Carter YF at full throttle opening in resting position?

[Curt C]

I am in the process of getting a 1953 GMC half ton running again. The Zenith 228 carb is long gone. I talk to the folk at Carb Exchange and they said a Carter YF will work no problem. They sent me one and I have been looking at it. At rest the carburetor is fully open. It appears that the accelerator squirter arm is holding it in that position. You can actuate the throttle plate no problem but the spring on the accelerator pump arm forces it to rest completely open. Is that correct? Am I missing a return spring of sort? I have never seen a carb rest at full open.