Technical Hard to start when warm ‘63 impala

Hey guys got a ‘63 impala v8 327 with stock Carter 4bbl carb. It fires right up when cold but when it sits 15 min or longer it almost doesn’t fire up. I gotta keep giving it gas once just to fire it up. It starts fine if I go to the store real quick under 15 min, if it’s 16 or longer , it’s hard to start it. Have to wait for the engine to be cold to fire up again.
Any ideas on remedying this problem?
Thanks

 

Don't pump the pedal.
If the fuel has percolated it may have boiled out and effectively flooded the engine.
When it's hard to start, and not from slow cranking, floor the pedal and hold it at WOT while cranking. Don't pump.
What happens?

 

First off make sure the choke is fully opened when the engine is at operating temperature.

If the engine is hard to start hot, it may be due to flooding which creates an over-rich fuel condition. Do not pump the accelerator when trying to restart. This will make things worse by making the fuel mixture even richer.

If the problem is due to flooding press the accelerator to the floor once and hold it there. Crank the engine for maybe 5 seconds then release the key while still holding the throttle wide open. Keep your foot to the floor and wait 5 or 10 seconds and then try cranking it again. You may have to go thru this cycle a few times keeping the throttle open. When the engine starts, then take your foot off the throttle.

Consider having the carb rebuilt and make all the needed adjustments by the book.

 

Good suggestions so far, here 's another.
When young, ( carb days ) my task was "bring in so and so's car".
Jump in the car touch nothing but the key. Crank 10, 15 seconds, if not dead cold,, badabing,
it's running. If not then once to the floor, off it again, and crank.
Unless it's cold and dead cold, it gonna run.
Years after I found, on road service, that an engine that was not responding and had been over pumped, a sure fire rescue was with a second party cranking, I'd introduce a live flame.
Not always safe but if the manifold is overloaded A good burp and a vroom.
Surely, not your conditon but the thing to watch out for is a leaky carb causing a heartbreak emergency.
Yes I understand that you seek repair advice.
This is just a way to control the day, and get you home.
Everything thatClayMart says with emphasis on the last line

 

Not going to argue, but at least try:

https://www.thecarburetorshop.com/Troubleshooting.htm#Hardstarthot

It costs nothing other than forgetting some of what you have done for decades, and it works!

Jon

 

My Chrysler benefited from an insulated gasket. Still not as good as when cold but better

 

This works on all of my old cars.

 

It just cranks up to 5 sec no start.

 

This is where the auto choke and choke valve ? are currently at.

 

I don't think that tells us anything. Is that with the engine cold? What happens to the choke when you touch the pedal and/or crank it?

 

Yeah that’s it cold. I don’t know anything about these carbs. So when I start it cold or hot, I’d my foot supposed to be on the gas but not pumping it? Once it starts then let it off?