IDLE STOP SOLENOID (Fig. 26)
FIGURE 26
MAJOR SERVICE OPERATIONS ALL MODELS
DISASSEMBLY, CLEANING, INSPECTION AND ADJUSTMENTS
The following disassembly and assembly procedures may vary somewhat between applications due to specific design features. However, they will basically pertain to all Quadrajet models.
DISASSEMBLY
NOTE: Place carburetor on proper holding fixture such as BT-3553.
AIR HORN REMOVAL - (Figure 27)
1. Remove idle vent valve attaching screw; then remove.
idle vent valve assembly. If thermostatic vent valve is
used, remove dust cover, then remove valve. Care
should be used not to bend or distort the bi-metal strip.
2. On those 4MV models using the vacuum operated vent
switch valve, remove small screw from top of vent valve
plunger stem.
NOTE: Hold plunger stem with needle-nosed pliers to prevent turning and tearing of diaphragm. Remove vent valve cover screw and air horn screw and carefully lift cover from air horn. Remove cover gasket, vent valve assembly, and spring noting position of the vent valve for later reassembly. Remove diaphragm retainer and diaphragm from the air horn by carefully moving the diaphragm stem back and forth.
3. Remove clip from upper end of choke rod, disconnect
upper end of choke rod from upper choke shaft lever.
Remove choke rod from lower choke lever in bowl by
working choke rod "up and down" until lower end of
rod is free from lever.
NOTE: On late 4MC models, remove upper choke lever from end of choke shaft by removing retaining screw.
4. Remove clip from upper end of pump rod; then
disconnect pump rod from pump lever. Wire vent valve
lever can be removed from pump lever if replacement is
necessary.
NOTE: On those models that do not use a retaining clip in the upper end of the pump rod, known as the "clipless" pump rod, using a pin punch, carefully drive the accelerator pump lever roll pin out of the boss only enough to lift pump arm out of the way. Then, disconnect pump rod from pump lever. CAUTION: Do not bend the pump rod to remove from pump lever; follow the above procedure.
5. On Chevrolet 4MV models using either a Combination
Emission Control (C.E.C.) valve or idle stop solenoid
mounted on the carburetor:
a. On C.E.C. valve models only, remove vacuum hose
from the C.E.C. valve and vacuum tube on the float
bowl.
b. Remove screw securing C.E.C. valve or idle stop
solenoid bracket to float bowl.
NOTE: Do not remove the bracket for the C.E.C. valve or idle stop solenoid from the air horn assembly unless replacement of the bracket is necessary.
CAUTION: Do not immerse the C.E.C. valve assembly or idle stop solenoid in any type of carburetor cleaner.
6. On other 4MV and 4MC models using an idle stop
solenoid mounted on the carburetor:
FIGURE 27
