The pictures posted are too small for me to understand, but I posted factory Carter service procedures on my website years ago.

Here is the one for the YF:

https://www.thecarburetorshop.com/Service_Carter_YF.pdf


YF CARBURETOR

Back out throttle lever set screw to allow the throttle valve to seat in the bore of the carburetor. Press down hard on upper end of the diaphragm shaft. Press hard enough to compress the upper spring -until you can feel the diaphragm bottom in the casting. With throttle valve seated and diaphragm shaft held in this position the metering rod should be bottomed in the casting. A side to side movement of the carburetor should allow the upper end of the metering rod to slide freely back and forth over the metering rod pin.

Adjust by bending metering rod pin lip on the metering rod arm up or down.

The use of tool T109-212 will greatly facilitate making this adjustment"

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop