Most Carter AFBs use the wire mesh filter like #53 in this illustration.
This is the mesh filter used by most Carter AFB carburetors. One end is closed, this goes toward the inside of the carburetor (open end toward fuel line). You’ll need a fuel fitting gasket as well.
This image shows two common inlet fittings for the AFB. The one on the left will use the screen filter, the one on the right has a snub nose and will not use a strainer.
The AFB with the snub nosed fitting above would use a 30-57 mesh screen in the needle and seat as shown in this image.
Find AFB needle and seat assemblies here.
Some AFB carbs use a bronze (stone) filter as shown in the illustration here, #30. The closed end goes into the carb first, open end toward fuel line. Don’t forget the spring and gaskets.
NOTE: Even with the above filters installed, I still recommend and inline fuel filter to prevent debris from the gas tank and lines from entering the carburetor.
INSTALL TIP: If you have a leak at the fuel fitting, please do not use teflon tape. That will break down and flush through the carburetor over time, blocking the needle and seat assembly. You can use liquid teflon, just keep it to the outside of the fitting. If you are experiencing leaking, make sure you’re using the proper gaskets and the threads in the carb body are in good condition.