The original Ford / Zenith carburetor valve number found stamped on the valve is the orifice size as expressed in 0.05 mm increments. For example, a valve marked number '44' has an orifice diameter of (44)*(0.05) = 2.2 mm = 0.0866 inches.
Zenith made a whole series of carburetors based on the Model B designs and component sets for other manufacturers, and there are a variety of valves found which look similar but which are not the correct size for the Model B.
The table below shows the orifice sizes for various original Zenith valves encountered, as well as some replacement valves. Beware of using valves with too small opening sizes.
The correct size valve when used with a fuel pump is a '44', while the '54' is correct for gravity fed carburetors. Significantly different valve sizes may cause fuel delivery problems.
| B-9564 Float Valve | Number Size |
Orifice Diameter (inches) |
|---|---|---|
| Zenith - Standard Model B with fuel pump |
44 | 0.0866 |
| Zenith - other | 45 | 0.0886 |
| Zenith - For use on Model A with gravity feed |
54 | 0.1063 |
| Zenith - other | 55 | 0.1093 |
| Stipe - ball type | ~ | 0.0955 |