Those are my favorite diesel engines! They were GM's F series, which were produced between, I believe, 1939 and 1960. Very art deco. They kind of epitomized the spirit of progress and motion that typified the era. The two most common models were the F3 and F7. I suspect that is an F3 though the distinctions are subtle.
As a recovering rail geek, my friend, I'm forced to point out that those are E's, not F's.
E9 set I believe.