Pontiac FIREBIRD 1972 Service Manual page 688

6B-34 1972 PONTIAC SERVICE MANUAL
ports are clean of all carbon deposits and that the
Check wear of throttle shaft bearing and throttle
seats for idle adjustment screws are not damaged. If
shaft. There should not be more than about .005"
ends of adjustment screws are grooved or bent, they
play between shaft and bearings, otherwise air leaks
should be replaced.
will interfere with performance. Make sure that
throttle valves are not bent and do not have burrs or
sharp edges.
ASSEMBLY A N D ADJUSTMENT OF W G D 2-BARREL CARBURETOR
During assembly of carburetor, use all new gaskets and
any additional new parts found to be necessary during
inspection.
Mount throttle body on fixture. If it was necessary to
remove the idle mixture needles, install the idle mix-
ture needles and springs into the throttle body until
finger tight. Back out screws 1 1/4 turns as a prelimi-
nary idle adjustment.
NOTE: Do not install the plastic idle limiter
caps furnished until after the idle mixture has
been adjusted on the engine. Refer to Section
6D for setting procedure.
Place new gasket on throttle body and install main
body.
Place a new pump inlet check ball in inlet hole and
install retainer firmly in seat.
Install pump outlet check needle point downward in
pump outlet well, then install a new gasket, the dis-
charge jet housing and screw. Install both metering
rod jets (no gaskets used).
5. Install vacuum piston spring. Install lower pump
spring and pump plunger assembly, using care to
avoid curling edges of plunger leather washer.
6. Install choke shaft assembly. Install choke valve with
markings up; use new screws. With screws slightly
loosened, close choke valve tightly to center it, then
tighten screws. Check for uniform clearance and free-
dom from sticking in all positions. Choke mechanism
is free if choke valve will fall open from its own
weight. If valve fits properly, support heads of screws
on a suitable steel block and stake opposite ends.
7. Install float needle seat and gasket. Use a large
enough screw driver to completely fill slot so as to
avoid damage to it. Install float needle, float and float
pin, leaving gasket off.
8. With air horn inverted, adjust float as follows:
(a) Check to see that float is parallel with outer edge
of air horn casting. Adjust, if necessary, by bend-
ing float arm.
(b) Place 5/16" Gauge between air horn and center
of float. If necessary, adjust float level by bending
float arm until float just touches gauge.
NOTE: When adjusting float, care must be ex-
ercised to avoid pressing the flared tip needle
into the needle seat as a false setting may result.
Fig. 6 6 - 4 5 Installing Inlet Check Ball Retainer
Fig. 6 6 - 4 6 Checking Float Alignment