For more than 100 years the carburetor has been used formost gasoline cars. The work of this device is to prepare a mixture of air and gasoline vapor, which will enter the combustion chambers. Consider how the carburettor DAAZ-4178 works, find out its technical characteristics and learn how to regulate its operation.
A lot of UAZ car owners, as well as"Volga" with the 402-m motor are interested in the selection of carburetors for their cars. If we analyze all existing solutions on the market, then the best approach for these engines is from the Dmitrov aggregate plant.
The carburettor DAAZ-4178 for motorists is considered a very popular model. It allows you to significantly improve the dynamics of the engine, as well as with the correct setting leads to a lower fuel consumption.
These units are designed for cookingquality combustible mixture. Then the unit feeds it to the combustion chambers. The ratio of fuel in the mixture is directly proportional to the amount of air that passes through the device.
Ruler 4178 is a two-chamberemulsion systems. In general, the entire line, and carburetor DAAZ-4178-1107010-30 including, has the same device. In these carburetors all effective and well-proven technologies are applied. Here you can note the presence of a more balanced float chamber, a system of sequential opening of the dampers and other technologies.
The device is assembled from standard units andaggregates and practically does not differ from other designs. The carburetor consists of a main metering tank, an idling system, transient systems, a pump, an econostat and an EPHC.
Consider the purpose of each of the main systemsthis unit. This model is chosen by many motorists. Models with index 30 and 40 are suitable for "Volga" and UAZ. Owners of these machines speak very well about such devices. They have wide options for customization, as well as practically problem-free.
This system is designed to provide the necessarythe amount of fuel mixture at different operating modes of the motor. It is able to work with all modes, except idling. Thus, at a medium engine load, the dosing system is obliged to provide a lean fuel mixture of constant composition.
If we consider the device of the simplestcarburetor, and then take a look at the technical characteristics of the DAAS-4178 carburetor, then in the simplest design, as the throttle opens, the air through the diffuser passes more slowly than the fuel that gets into the chamber from the nebulizer. Thus the mixture is enriched. In order to prevent too rich a mixture, engineers have provided the possibility of compensating the ratio of the fuel mixture with the air ratio. The amount and volume of air can be adjusted by means of throttle valves. In carburettor units, such compensation processes are a dosing system.
In most models from DAAZ, these methodscompensation of the composition of the fuel mixture operate on the basis of pneumatic braking. So, fuel arrives, and then it is sprayed not from the float chambers, but through a special emulsion channel. This is a special tube. In the walls of the tube there are special technological holes. They facilitate the exit of air coming from above from the jet. There, in this channel, there is a process of mixing, and the mixture itself can leave these technological holes.
As the throttle opensdamper, the rarefaction and volume of the mixture increase. Also, the volumes of fuel passing through the jets and the amount of air increase. The amount of air is completely proportional to the volume of fuel. So compensation is provided.
In short, the GDS createsmotor all conditions for work on small, medium and high loads and modes. This carburetor DAAZ-4178-1107010-30 provides the engine with power stability and operation in all possible modes of operation.
For the engine idling at a minimum speedonly a very small volume of the mixture is required. In such conditions, a fully closed throttle is observed. But the level of rarefaction in the diffuser is not enough now to start the GDS.
That's just for this carburettor DAAZ-4178-30has in its design an idling system. Its task is the preparation of a mixture that allows to ensure stable operation of the engine with a fully closed flap.
Channels of the system unite a special cavity behindchokes and upper chambers. When the motor is running at idle, a sufficiently high vacuum is created under the damper. When it is exposed to the fuel comes from the channel for the emulsion into the channel of the system XX. The ratio of fuel to air in the mixture depends on the capabilities of jets.
Further the mixture gets into the chokes, where thenmixed with air. For this, there is a technological gap between the flap and the walls of the chamber. This gap can be adjusted with a screw that is mounted on the damper lever. This is a quantity screw, with the help of which the carburetor is adjusted DAAZ-4178-1107010.
The amount of the mixture that passes through the channel inzadrosselnoe space, can be adjusted with a special screw with a cone nozzle. This screw is responsible for adjusting the quality of the mixture. If you twist it, the channel cross-section is thus reduced.
If the throttle is opened moresmoothly, then significantly increases the amount of air, but the volume of fuel remains the same as it was. The GDS still does not enter into this process because of the lack of rarefaction. The result is a depleted mixture and a failure in the motor's operation.
For a smoother transition from idle tothe average mode of operation carburetor DAAZ-4178-1107010-40 is equipped with a special transitional system. It connects its channels to the channels responsible for idling. Here there is a special hole, which is designed in such a way that after opening the shutter, it enters the zone of maximum rarefaction. This channel also receives a little mixture into the chambers. Due to this, there is no abrupt transition between the operating modes of the motor.
At idle, when the flap is fullyclosed, there is an addition to the mixture of air. The composition is compensated by the presence of jets. If you twist the screw that is responsible for the amount of the mixture, then the flap will open. The gap between the flap and the chamber increases, and the amount of air decreases. At the same time, the crankshaft speed increases. If you unscrew the screw, the frequency will decrease. On such a device as carburetor DAAZ-4178, the adjustment is carried out by rotating the adjusting screws.
GDS carburetor is designed to provideUninterrupted operation only with a smooth process of opening the damper. If you open it more sharply, then the process of education is violated. In order to avoid a failure, the design has a special pump. It allows you to temporarily enrich the fuel mixture, if the throttle opens sharply.
When the engine starts, the crankshaft rotateslow revs. In the inlet chamber is a low enough vacuum, and the fuel evaporates very poorly at the same time. Also, if the motor is cold, the fuel vapor condenses in the intake tract.
To make the start-up process more stable, it is necessary that the DAAZ-4178-40 carburetor prepare a richer mixture. So, the air damper closes and the throttle opens.
To facilitate the motor start-up process, the carburetors are equipped with a special starting device. According to the principle of operation it is an air damper, as well as an automatic device that opens it.
This device is designed forwork at maximum loads to further enrich the mixture. It is a nebulizer, which is installed at the very top of the mixing chamber. Fuel in the econostat is fed through the channel where the fuel jet is installed.
In order for the motor to produce the maximum power, the mixture must be very rich.
To cook it, carburetorDAAZ-4178-1107010 and all other models are equipped with a so-called economizer. This system allows to provide additional amount of fuel, which enters the nebulizer. But it does not pass through the main fuel jet. To activate the economizer, a special drive is used.
This construction is more complicated, in contrast tofactory carburettor. It is also a two-chamber emulsion type carburettor. It features an improved and more balanced float chamber. To make the mixture of higher quality, the designers created a more improved channel with a swirler.
Stable motor operation at startup and with loadhere it is possible to provide a GDS. Advanced CXX supports more stable operation of the motor at the lowest possible speed of the crankshaft. This carburettor DAAZ-4178-1107010-40 allows for a smoother transition from idle to load.
To install this structure on your ownon UAZ, there will not be any complicated alterations. However, the installation requires a thicker gasket from the 126th carburetor. If you do an installation without a gasket, then there is a risk of breaking the pump drive.
How to install carburettor DAAZ-4178-1107010 oncar UAZ? First, you need to remove the air filter and body. Then the device is removed. For this, it is necessary to unscrew the studs from the collector and replace them with new ones and short ones. The electric valves are removed, and the on-site relay is mounted in their place. Next, a new carburetor is installed in place of the old one. Before this, it is necessary to lay two gaskets. Now, the union must be connected to the distribution hose using a hose. Then it's time to move on to installing the EPHC control circuit.
And at the last stage, the carburettor is adjusted for DAAZ-4178-1107010. So, with the help of special screws, you can achieve optimum engine performance.
Although the design of DAAZ-4178 slightly differs from other models of the Dmitrov plant, the adjustment will not cause any difficulties.
In order to adjust the operation of the carburetor,Use the adjusting screws that are responsible for the quality and quantity of the fuel mixture. So you can set the engine running at idle. Often, the idle operating modes are unstable, and without an appropriate setting the car will not go.
Next, we adjust the carburetor DAAZ-4178. The calibration process is a few simple steps. First you need to warm up the power unit well. The screw, which is responsible for the quality of the mixture on the carburetor, needs to be unscrewed almost completely, and then tighten approximately 2.5 turns.
The screw, which is responsible for the amount of fuel mixture,is necessary in order to set the speed. To do this, you need to rotate the screw until the revolutions are around 850-950. Further with the help of the same quality screw, we find the highest speed, then with another adjusting screw we will return again 900 revolutions. These actions must be repeated until the rotation of the quality screw will increase the crankshaft speed.
If the speed starts to fall, then you find the transition from a richer to a lean mixture. It remains only to tighten the quality screw and leave it at this point.
Now you can no longer touch the carburetorDAAZ-4178. Adjusting it is finished. But this is so, if you sharply click on the accelerator, the transition from the maximum speed to idle has passed normally. If this is not the case, then you need to slowly rotate the quality screw.
So, we found out what the carburettor of DAAZ-4178 has technical characteristics.