Model A & B
Ford Garage
NOS Zenith Carburetor
Shown below is an NOS Zenith Model B style carburetor made for the Model A.
Ford initially serviced the Model A directly with the same carburetor as used on the Model B (B-9510-A1), and then later with the Marvel Schebler 8-2843 (B-9510-A2), and lastly with the Tillotson Model XF (B-9510-A3).
The carburetor below is actually a Model 124 1/2F carburetor made and sold directly by Zenith for aftermarket replacement on the Model A Ford, not the Model B.
This type of carburetor was sold through independent auto parts stores and garages, not Ford authorized Ford dealers and parts distribution.
fordgarage.com
fordgarage.comThis particular Zenith Model 124 1/2F O-6989 carburetor does not have a Ford part number and is slightly different than the Ford production Model B carburetor.
This carburetor was specifically made for the Model A's gravity fuel system and smaller intake manifold size.
The Model 124 1/2F O-6989 venturi is a smaller diameter size number 20 compared to the larger internal diameter Model B size of number 22.
The Model 124 1/2F O-6989 float valve orifice is a larger number 54 compared to the smaller Model B size of number 44. This difference is due to the difference in fuel line pressure between a lower Model A gravity system and the higher Model B fuel pump system.
The Model 124 1/2F O-6989 main jet is a smaller number 18 instead of number 19, and the compensator jet is a smaller number 17 instead of a number 18. The Model B used the larger orifice size jets.
Special thanks to Rob Mills for the photos of his NOS carburetor.
Shown below are the Zenith parts book illustrations showing the two models, one for Model B (O-7021) and one especially for the Model A (O-6989).
These carburetors were both the 124-1/2F series.
It is not clear why they are labeled as 1" size, since Ford described them as 1-1/8" size, and the throttle bore actually measures 1-1/4".
More related information on Ford Garage:
- For more Model A & B related information, use the Site Search box at the top or bottom of this page.
- Model A & B Zenith Carburetor Jet Sizes & Flow Rates
- Model B & 46 Zenith Carburetor Parts Catalog Illustrations
- Model B & 46 Zenith Carburetor Assembly Drawings
- Model B & 46 Zenith Carburetor Float Details
- Model B & 46 Zenith Float Valve Orifice Details
- Model B & 46 Zenith Carburetor Power Jet Circuit
- Model B & 46 Zenith Carburetor Power Jet Tube
- Model B & 46 Zenith Carburetor Power Jet Tube Instructions
- Model B & 46 Zenith Carburetor Catalog Data
- Model B & 46 Zenith Carburetor Upper Casting Variations
Vince Falter
May 2005
