PEOPLE FOUND OR WHETHER THERE WAS A REAL PROBLEM AT ALL. HOWEVER; IF I HAD THE SAME SITUATION AGAIN; I WOULD HAVE CALLED FOR THEIR OPINION PRIOR TO DEP (JUST TO BE SURE).