My '86 F250/ 351W has a Holley 4160. Its not a daily driver, so every time I take her out after sitting, the truck will start after a couple pumps of the pedal, stall, start again, stall again, etc. In the winter it takes usually 4 iterations, in the summer 2 to 3.
I've adjusted the choke itself and the same problem persists. I asked this question before, and it led me to adjusting the choke pulloff, rather than just the choke housing. Electric choke btw.
Also, is there a quicker way to verify this is indeed my problem (thinking like limiting the choke pulloff with finger or coathanger if one man operation)? When the truck stalls, its about 3-5secs into firing, so an overly rich condition should only be present on that order of time. By my eye, when the choke does pulloff, it's probably wider than 1/4" but less than 1/2" - is that about right?
Over 1/4" sounds wide to me, but there should be a chart somewhere that tells you what it should be for your specific model. Since you mentioned the paper clip, I am going to assume you have the integral choke model.
It should be simple enough to test the operation. All you are doing with the paper clip is manually actuating the choke pull-off system by moving the piston. The piston normally works on vacuum. If you get the piston moving with the paper clip, then you can see how the whole system works by moving it back and forth, and it will become clear what to bend.