Tim - I still am not understanding the issue.
Assuming the choke mechanism, and fast idle mechanism on the carb is not worn out, and is properly adjusted:
(1) Pushing the footfeed to the floor should allow the autochoke spring to almost close (the unloader circuit should cause the choke plate to be slightly (without knowing what carburetor by number, guessing 3/16 inch) open.
(2) Now releasing the footfeed should allow the choke plate to completely close assuming ambient at 65 degrees F. or less.
(3) When the choke plate completely closes, the fast idle link should go to the highest step on the fast idle cam. The throttle adjustment screw should now be maybe an 1/8 inch off the stop, and Hulk Hogan should not be able to close the throttle (well, maybe Hulk could
, but certainly not a throttle return spring (or 3) ).
(4) As the engine warms, hot air should allow the choke spring to relax, and the internal choke pull off to begin to open the choke plate, allowing the fast idle cam to rotate and the throttle return spring(s) to begin to close the throttle, and slow the idle.
(5) Having one's foot on the footfeed during the warm-up process will DEFEAT the action of the fast idle cam.
(6) The fast idle link, over time, will bend and thus need adjusting.
Where in central Missouri (in other words, how far from Eldon) are you located?
And speculating here, is your friend a Mopar enthusiast???
For some reason, known only to an unknown ambulance chaser, many Mopar products in this time period actually used the throttle return spring to close the throttle. If you were to place a carburetor for a Mopar on your workbench unattached to anything, the throttle plate would normally be approximately 60 percent open!!!! Conversely, placing the Chevrolet carburetor on your workbench unattached to anything would show the throttle plate closed. In other words, if the throttle return spring on a Mopar were to break while the vehicle was being driven, the throttle would immediately go wide open. The first time it happens can require a change of clothing!
Just for the record, I have a single throttle return spring on my shop truck with the 450 HP 390 utilizing two Carter AFB 4-barrel carbs which run simultaneously.
Jon.
