1.- Correct diaphragm travel can
be obtained by adjusting the Return Check contact screw, in or out, until
the overall, length dimension of the contact screw and plunger is 15/16".
(See Figure 1). If the Return Check is already mounted on the carburetor,
make sure that the throttle lever is not bearing upon the end of the
contact screw as this might possibly depress the diaphragm slightly. When
turning the contact screw to arrive at the 15/16" length dimension, the
plunger must not be allowed to turn, otherwise the diaphragm may be
damaged. The plunger shaft incorporates two opposed "flats" upon which a
5/16" wrench may be placed to prevent turning, while the contact screw is
turned with a 3/8" wrench.
2. - When installing the Throttle
Return Check on the carburetor the extra length attaching screws (1" long)
must be used to insure adequate thread depth. With the mounting bracket
securely tightened in place make sure that the head of the contact screw
squarely lines up with the throttle lever. To obtain correct alignment, it
may be necessary to slightly bend the mounting bracket. Caution - Bend
only the bracket, not the Return Check housing.