I've found a 5mm ball bearing rattling about in the nooks and crannies of the carb before, it made no difference to how the car ran and I couldn't find anywhere that looked like a home for it.

Heh heh, you missed the many hours of polishing before i got the carb ready for its photo shoot!

Seriously credit to Neil the van is clean as a whistle, apart from all the cow muck it now picks up on these yorkshire lanes...

That amuses me. i thought i was just a messy bugger.

I can almost hear Neil crying.

Thats priceless, cos it so true.

Just to prove I'm not going mad - here are the carbs from Dudley, the 86 D***y and the Beige Beast...Neither have the piece of aforementioned metal.

have you or the previous owner ever lost a detent ball from the gearbox top....eh?
sean

nelsthebass, i agree not all had them, as i say one of the loose carbs in the shed didnt have it, but to be pedantic. the second pic of yours does have that part(although it is a different shape), you can just see it at the bottom of the solex ali ID tag

its the second butterfly stop screw

there were many tiny variation on the solex carb over the years/markets

the original problem may be because as the linkages on the carb become worn and the whole thing can go "over centre" and stick

carefull ajustment of the throttle cable as well as moving the return spring from the outboard location on to the throttle cable pin helps

I'll throw my penny's worth in....

My car has had a problem over the years, where the throttle jams open. It tends to happen after a long motorway drive-so flat out for 100+miles, and I do find that a liberal squirt of WD40 cures it. I've never bothered to look into the cause, it's not been worth it for me, as it's not something that occurs very often and when it does, it's not been too scary