Quick Quadraject question - Internal Leak?

[Shugalou]

When I turn the idle adjust screws all the way in (to the right) I was expecting this would cause the truck to die but it didn't...I didn't notice any difference in idle. I did this after I adjusted the idle screw.

Wondering could this be an internal leak? Or stuck on the high idle/choke? I'm new to carbs and learning as I go. Most likely I will be rebuilding the carb just wondering what you experts have to say.

Thanks guys much appreciated!