Originally Posted by
Pars
I think there were some later Campy cranks that had the self extractors that one side was left hand (or maybe both?). From what I recall, these used 7mm allen keys.
I've never seen '70s/'80s crank bolts (Nuovo/Super Record) that were allen key. Normally these are 15mm hex.
My guess is that this^ or something like this, is what you're dealing with, might even be a non-Campy self-extractor installed on the Campy crank...so pics would help!
If my guess is correct you would turn the Allen-head bolt CLOCKWISE to effect the self-extraction.