A CO ALARM WAS NOTICED AT THE 2 EAST MAINS TAIL PIECE AND THE SECTION FOREMAN WAS NOTIFIED. HE FOUND FLAMES COMING FROM AN INTERNAL BEARING ON THE SECTION TAIL ROLLER. HE USED A 1/2"" HOSE AND EXTINGUISHED THE FLAME IN LESS THAN 3 MINUTES. THE FIRE NEVER LEFT THE BEARING HOUSING. THE HIGHEST CO READING WAS 12.5 PPM.