Some of the Carter YF carbs (including most of the aftermarket ones for Chevrolet) have the spring loaded fuel valve. Most of the aftermarket kits did not offer this spring loaded valve because it is much more expensive than the solid valve. Someone in the past may have rebuild the carb with the cheaper solid valve, and readusted the float. Use the spring loaded one, it is far superior.

The float may be adjusted two ways:

(A) by changing the thickness of the gasket under the fuel valve seat.

(B) by bending the tang on the float

If possible, A is preferable to B.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
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