' Farm Fixes '
They were almost always " hurry up kiss me quick " typ repairs because the hay was lying in the field etc.....
IIRC , those Hollys had flooding issues , I'd double check the tune up complete , valve gaps , points to .016 / 33? dwell then timing to ball on pointer before touching the carby again ~ linkage disconnected it should be possible to make it start & idle , if too fast , then once warmed up you can adjust it to a decent 700 RPM (or less) idle speed , then see if it revs O.K. when you goose it , then begin fiddling with the various linkages & throttle rods as 253 was different than 216 was and even then , GM made many different bits over the decades , cast iron bell cranks , stamped sheet metal ones , on and on .
First and foremost is the bell crank and pivot pin in the side of the cylinder block ~ if the pivot pin has grooves , you'll have to either weld it up then hand file perfectly smooth again or over size the hole in the bell crank and cut a bit of thin wall pipe to suit as a bushing .
The 90? ends tend to be badly worn , again it's best to find good ones (I occasionally see PILES of brandy new rods @ PO-Mona cheaply) , I've had very good luck over the years using " Throttle Rod Clips " (Misnomer : Jesus Clips" to hold the throttle rod's into the joints , or , if your stuck on using those tiny cotter pins , find a supply of good quality flat washers with the *prefect* size hole in them and use two on each 90? connection ~ one on each side of the arm plus more as shims if necessary . if you really like to be clever you can weld a flat washer exactly and perfectly into place at the inner of the 90? bend and it'll hold the rod in the proper position .
The main things are two fold :
# 1 : carby easily starts the engine , idles fine and revs it smoothly when you open the throttle by hand , NO SNAPPING THE THROTTLE WHEN TESTING as it doesn't work thata way when you're driving , the long intake manifold takes a moment to flow the fuel/air mix .
# 2 : set up the linkages so they're smooth and easy to operate by hand ~ if you need a strong return spring , it's wrong and WILL give you grief . egg shaped holes in the arms will bind . welding and drilling is pretty easy but I mean WELDING , not brazing nor soldering ! best is gas welding .if it has brass color on it , it's far too soft and will rapidly wear and screw up again .
# 3 : the return spring MUST be weak and have as many coils in it as you can find ~ the more coils , the better it'll work ~ most places try to sell you a too stiff , to short the coil pack spring , this causes not only binding and high idle but also rapid wear of all those throttle linkages you spent so much time getting " Just So " .
I typically find the very best throttle linkage parts & springs , in junk boxes and on the worst looking junkers you've ever seen .
I might have some linkage bits left over you're welcome to as I'm deeply in debt to you for Cactus .
I hope this was helpful .