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CARBURETOR-HOLLEY
14-1 1
time during engine warm-up. Adjust as follows:
(1) With the fast idle speed adjusting screw con-
tacting the step on the fast idle cam shown in (Fig.
ll), move the choke valve toward the closed position
with light pressure. Insert a
inch drill or gauge
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 link at the lower angle, using Tool T109-213, un-
til the correct valve opening has been obtained. Re-
fer to (Fig. 11).
When the correct fast idle position cam adiustment
has been made, the choke unloader (wide open
kick)
adjustment has also been obtained. No further
ad-
justment is required.
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 ma-
chine with a vacuum source or vacuum supplied by
another vehicle. Adjust as follows:
(1) With the engine
Not
running, open the throttle
valve 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. 12). (A minimum of 10 inches
of mercury (HG) will be required.)
(3) Insert a number 32 drill (170 cu. in. engine,
-
CLOSING PRESSURE ON
DRILL
O R GAUGE
A MINIMUM O F 10 INCHES
OF VACUUM ON
DIAPHRAGM STE
RETRACTED BY
NK670
Fig. 12-Measuring
the Choke Vacuum Kick Setting
CHOKE OPERATING LINK
NK671
I
-
w
Fig. 13-Choke
Operating Link Measurements
manual transmission), between the choke valve and
the wall of the air horn, or a number 42 drill (170 cu.
in. engine, automatic transmission) or a
(3/32
inch)
gauge in the above location. Use a number 32 drill on
the 225 cu. in. engine (manual transmission)
or
a
number
46
drill or gauge on the 225 cu. in. engine
(automatic transmission), as above. (Refer to (Fig. 12).
Apply sufficient closing pressure on the choke shaft
lever to provide the smallest choke valve opening
possible without distortion of the diaphragm link.
Note that the cylindrical stem of the diaphragm will
extend as an internal spring is compressed. The spring
must be fully compressed 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 can result if the link
is
not removed for the
bending operation.
(5) Remove the "E" clip and disengage the choke
operating link from the diaphragm stem (plunger),
CHOKE VALVE
WIDE OPEN
CHOKE LEVER
CHOKE VALVE
Fig. 14-Choke
Operating Link Clearances
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