What was found
AIRCRAFT WAS GROUNDED: MIA-GRU, FUEL DISAGREE EICAS 9.1LBS DIFF TOTALIZER VS CALCULATED. FLIGHT AIR RETURNED TO MIA ACCOUNT A DISCREPANCY BETWEEN THE CALCULATED FUEL QUANTITY AND THE FUEL TOTALIZER QUANTITY. N7LC WAS DISPLAYING A FUEL DISAGREE AND THE FUEL TOTALIZER WAS DISPLAYING A QUANTITY THAT WAS APPROXIMATELY 8000LBS LESS THAN THE CALCULATED FUEL QTY. SINCE THE DISCREPANCY WAS INCREASING WITH TIME THE CREW DECIDED TO RETURN TO MIA. EMERGENCY WAS DECLARED. ***SUPPLEMENTAL ACTION SECT. 4 AND 5: REMOVED & REPLACED L/H ENG FUEL PUMP IAW AMM 73-11-01 REMOVED & REPLACED L/H ENG HMU (P/N UNI0044, S/N WYGF4825) IAW AMM 73-21-14***(CLOSED)