Vaz -21213 Repair Manual page 50

Fig.2-85. Accelerator pump:
1 - atomizer; 2 - fuel delivery ball valve; 3 - diaphragm; 4 - pushrod; 5 - operat-
ing lever; 6 - cam; 7 - primary throttle valve; 8 - non-return ball valve; 9 - sec-
ondary throttle valve
Fig.2-86. Choke pull-down unit:
1 - diaphragm; 2 - adjusting screw; 3 - diaphragm rod; 4 - choke control lever; 4.1 - lever 4 bottom profile to restrict maximum choke opening; 4.2 - top profile to ensure
choke mechanical opening ; 4.3 - lever 4 edge to ensure primary throttle starting clearance; 5 - choke valve; 6 - choke lever; 7 - choke return spring; 8 - choke cable; 9
- adjuster screw stop; 10 - primary throttle opening adjuster screw; 11 - throttle lever; 12 - primary throttle; Ç - choke starting clearance; ë - throttle starting clearance
50
engine speed. Inner profiles 4.1 and 4.2 operate choke lever 6
allowing choke opening to a certain amount at intermediate posi-
tions of lever 4. Rotation of choke lever 4 anticlockwise causes
the wider slot to release choke lever 6 stud; the choke is held in
a fully closed position by return spring 7. At the same time the
primary throttle is opened by means of lever 4 edge 4.3.
Choke 5 shaft is not centralized, therefore, after the engine is
started, the choke is opened by force of air flow, extending spring
7 to result in a leaner air-fuel mixture.
Vacuum from the throttle body operates diaphragm 1 and
opens the choke by means of rod 3. Adjuster screw 2 makes pos-
sible to control the degree of the choke opening.
The maximum choke opening rate at the engine start-up and
warm-up depends on choke lever 4 positions or choke lever slot
width.
Idling overrun control unit disables the idling system on
the overrun (during engine deceleration, downhill movement or
gear shifting) thus improving fuel economy and reducing CO
emission to atmosphere.
On the overrun at over 2100 rpm and carburettor idle switch
7 shorted to «ground» (Fig.7-40) (throttle pedal released), fuel
cutoff solenoid 4 is disactivated to shut off fuel supply. When the
idle switch is not grounded, the solenoid will not be disabled.