I am restoring my 1981 full sized Bronco and running into an issue with my ignition. It started with someone attempting to steal my Bronco and the key wouldn't turn. I replaced the key and cylinder and it worked fine for a while. I got a mechanic to look at it and he said the column needed to be replaced so we found a very good quality used column in excellent shape and he installed it. The key worked fine again for a while and stopped again. Now I live in Michigan where we are setting records for coldness and the colder it gets the less the ignition wants to work. We have lubed the cylinder with graphite and it works for a bit then stops. I don't know what else I can replace to fix this problem...

 

After my original ignition tumbler wore out I went through two more tumblers in one summer before I got rid of the theft disk inside the mechanism the tumbler goes into.

 

How do you remove that??

 

Its been awhile since I did this but after you remove the tumbler, the disk is held in by a snap ring wire, a pain to get out but with some patients and some oring picks you can dig it out the disk should come out easily, then reinstall the tumbler. the disk is an attempt to stop the use of a "screwdriver key"
let me know how you make out.

 

By the way, make sure your switch mechanism is moving freely before you reinstall the lock.