Hugo,

I agree with Mark - most likey weak mixture when off idle due to air leaks. Having done all the checks you have done, i would head for the inlet manifold and check all the take offs (servo and advance/retard)and the plugs of unused ports for leaks. Don't overlook the push in plugs on the ends of the manifold too.

Happy Hunting,

Dave

Thanks all, for your advice. It is great to be a member of the "club"
I took the vacuum advance tube of thinking the mechanism might be stuck ( the car has not been run properly for many years) so I applied some sucktion, which changed the running of the engine and now she seems to run OK. I will see, she is officially on the road from tomorrow, so I will take her for a run.
Thank for your help.
A great team

Hugo