This valve is used to increase the frequency of rotation of the crankshaft during engine warm-up. When starting a cold engine, the additional air supply channel is opened by a rotary valve flap, which moves when the bimetallic spring is heated. As it warms up, the additional air supply channel gradually closes.
In addition, the supply of additional air is regulated by the pressure disk of the air quantity meter, the movement of which leads to a corresponding rise in the distribution plunger, which also contributes to an increase in the crankshaft speed (with closed throttle).
When starting a cold engine, an electromagnetic starting injector, controlled by a thermal time switch, atomizes additional fuel into the intake manifold.
Fuel to the starting nozzle is supplied directly from the dispenser-distributor under a pressure of about 4.7 kg / cm2.
The maximum operating time of the nozzle at a temperature of minus 20°C is 8 s. If the coolant temperature is above 15°C, the starting injector does not turn on.