I am helping my dad restore a 24l DB touring. The car is almost completely restored, but we have a question about the carb and choke.

We notice the engine only wants run with the choke partly closed with the choke knob partly pulled out. I was looking today and don't see an adjustment on the carb for fuel/air mix. Is the choke some how used for fuel air mix adjustments? We didn't see any screws etc to adjust the fuel air mix. There is a screw stop for the choke and one for the throttle. I also doubt the screw stop is adjusted correctly.

Thanks for any help,

Larry