Tuning key problem

[jroot]

What does it mean when your tuning a string up and all of a sudden the tuning key will no longer turn? My high E is doing this and it stops turning just flat of pitch. My D string is also getting funny where the pitch position seems to be right in between two rough spots in the turn. Is this something intonation could fix? I know my machine heads are really getting old it is an 82 custom. The heads are the ones that the tuning winder pops out from and I really like them and do not want to have to put new keys on, unless I absolutely have to.

My guitar has the factory kahler trem and I haven't found anyone locally that can set this thing up correctly. That being said this tuning key problem started about a month ago. Same string guage as always, etc. I can use the fine tuning screws on the trem to get the E string to pitch for now but I can't help but feel I am sitting on a timebomb. Please advise and thanks.

 

[Rosewood]

Gear stripped? tunning button lose on shaft? Take a close look while it's slipping. What kind of gears are these?

 

[jroot]

I wish I knew and could explain the anatomy of the tuning head a little better. Mine are Gibson gold plated from 82. They look like the new modern style but they have a string winder that pops out of each tuning key. With no string on I can turn the key round and round forever. I also noticed the white washer between the key and part the key is hooked to is worn on a couple of them.
How would I know if I have a stripped gear?
Sorry for all the newb stuff here I just play em haven't had to fix them till now.

 

[Rosewood]

Look under the string winder and see if there is a small screw, make sure it has some tension on it, should be tight enough to feel a little snug, don't over tighten though. Check the height of the post that the strings attach to and see if the one slipping is shorter than the others, if so it's possible that the gears are not fully ingaged. Report back.

 

[mc5nrg]

Those "Crank" tuners were made by Schaller.

 

[jroot]

Thanks so much to everyone trying to help. Kinda feel stupid here, Inside the tuning key once you flip out the winder is a screw. It was loose on the offending tuners. All is well now. I was never able to track down nos or used Gibon/Schaller tuners. However I did finally find a guy on the bay that makes generic look a likes with the winders. I may grab a set just incase the day does come. Peace out