If it is a Shimano FD than the number is on the inside of the inner cage. Without that, its hard to diagnose if its the derailleur or something else. My recommendation is to turn the rear of the FD out a little so it doesn't rub when in the large/small combo, then see if it works okay in other combinations. There is some wiggle room in setting up triples. Sheldon Brown gave some ideas why you might not want the outer cage perfectly parallel with the chainrings.