See Figures 1, 2, 3 and 4
The Model 2100 and 2150 2-barrel carburetors have an air horn assembly that covers the main body and houses the choke plate and the internal fuel bowl vents. The throttle plate, accelerator pump assembly, power valve assembly, and fuel bowl are contained in the main body. The automatic choke is also attached to the main body. Each bore contains a main and booster venturi, a main fuel discharge, an accelerating pump discharge, an idle fuel discharge, and a throttle plate. They are used on V8 engines.
ADJUSTMENT - Float Level
The dry float level measurement is a preliminary check and must be followed by a wet float level measurement with the carburetor mounted on the engine.
- With the air horn removed and the fuel inlet needle seated lightly, gently raise the float and measure the distance between the main body gasket surface (gasket removed) and the top of the float.
- If necessary, bend the float tab to obtain the correct level.
See Figure 5
- Remove the screws that hold the air horn to the main body and break the seal between the air horn and main body. Leave the air horn and gasket loosely in place on top of the main body.
- Start the engine and allow it to idle for at least 3 minutes.
- After the engine has idled long enough to stabilize the fuel level, remove the air horn assembly.
- With the engine idling, use a T-scale to measure the distance surface to the surface of the fuel. The scale must be held at least 1 / 4 in. (6mm) away from any vertical surface to ensure proper measurement.
- If any adjustment is required, stop the engine to avoid a fire from fuel spraying on the engine.
- Bend the float tab upward to raise the level and downward to lower the level.
- Each time the float level is changed, the air horn must be temporarily positioned and the engine started to stabilize the fuel level before again checking it.
Initial Choke Valve Clearance
See Figures 6, 7, 8 and 9
- Remove the choke shield.
- Loosen the choke cover screws. Rotate the cover 1 / 4 turn counterclockwise.
- Disconnect the choke heat inlet tube. Align the fast idle speed adjusting screw with the indexed (second) step of the fast idle cam.
- Start the engine without moving the accelerator linkage.
- Turn the fast idle cam lever adjusting screw out 3 full turns. Measure the clearance between the lower edge of the choke valve and the air horn wall.
- Adjust by grasping the modulator arm with a pair of pliers and twisting with a second pair of pliers. Twist to the front to increase the clearance and toward the rear to decrease the clearance.
- Stop the engine and connect the heat tube. Turn the fast idle cam lever in 3 full turns.
- Don't reset the choke cover until the fast idle cam linkage adjustment is done.
Fast Idle Cam
See Figure 10
- Push down on the fast idle cam lever until the fast idle screw is in contact with the second step of the fast idle cam and against the shoulder of the high step.
- The specified clearance should be present between the lower edge of the choke valve and the air horn wall.
- The adjustment is made by turning the fast idle cam lever screw.
- The choke cover may now be adjusted.
Choke Unloader (Dechoke)
See Figures 11 and 12
- With the throttle held completely open, move the choke valve to the closed position.
- Measure the distance between the lower edge of the choke valve and the air horn wall.
- Adjust by bending the tang on the fast idle speed lever which is located on the throttle shaft.
Final unloader adjustment must be performed on the car and the throttle should be opened by using the accelerator pedal of the car. This is to be sure that full throttle operation is achieved.
See Figures 13 and 14
The accelerator pump operating rod must be positioned in the proper holes of the accelerator pump lever and the throttle overtravel lever to assure contact pump travel. If adjusting is required, additional holes are provided in the throttle overtravel lever.
Adjust the fast idle setting with the engine at operating temperature. The fast idle screw should be resting against the second step of the fast idle cam. Adjust by turning the fast idle screw.