Pontiac FIREBIRD 1972 Service Manual page 685

ENGINE FUEL 6B-3 1
ADJUSTMENT OF FAST IDLE CAM, CHOKE UNLOADER AND FAST IDLE TANG
If the engine operates on fast idle too long after starting
or else moves to slow idle too soon, or the choke unloader
does not operate properly, check the following adjust-
ments with the carburetor either on the engine or on the
bench:
Remove air cleaner. Open throttle to clear fast idle
cam and close choke valve. With choke valve held
fully closed and stop on fast idle cam against the
casting, there should be .005" minimum clearance
between inner and outer choke levers (Fig. 6B-38).
If there is not enough clearance between levers, bend
outer lever lug, using Tool 5-4552 (or needle nose
pliers) as required to obtain proper clearance (Fig.
6B-39).
NOTE: With choke fully closed, tang on fast
idle cam must clear stop on throttle body
flange.
Hold choke closed lightly. Fully open throttle, forc-
ing choke valve open.
Check clearance between upper edge of choke valve
and wall of air horn, using a 3/16" drill (Fig. 6B-40).
If clearance is not correct, bend the unloader arm as
required to obtain specified clearance.
With carburetor on engine, rotate fast idle cam so
that fast idle tang contacts high step of cam. Then,
adjust fast idle tang to obtain engine speed of 1500
R.P.M. with engine at normal operating tempera-
tures (Fig. 6B-41).
,005'' MINIMUM
CHOKE HELD
CLEARANCE
BETWEFN
FULLY CLOSED
- -
INNER AND
D l l T F R
BEND T O
ADJUST
Fig. 6 8 - 3 9 Adjusting Choke Lever Clearance
BFND LINLOADER
ANM
Fig. 6 8 - 4 0 Choke Unloader Adjustment
Fig. 6 8 - 3 8 Checking Fast ldle Cam Position
Fig. 68-4
1
Adjusting Fast ldle Speed (On Engine)