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CARBURETOR-WWC3
14-55
made on the vehicle, as described in the Fast Idle
Speed Adjustment (On the Car) Paragraph. However,
the Fast Idle Cam Position Adjustment can be made
on the bench. This adjustment is important to assure
that the speeds of each step of the cam, occur at the
proper time during engine warm-up.
To make the fast idle cam position adjustment re-
fer to (Fig. 17), then proceed as follows:
(1) With the fast idle speed adjusting screw con-
tacting the step on the fast idle cam shown in (Fig.
17), move the choke valve toward the closed position
with light pressure. Insert a NO. 41 drill or gauge T109-
125 (Auto. Transmission or Manual Trans.) between
the choke valve and the wall of the air horn.
(2)
An adjustment will be necessary if a slight drag
is not obtained as the drill or gauge is being removed.
(3) If an adjustment is necessary, bend the fast idle
rod at the upper angle, using Tool T109-213, until the
correct valve opening has been obtained.
Vacuum
Kick
Adjustment
(This test can be made
ON
or
OFF
the vehicle.)
The choke diaphragm adjustment controls the fuel
delivery while the engine is running.
It
positions the
choke valve within the air horn by action of the link-
age between the choke shaft and the diaphragm. The
diaphragm must be energized to measure the vacuum
kick adjustment. Use either a distributor test machine
with a vacuum source, or vacuum supplied by an-
other vehicle.
(1) With the engine
Not
running, open the throttle
valves far enough to allow the choke valve to be
moved to the closed position.
(2) Disconnect the vacuum hose from the dia-
phragm and connect the hose from the vacuum sup-
ply, as shown in (Fig. 18). (A minimum of 10 inches
of mercury (HG) will be required.)
(3)
Insert a NO. 17 drill or gauge T109-205 (Manual
Trans.) or a NO. 35 drill (Auto. Trans.) between the
Fig.
1
%-Measuring the Vacuum Kick Setting
Fig. 19-Choke
Operating Link Measurement
choke valve and the wall of the air horn. Refer to
(Fig. 18). Apply sufficient closing pressure on the
choke shaft lever to provide the smallest opening pos-
sible, without distortion of the diaphragm link. Note
that the link must deflect a wire spring before
it
reaches the end of travel within the lever slot. The
link must travel to the end of the slot for proper
measurement of the kick adjustment.
(4) An adjustment will be necessary if a slight drag
is not obtained as the drill or gauge is being removed.
The adjustment of this opening will require the re-
moval of the choke operating link.
CAUTION: Damage to the diaphragm and the choke
lever slot can result if the link is not removed for
the bending operation.
(5)
Remove the clip and disengage the choke op-
erating link from the choke lever, then disengage the
link from the diaphragm stem. (The best bending re-
sults will be obtained by using a vise and a pair of
pliers.)
(6) Bend the choke operating link at the angle to
provide the correct choke valve opening.
CAUTION:
A
correction in the length of the link of
.010
inch, will result in a change of
.010
inch in the
choke valve opening.
As an example, if the choke valve opening is .010
inch in error, the correction in the link length would
be .010 inch.
A 2" micrometer will be helpful in establishing the
original length of the link, as shown in (Fig. 19)
be-
fore completing the adjustment.
(7)
Install the choke operating link and recheck the
choke valve opening, using a gauge or drill. Refer to
(Fig. 18).
Reinstall the vacuum hose to the diaphragm and
make the following check:
(8)
With no vacuum applied to the diaphragm,
some clearance should exist between the choke op-
erating link and the choke lever slot, in both the open
and closed choke valve positions, as shown in (Fig.
20).
NOTE: This
clearance
is
necessary to allow the
choke valve to close for starting
as
well as fully
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