Occasionally my 78 CJ7 won't do anything when you turn the key in the switch unless you "Fonzy" (bump the bottom with your palm) the steering column. It then cranks as normal. Any ideas?
Sounds like your switch may need to be adjusted as it's not in the correct position or it's just worn out.
At the base of the column look for the switch where the wires plug in. The switch will have elongated slots that you can adjust.
The correct procedure is to pull the plug or disconnect the battery, put the key in run, loosen the mounting screws and adjust the switch to be in the correct position. There should be detents.