6.1.11. Carburetors
On cars several types of carburetors with the falling stream are established.
The single-chamber carburetor 32 TL is installed on the engine of 1,2 l. Similar carburetors 32 PDSI and 1B1 are installed on engines of 1,3 l with low extent of compression.
The two-chamber carburetor 2E3 is installed on engines 1,3 with normal extent of compression. Butterfly valves of the carburetor open consistently. The butterfly valve of the secondary camera opens only at high turns of the engine under loading. Consecutive opening of butterfly valves provides high economy of fuel at smooth acceleration and uniform motion, and also provides the maximum engine capacity by full pressing of a pedal of an accelerator. The control of the secondary gate is made by vacuum in primary camera. Diameters of elements of primary camera of the carburetor it is less, than secondary.
The system of idling of the carburetor works irrespective of other systems and is run by the screw of adjustment of quality of mix.
Calibration of the main jets is made so that the engine worked normally at a half-open butterfly valve. For ensuring giving of the required amount of fuel at the maximum acceleration the vacuum valve of the economizer is used. The valve gives additional amount of fuel at the maximum depression at completely open butterfly valves.
For increase in supply of fuel at acceleration the accelerating pump gives additional fuel to the main diffuser of primary camera. The control of the accelerating pump is made by a mechanical cam from draft of a butterfly valve.
The GM Varajet II carburetor installed on models of 1,6 l – two-chamber type, but the main fuel jet is run by the valve with a conic needle.
All carburetors have systems of idling and the accelerating pump which gives additional fuel to the carburetor at sharp opening of a butterfly valve.
In the presence of the automatic air gate the cover of the gate heats up an electric heater and during the operation of the engine is gradually closed. On the carburetor 2E3 the cover of the air gate heats up cooling liquid. If on the carburetor the automatic air gate of any type is installed, at start of the cold engine it is necessary to press an accelerator pedal several times.