Major issues with Cabby

Really struggling with my Cabby.

For whatever reason its stopped idling. Last week it would happily sit at 700rpm but now the minute you push the choke in and it drops below 1300 it just dies. I've spent hours checking fuel filters, looking for vacuum leaks and I just cant figure it out.

Its a weber 32/34 and i had it stripped down and cleaned out by a mechanic back in may. He said it was as clean as a whistle therefore I don't think its that. Anyone got any Ideas or in the Teesside/Darlington area that wouldn't mind taking a look?

cheers Richard

That does sound like a vacuume leak to me. Although, do you have a fuel filter on the car? If not, maybe a bran flake ( bit of rust or crap ) has made its way to the carb?

Have you checked the condition of the fuel filler neck?  

Ive removed the carb to try and diagnose the problem. It seems that there is a small tear in the gasket that sits in the middle of the carb. The floats seem to be free moving and the jets are clear.

One thing i did notice was there was a brass screw that was sat on top of my exhaust manifold that i very clearly remember been connected to the front of the carb. I've since refitted and tightened it up. The screw can be seen in the image below, brass one. Does anyone have any ideas what its for? please bare in mind the image is sideways.

If your referring to the one on the right? that is the Idle screw and it should also have a spring  :wink:
Seems your running issues were a combination of both air leak i.e split in the carb flange and the idle screw missing.

The idle screw is present, I know that becuase I was trying to adjust it the other day, I was refering to the big shiney brass nut right in the middle of the picture. Thats what I found sat on top of the inlet manifold, god knows how its come undone.

Not a clue what it is for and never had one come out in my years of owning, using weber carb's