Note: Picture to be used for reference only. Carburetor models may vary.
Note: Please read all the WARNINGS below.
CAUTION: For reasons of customer safety, we do not recommend that the fuel level in your Stromberg carburetor is set ‘wet’, measuring the level of fuel in the bowl. We recommend setting the float level ‘dry’, as we do at the factory with excellent results.
a) Disconnect the accelerator pump rod (3) from the ball sockets at each end. Remove the choke lever fulcrum screw (1) and disconnect the choke valve tension spring (14) using the pliers. Remove the five airhorn screws (31) and their lock washers. Lift the airhorn (32) off, with the accelerator pump(10) attached, carefully pulling the accelerator pump leather through the airhorn gasket (20). Unscrew the float pin and remove from the bowl casting. Remove float.
b) Holding the new float at the hinge end, insert it into the float bowl and install the new float pin into the casting, capturing the float hinge. Tighten the float pin.
c) To achieve the correct fuel level when the carburetor is in use, simply adjust the float hinge to ensure that the float sits level in the bowl when the inlet valve is fully closed. By ‘level’, we mean that the top surface of the float should be parallel with the top edge of the casting (not at the same height) and not pointing up or down at either end. The simplest way to check this is to hold the carburetor upside down and eye the float through to check it is parallel with the edge of the casting. Adjustment is made by bending the float hinge which contacts the ball in the end of the Stromberg SJet (or the needle in the traditional needle valve). Holding the horizontal part of the hinge with the pliers to prevent bending the body of the float, move the vertical part of the hinge away from the float body to lower the fuel level and vice versa.
WARNING! Before any work is carried out, the carburetor should be dried of any fuel as gasoline and gasoline vapors are very flammable. Check for and remove any gasoline or other fluids and loose parts, especially before turning the carburetor upside down.
d) The Genuine Stromberg brass float is exact to the original Stromberg drawings, but with some aftermarket inlet needle valves (not ours) you sometimes need to adjust the hinge forward so much that the top horizontal part of the hinge can hit the inside wall of the casting (above the inlet valve) before it shuts the valve off, causing flooding. This is because some aftermarket inlet valves (again, not ours!) are too short inside the float bowl. The fix is to nip the end off the top tang with some side cutters so the float hinge shuts the valve off before hitting the casting wall. Alternatively, use a Genuine Stromberg S-jet inlet valve (9564K).
e) Replace the airhorn and other parts in reverse order, taking care not to wrinkle the accelerator pump leather washer or catch it on the slot in the accelerator pump well. Use a new airhorn gasket (20). Tighten the airhorn screws (31) to 5in./lbs. minimum.
f) Manually operate the throttle lever and choke mechanisms, checking for sticking, binding, ‘overcenter’ movement, or malfunction.
You’re done! If you think we’ve missed anything or we could improve on this Genuine Stromberg ‘How To’, please let us know. Email – firstname.lastname@example.org