Anybody know the "exact" choke pull off clearance for a 73 302 2100 carb? I can't find the exact answer it seems that everybody just takes a guess to get it right. I have a rebuild sheet from a 2100 I rebuilt a couple years ago and it does not tell. Thanks.

 

I have a rebuild sheet that shows it as 9/64" for a '72 with a 302, but nothing for a '73. A few cars with a 302 have it listed as 11/64", and some others as 5/32" (10/64"). I'd leave it at 5/32" and see how it does. That should be close enough, unless someone happens to chime in with something closer. I realize that's not the "exact" specification you're looking for, but unless someone can find it in a book, that's the best anyone can do. I don't know why several clearances are omitted; I've had this problem before too. You would be surprised at how many people don't even bother to look.

 

There is no EXACT choke pulloff clearance after 37 years. The motor is old, the carb is old and the air is different. It's what works. If the choke is adjusted right and everything else is OK then you adjust other stuff to make the truck run right. Everything seems to point to 7/16 for the float. Mine looked close to that so I left it. All fuel is drawn from the bottom of the carb. So if it is less then but not too low, the engine will still draw fuel. Remember the pump is still filling that bowl. You have got to start with something. When I rebuilt the carb the choke was at 1 lean. I left it there. I also didn't touch the high speed idle, the choke pull back or the idle setting. Mixtures were about 3.5 from all the way in. Started the motor in the morning. It ran OK. The truck stalled. When I started it again it idled too high and sputtered. Driving it around I noticed that whenever I stopped for a half an hour that the choke was coming on. More on that later. Still sputtered. Idled too high also. Later that day I moved the choke to a leaner setting. One more notch lean, which is clockwise. Hope you have an old style watch. I turned the high idle down 1/4 turn. Turned out the mixture 1/4 turn and lowered the idle 1/4 turn. You now have to wait till the next day till all is cooled off. Fire it up again. Truck still stalls when I first start it. Turn the pull back in 1/4 turn and wait till the next day. Idling too fast around town, turn the idle down next time you stop for coffee. I kept changing the settings until I find what is right. I have slowly got it. Not perfect but pretty well for a 77 - 400 CI. Still got some tuning to do.

Jim
77 F150 - 400 CI
Man this thing burns gas, I gotta adjust the carb!

 

Maybe you misread the post or I didn't explain enough. The engine runs great, I get 22 miles a gallon on highway. The engine has never been rebuilt and has 57,000 miles on it and I bought the carb completely refurbished from Pony Carburetors.

The choke works great also. My problem is I cant get the choke pull off just right for my liking. I either get it to where it doesnt open enough and the engine black smokes while warming up, I go back and adjust it some more then I get it to where It wants to start and die the first couple times I start it. Thats the whole reason I want to know the exact measurement Ford had it when it was new. I have the curb idle set at 600rpm and I set the high idle at 1200rpm.

 

It seems that everything I find keeps leaning towards 5/32 like FMC said. I am going to set it at that and see how it reacts. I know I have to check and re-adjust fast idle index after adjusting choke pull off adjustment.

 

I apologize. Did you ever get the pull back working right? I would like to give you my high idle rpm number but I threw out my timming gun and rpm tester when I thought I would never own another carb truck. So much for that.
Jim
77 - F150 - 400 CI