AUTOMATIC CHOKE ADJUSTMENT
- Disconnect the choke rod from the choke lever at the carburetor.
- While holding the choke valve shut, pull the choke rod up against the stop in the thermostat housing.
- Adjust the length of the choke rod so that the bottom edge of the choke rod is even with the top edge of the hole in the choke lever.
- Check the linkage for freedom of operation.
IDLE VENT ADJUSTMENT
See Figure 1
- Position the carburetor lever on the low step of the fast idle cam.
- The distance between the choke valve and the body casting should be 0.050 in. (1.27mm).
- If an adjustment is necessary, turn the valve using a screwdriver.
FAST IDLE AND CHOKE VALVE ADJUSTMENT
- Position the end of the idle adjusting screw on the next to highest step of the fast idle cam.
- A 0.050 in. (1.27mm) feeler gauge should slide easily between the lower edge of the choke valve and the carburetor bore.
- If necessary, bend the choke rod until the correct clearance is obtained.
- Open the throttle to the wide open position.
- A 0.230/0.270 in. (5.842/6.858mm) gauge should slide freely between the lower edge of the choke valve and the bore of the carburetor.
- If necessary, carefully bend the throttle tang to obtain the proper clearance.
VACUUM BREAK ADJUSTMENT
- Hold the diaphragm lever against the diaphragm body.
- The clearance between the lower edge of the choke valve and the air horn wall should be 0.136-0.154 in. (3.454-3.912mm) on Powerglide cars and 0.154-0.173 in. (3.912-4.394mm) on manual cars.
- Bend the diaphragm link, if adjustment is necessary.
FLOAT LEVEL ADJUSTMENT
See Figure 2
- Remove the air cleaner assembly.
- Disconnect the fuel line, fast idle rod, cam-to-choke kick lever, vacuum hose at the diaphragm, and the choke rod at the choke lever.
- Remove the bowl cover screws and careful lift the cover off the carburetor. Use extra caution not to drop and loose the screws in the engine.
- Install a new gasket on the cover before making any adjustments.
- Invert the cover assembly and measure the float level with a float gauge.
Rebuilding kits include a float level gauge.
- Check float centering while holding the cover sideways. Use the same gauge as in Step Five. The floats should not touch the gauge.
- Hold the cover upright and measure the float drop. If the drop is more or less than 1 3 / 4 in., bend the stop tang until the drop is correct.
- Install the cover and carefully tighten the retaining screws, then reconnect the lines and linkage