Classic/Antique Car Repair: Car Floods, 1959 ford fairlane, power valve

Question
My first and only car is a 1959 Ford Fairlane with a 223 6cyl engine, manual choke!  The car starts up perfectly when the engine is cold.  However, if I have been driving the car, then turn it off and let it sit from anywhere between 5 minutes to 1.5 hours, it will flood if I try to start it up again.  Each time, I have to hold the gas pedal to the floor and let it crank for 5 seconds before the engine resarts.  If the car has sat less than 5 minutes before resarting, i do not have to touch the gas and there is no problem.  Likewise, if the car has sat more than 1.5 hours, I just give it a bit of choke, and it starts up promptly.  What could be wrong???    

I really appreciate people like you sharing their expertise with others who are interested in learning.

Alex

Answer
There is a gadget in the carburetor that is called a power valve. When the diaphragm in the valve gets a hole in it the condition that you describe, flooding" can take place. A sinking float will also cause the same problem. Looks like it is time to get the carburetor off and to a good rebuilder.
Brad