06-07-14, 08:25 AM
I am an on site engineer in hydraulics and occassionaly come across this issue. The best way out I have found is to get a torx bit that is a little larger than the hex, use a hammer to seat it securely. , the torx bit cuts its own profile into the cap screw and the combination of the tapping and the better fitting bit helps get it out. Never failed me yet. Even tried it on m16 cap screws just a larger scale.
Good luck
Good luck