New Qjet carb - Starts, then dies

[1968_K20_4x4]

Hello Everyone!

I purchased a rebuilt (Autoline from Napa) Quadrajetet carb for my 1972 Chevy K20. I installed it with an aftermarket electric choke kit from Quadrajetparts.com, however the truck does not start like it should. I gently press the pedal to the floor once to set the choke, it will fire up, run for 2 seconds, then die. I wait a few seconds, press the pedal to the floor again and re-start. The truck will then start and run fine.

I have tried a few tricks- half a pump then crank to start, two pumps then crank to start, adjusted the choke rich/lean, adjust idle set screw, hot or very cold day - the truck starts the same way every time. No matter what I do the truck starts then dies after a couple seconds.

The choke pull-off appears to be working properly as it pulls the choke blade open slightly right away.

When its warmed up the truck always starts right away and runs fine with no issues, although it does seem very easy to flood when warm and once flooded will not start even if you hold the pedal to the floor.

I am wondering if it is a fuel delivery problem... I am running a lower pressure fuel pump (4-6psi) with an inline fuel filter as well as the stock filter inside the carb... Maybe not enough fuel on start up???

I have not adjusted the Choke Pull-off or the high-idle.

I am new to carb adjustment/tuning so any insights as to what is going on here or ideas of what to check/adjust next would be greatly appreciated.

I have attached a couple crappy pics - I can take better ones of the carb set up later but for now this is all I have (BTW my motor is a marine 307 if youre wondering..lol)