1911 Holley 4500 carburetor

[Jamie H]

I'm the proud new owner of a 1911 T touring that's equipped with the correct holley carb. I'm having difficulty getting it to start when cold. I've owned a few T's with later carbs that haven't had this issue.
My question is this - cast into the venturi is an weighted air valve that I assume opens at higher rpm. Is there supposed to be a spring helping keep the valve closed during cranking? The car will start if it's towed and it starts and runs quite well when warm. When hand cranking cold the spark plugs are dry. I'm thinking that the air valve may be opening letting air in but or course no fuel. I've opened the mixture screw a number of turns but no change.
I've been looking everywhere, however, other than some pictures there isn't a lot of information on this particular carb that I can find.
Any and all input would be appreciated

[Scott_Conger]

You may very well have the fuel level too low in the bowl.

[Jamie H]

I thought that as well, however, I've adjusted the float height so its just on the verge of flooding with no change. I had my neighbor put his hand on the carb inlet while I gave it a couple of pulls and he said that there was virtually no vacuum produced. Tried it again with the carb off and said there was lots of vacuum

[rickd]

Maybe its not the carb. You say it runs well when warmed up; maybe leaking manifolds downstream of the carb. Is your ignition system in good shape? The old adage, 90% of carburetor problems are electrical.