1985 Ford F250 ignition problems

Did you replace the key cylinder? It's the key cylinder that usually has the spring-back. Can you start and drive the vehicle, anyway? If you just turn the key to on position, just where the dash lights come on, then jump the starter relay, the vehicle may start and run? If you try that, make sure the tranny is in park or neutral and parking brake is set. I realize that doesn't fix your problem, but, might get you out of a bind? I don't have much info on your model year.

@oilyspill: yes I replaced the key cylinder, but it is definetly not the part which has the spring back in it. I cant start the truck, however it is not the issue, it is at home and not my daily driver anyway. @Mike: thanks for the hint, I will start disasembling the steering column and see what I can find

The ignition switch at the base of the column is the part that has the spring in it. Sounds like you need a new ignition switch. (The elecrical switch, not the lock cylinder which is what you put the key into.)