I have a 2.0 litre CU engine with some Solex Brosal carbs (Brazilian) H32/34 PDSI.2 (I think that is right) They were fitted by the PO and the van runs OK with them, they have been set up on a rolling road a couple of years ago.
I have just had the MOT done and the MOT man said it was running rich on tick over, in previous years a different MOT man said it was running lean at tick over (i assume this is correct as that is the whole idea of the twin vac distributor to get the emissions down)
I thought I would have a look to make sure the chokes were working correctly, both are but as I opened the throttle looking down the carb bore it is possible to see the inner venturi in one carb lifting by approx 2-3mm, looking at the other side the venturi is fixed.

If I rest my finger on the top of the venturi that move it feels that it is directly linked to the throttle opening.


Should it move or should it be fixed???
Thanks
Pete