Canon A1 - Stuck AE Mode Selector Dial?

Hi there, I just purchased a Canon A1 as an upgrade to my FT QL. The camera seems to function perfectly well, with the exception of the AE Mode Selector Dial, which allows you to switch between Av and Tv AE modes. At first I thought the dial was stuck on Tv, however I then realised that it can be turned between the two choices but it's very stuck and requires a great deal of force to turn. Given that it's sawtoothed metal, this is very painful and it takes a long time to get the right angle/grip for it to turn. Is there any way I can lubricate the dial to make it easier to turn?

The dial in question is this one:

 

Also, is there any way I can know that my light seals are working well aside from running a roll through the camera?

 

Thanks!

the camera is about 40 years old and anything can happen to it. It is mostly plastic and often has problems of sticky "anything". I guess it can be serviced but that would be inefficient money-wise. I used to buy a lot of used cameras, and for the AE-1 and A1, something is sticky often tells me it is not well kept and I would stay away from it.

Perhaps a small amount of lubricant will free it up. Or why not set the dial to the mode you normally use, and leave it there?

 

The light seals and mirror bumper invariably need replacing on cameras of that era, you can do it yourself. I've never found it necessary to remove the old sticky material from the grooves above and below the film door as is often advised. Just clean it off the edges of the door and make sure there are no bits of film etc in the grooves. I run silicone glue into the grooves with a tiny screwdriver or similar, it's easy to wipe away the excess with a rag soaked in lighter fluid. Then stretch and press the black knitting wool/yarn into the grooves, trim and tuck in the ends, wet the edges to prevent the door from sticking shut, and close the back to compress the wool into the grooves - it will be rather stiff to close at first. Open it after an hour or so to make sure it doesn't stick shut.

 

Its important to leave a gap to make sure the lever which resets the film counter isn't blocked - it's invariably to the top right hand side of the upper groove. The hinge seal and mirror bumper are replaced with sticky back black felt.