Hi all,
Just an update. I finally decided to bite the bullet an open the Yashica D.
I followed the instructions from the link earlier in the thread and it went mostly to plan but I did make a couple of small mistakes. I took the screw out of the speed regulator top plate when you are not supposed to and this caused a lever to become disengaged with a slot on the main quarter cog (for want of a better description) which I did not spot. More on this later.
I found that for some reason the part of the mechanism that controls the firing of the shutter was on the REAR of the little lever that it pushes and not the front so in that configuration it could never fire. This confused me as to why that was there as I HAD fired it previously before it jammed up. I think, looking back I may have turned the speed control AFTER cocking the shutter in my panic after the shutter jammed originally. Not too sure, but I can't see any other explanation. It was quite easy to reset to the correct location though which I did.
I then dismantled everything down to the shutter blades and shims and I was quite pleased to find that they were gummed together with some unknown substance.
My original plan was to clean these with a Q-tip and some iso-alcohol but I did not have any or any lighter fluid so I used automotive brake/carb cleaner and it cleaned them beautifully without any marks and got rid of all the weird substance which was yellow on the Q-tip so I'm guessing it was some sort of oil/grease originally. I managed to reassemble the blades and shims on the second attempt. On the first attempt the blades fell out into the middle of the assembly!
I also cleaned the lenses and blew out any dust while I had them apart. I managed to get the assembly back together but realized that the four retaining screws are all different and it does actually tell you to mark them in the article (must have missed it), but you can soon see which goes where by inspection.
I also had an errant flash contact spring on the table but thanks to the diagram I put it back in place.
So, with the shutter assembly back together I tested it and it fired! shutter snapped sharply open and then closed again. Brilliant! So, on with the speed control ring and fixing ring. It seemed to fire at top speed (1/500) but it did this no matter what I set the speed to! dismantle again...
I found the culprit which was the disengaged quarter cog and lever on the speed controller, so I carefully took the screw out and lifted the top plate just enough to re-engage the mechanism, then reassemble again and test. This time the speeds seemed to work ok.
Reassemble the camera, solder the flash wire on and test. She seems to fire on all speeds now smoothly and with nice clean lenses too!
It took me five hours in total (including mistakes and a few cups of tea!). Really pleased now and I can't wait to load up some film and go shooting.
The only issue now is that the original front leather effect covering has gone brittle and broke off in lumps, so I now have a very scruffy front which is ok, but I would like to replace it if possible. Does anyone know of a source for this material that I can cut to shape and glue on?
Thank you for reading and I hope I have not bored you too much.
p.s. apologies for the terrible cell-phone pictures!