Pontiac FIREBIRD 1972 Service Manual page 673

ENGINE FUEL 6B-19
OVERHAUL AND ADJUSTMENTS
C.E.C. VALVE ASSEMBLY
REMOVE
1. Remove vacuum hose from the C.E.C. valve and
timed spark tube.
2. Bend back retaining tabs on lock washer; then
remove large C.E.C. valve nut and remove valve from
bracket.
NOTE: Do not remove C.E.
C. valve bracket
from the float bowl assembly unless replace-
ment of the bracket is necessary.
Complete replacement instructions are included in the
replacement bracket kit.
3. Remove the electrically operated idle stop solenoid
from the float bowl casting by screwing outward.
CAUTION: Do not immerse the C.E.C. valve
assembly in any type of carburetor cleaner.
AIR HORN
REMOVE (Fig. 68-20)
1. Remove fast idle cam from boss on float bowl by
removing attaching screw. Then, remove fast idle
cam from choke rod and choke rod from upper choke
lever. Note position of rod and cam for ease in re-
assembly.
NOTE: Upper choke lever is spun on end of
choke shaft and cannot be removed.
Fig. 68-20 Air Horn Assembly
2. Remove six air horn to bowl attaching screws (three
long and three short screws).
3. Remove vacuum break diaphragm unit from the air
horn casting. Then, remove the vacuum break hose assem-
bly and link from the thermostatic coil lever.
4. Remove air horn by lifting straight up, invert and
place on clean bench. Air horn to float bowl gasket can
remain on bowl for removal later.
The idle vent valve on the air horn assembly has been
replaced by a pressure relief valve disc. Under "AIR
HORN DISASSEMBLY", this valve disc need not
be removed from air horn top for cleaning. If the
valve is defective, air horn replacement is necessary.
DISASSEMBLE (Fig. 6 8 - 2 0 )
1. If desired, the choke valve and choke shaft can be
removed from air horn by first removing the thermo-
static coil lever from the end of choke shaft by remov-
ing attaching screw.
Remove the two choke valve attaching screws; then,
remove the choke valve and choke shaft from air
horn.
NOTE: The choke valve screws are held in
place by Loctite so it will be necessary to re-
stake or reuse Loctite during assembly.
2. No further disassembly of the air horn is necessary.
The pressure relief valve discs need not be removed
from the top of the air horn for cleaning purposes.
FLOAT BOWL
DISASSEMBLE (Fig. 6 8 - 2 1 )
1. Remove air horn to float bowl gasket. Gasket is slit
next to metering rod lever so that it can be slid over
lever for ease in removal.
2. Remove float from float bowl by lifting upward on
float hinge pin. Remove hinge pin from float arm.
3. Remove float needle, then remove float needle seat
and gasket.
4. Remove fuel inlet nut and gasket, then remove filter
element and pressure relief spring.