All a bit odd this John as it would appear the clutch is not disengaging [no adjustment] yet smell of burning clutch would indicate its slipping. I think you are going to have to bite the bullet

What does it do with the cable disconnected at the gearbox end? Like that, obviously, the clutch should be properly engaged and the realease arm should sit in the correct place. If it isn't or it doesn't I predict you'll be pulling the engine out......

Engine is now out. The clutch arm was slightly bent, but I suspect that was a result of me artificially lengthening the cable outer in an attempt to make the clutch work. I think the problem lies in the clutch itself, since the release bearing (which is the right one for the clutch, by the way) is moving as soon as the pedal is depressed, and it seems to be moving along the input shaft about the right distance. But it ain't getting as far as the clutch springs. I have some photos which I'll upload after I've had some sleep.
Next step is to have a good look at the clutch unit, if it's not raining when I get up, then I'm probably going to have to bite the bullet and buy a nice new clutch kit from Uncle Roy. I honestly can't think what else it could be, now.

Been having a play with the Ami (or "the fucking Ami" as it shall henceforth be known) today and I'm still baffled.
The clutch arm isn't bent, although that didn't stop me spending an entertaining half hour dismantling the brakes in order to try and change it for one that was definitely ok when last used. (I still can't work out how to do that, incidentally: can you change the clutch arm without removing the brake drum backing plates?)
The clutch appears to be ok.
The release bearing is in good order and correct for the clutch.
When the clutch pedal is pushed to the floor, the release arm is back against the bellhousing.
I'm lost now, completely run out of ideas. Although I suspect I will feel like a complete idiot when it's eventually solved, as I'm sure it's something blindingly obvious that I've overlooked.

Clutch


Clutch arm, slighty bent ...


... and after straightening ...


... and compared with potential replacement arm. They look pretty similar to me.

The clutch is indeed engaged in these circumstances. Release arm sits with the end poking out over the gap between the bellhousing and the engine, just as it does on my spare gearbox.

RT,
looking at your photographs, that pressure plate is past its best.
At the inner end of the 3 operating levers, the sections which contact the release bearing would have been rounded when new and if they're flattened off like those are, you'll have problems disengaging the clutch.

I've just been back out to the shed and bolted an almost new pressure plate, plus new driven plate, onto a flywheel.
Placing a straightedge between the tops of the cups which the pressure springs bear against, it's 'about' 15mm to the top of the rounded surfaces of the levers.

In the second photograph, when the forks at the top end of the clutch release arm have spread out like those have done, it's usually a sign that they've been overloaded, usually a direct result of trying to re-use a worn-out pressure plate.
It might be worth cleaning that off and having a look for signs of cracking at the narrow part of the fingers.

Ditto for the actual contact surface on the fingers, which would have been rounded when new.
On the release arm which had rust showing, those parts are flattened quite badly.
Too much wear there and the arm runs out of travel, with the lower part contacting the gearbox casing.
Tightening the cable to try and obtain more travel can bend of break the arm, or even pull the cable through its attachment point.

Not good news, so apologies...

ken

( Almost forgot, when the fingers are splayed out, they can slip off the contact surface on the back of the release bearing, so need to be bent back into shape, carefully. )

I dont know if it makes a difference, but that flywheel is off a drum brake dyane bitsa shitheap I had, I assume its the correct one for a drum brake dyane. I used it because the measurement between the mating face of the original M4 crank and the friction surface was the same as the flywheel thats in there, but completely different to the 2CV ones I had, most of which were the lighter D*lly type.. I don't know what your clutch and release bearing are for or if it makes the slightest difference at all, but thought I'd throw that in.

No, that's actually excellent news, especially your first sentence. It means that with the simple flexing of my credit card and five minutes on Uncle Roy's website, I can sort the whole thing out. Just off to order a new clutch and release arm ...