Lens mount on Nikon F4

I have a Nikon F4. The autofocus drive mechanism would not stay out

after pushing in the lens release button. I took the lens mount off

of the camera (4 screws). Everything looked fine and I replaced back

on. After pushing the lens release in and out a lot of times it is

now working as it should. The camera had not been used in a while.

Everything appears to be working correctly. The autofocus focuses

like it should. My question is: By taking off the lens mount, does

anything get out of alignment? Does the autofocus have to be re-

aligned? I did not think about an alignment issue untill after I had

removed it.There are no adjustments that can be made to the mount.

Not that I have ever opened my F4, but many other cameras. I have never seen any shims anywhere making calibration possible so I'm sure the factories rely on well machined parts that can only be mounted the right way.