What was found
(CAN) DURING MAINT. IT WAS OBSERVED THAT FUEL WAS GETTING INTO THE CENTER TANK (CTR. TANK QUANTITY INCREASE OVER TIME) WHEN EVER THE BOOST PUMPS WERE SELECTED ON. INVESTIGATION BY MAINT. IDENTIFIED A CRACK ON TUBE CC670621042 LOCATED IN THE RT SIDE OF THE CENTER TANK. MAINTENANCE REPLACED THE DEFECTIVE TUBE SECTION. THIS CRACK WAS FOUND POST SB 670BA28008. THE SB IS CALLING FOR THE INSPECTION OF THE FWD END OF THE TUBE AND NOT THE AFT END OF THE TUBE WHERE THE CRACK WAS FOUND.