Ok, it looks like it was just a clogged chute. Thanks for your help.

Dave

I add this.
What about cleaning the doser chamber?
I ask it, because I feel difficult to move the handle,after 7 years of use.
Any suggestions?
Regards,
Theodore.

It's worthwhile to clean the doser chamber itself but the binding is more likely to be in the doser arm and return spring assembly. Unload the grinder, invert and remove the two small hex screws that hold the bottom plate of the doser assembly in place. You'll need a 3 mm hex/allen wrench to loosen them. Slide that assembly out and you'll find a center ratchet gear with a doser return spring that is - when it works correctly - designed to make the handle spring back automatically after each thwack.

If your issue is that it's hard to pull rather than just not springing back then it could be a need for some lubrication grease on the ratchet gear, repositioning of the spring or just a thorough cleaning. I'm inclined to think that it's somethign other than just coffee grounds impeding the handle action - I've cleaned a number of these that had once been in heavy commercial use and rarely found that to be an issue.

There's a thread here somewhere (or a link to one) that has excellent photographs of an entire doser chamber disassembly and reassembly. In the meantime.... here are some low res diagrams that may be helpful.

Is it safe to assume that the only difference between changing the Burrs and the instructions above for cleaning is taking out the screws pictured pulling off the burrs and putting the new ones on? (I can't imagine what else would make it more complicated but it seems wise to ask.) Also is it safe to assume that the Super Jolly instructions are essentially the same as the mini instructions?

And finally is there a difference between the upper and lower burr (perhaps it will be obvious once I open it up, but my hunch is that the answer is no)?

Yes, that is essentially how to change the burrs. The top and bottom burrs are the same.