Choke Vacuum Kick

Fig. 5 Choke vacuum kick adjustment (Typical):

Test can be made on or off vehicle. If adjustment is to be made with engine running, back off fast idle speed screw until choke can be closed to the kick position with engine at curb idle. (Note number of screw turns required so that fast idle can be returned to original adjustment). If an auxiliary vacuum source is to be used, open throttle valve (engine not running) and move choke to closed position. Release throttle first, then release choke.
When using an auxiliary vacuum source, disconnect vacuum hose from carburetor and connect it to hose from vacuum supply with a small length of tube to act as a fitting. Removal of hose from diaphragm may require forces which damage the system. Apply a vacuum of 15 or more inches of mercury.
Insert gauge between top of choke valve and wall of air horn, Fig. 5. Refer to the specifications chart. Apply sufficient closing pressure on lever to which choke rod attaches to provide a minimum choke valve opening without distortion of diaphragm link. The cylindrical stem of diaphragm extends as the internal spring is compressed. This spring must be fully compressed for proper measurement of vacuum kick adjustment.
Adjustment is necessary if slight drag is not obtained when removing the gauge. Shorten or lengthen diaphragm link to obtain correct choke valve opening. Length changes should be made by carefully opening or closing the U-bend provided in the link. Improper bending causes contact between the U-section and the diaphragm assembly. Do not apply twisting or bending force to diaphragm.
After completion of adjustment, reinstall vacuum hose on correct carburetor fitting. Return fast idle screw to its original location if disturbed. Make following check. With no vacuum applied to diaphragm, the choke valve should move freely between open and closed positions. If movement is not free, examine linkage for misalignment or interferences caused by bending operation. On 1983-85 models, adjustment is made by means of a 5/64 inch Allen wrench inserted into vacuum diaphragm.