I know this is too obvious to be 'it' but you don't have the wheel cranked, do you? What I mean is, do you have a lot of stress on the locking mechanism? That is, have you tried gripping the wheel and turning it to make sure it is not just caught by "wheel tension"?

I am not wording this very well...................... but my sister is in the hospital and things look very, very bad. My mind is not right.