Do-it-yourself adjustment of the VAZ-2105 carburetor: step-by-step video instructions

The carburetor on any vehicle is one of the components of the fuel system of an internal combustion engine. It mixes air with fuel liquid, and this mixture is supplied to the cylinders of the internal combustion engine. As you can see, this automotive part plays a very important role in the functioning of the vehicle as a whole. Therefore, the carburetor must be adjusted periodically. You will learn how to do this correctly on a VAZ-2105 from this article.

The first stage is setting up the float mechanism of the VAZ-2105 carburetor

First of all, to adjust the carburetor float mechanism, the car should be allowed to idle. And only after that begin the adjustment procedure.

The carburetor cover is removed.
The current level of fuel fluid in the chamber of the float mechanism is checked (its digital indicator should ideally be 28 mm).

If the digital indicator of the fuel level in the float chamber corresponds to the norm, then nothing needs to be adjusted. Otherwise, you need to do the following:

check the distance from the cover gasket and the float itself (this is done at the moment the needle valve ball comes into contact with it) - the norm is 6.5 mm (+- 0.25 mm);
bend the tongue;
check the maximum stroke of the valve needle - the norm is 8 mm;
check the distance from the cover gasket to the maximum retracted float - the norm is 14 mm (+- 0.5 mm).

If the indicators do not meet standard standards, they can be adjusted using a bracket. If the optimal level of fuel fluid in the float chamber was not obtained after adjustment, the needle valve will have to be replaced.

Work algorithm

Without a general understanding of the operating principle of a carburetor, it is difficult to repair and adjust it. Actions at random will not give a positive result or will cause more harm.

The principle of carburetion is based on the supply of fuel due to the vacuum created by the pistons of an atmospheric gasoline engine. Dosage is carried out by jets - parts with calibrated holes built inside the channels and capable of passing a certain amount of air and gasoline.

The operation of the DAAZ 2105 carburetor begins with a cold start:

The air supply is shut off by a damper (the driver pulls the choke lever), and the throttle of the primary chamber is slightly opened by a telescopic rod.
The engine draws the richest mixture from the float chamber through the main fuel jet and small diffuser, and then starts.
To prevent the engine from “choking” with a large amount of gasoline, the starting system membrane is triggered by the vacuum, slightly opening the air damper of the primary chamber.
After the engine warms up, the driver pushes the choke lever, and the idle speed system (IAC) begins to supply the fuel mixture to the cylinders.

On a car with a working power unit and carburetor, a cold start is performed without pressing the gas pedal with the choke lever fully extended.

At idle speed, the throttles of both chambers are tightly closed. The combustible mixture is sucked through a hole in the wall of the primary chamber, where the CXX channel exits. An important point: in addition to the dosing jets, inside this channel there are quantity and quality adjusting screws. Please note: these controls do not affect the operation of the main metering system, which operates when the gas pedal is pressed.

The further algorithm of the carburetor operation looks like this:

After pressing the accelerator pedal, the throttle of the primary chamber opens. The engine begins to suck in fuel through a small diffuser and main jets. Note: The CXX is not turned off, it continues to operate in conjunction with the main fuel supply.
When you sharply press the gas, the accelerator pump membrane is activated, injecting a portion of gasoline through the nozzle nozzle and the open throttle directly into the manifold. This eliminates “dips” in the process of accelerating the car.
A further increase in crankshaft speed causes an increase in the vacuum in the manifold. The force of the vacuum begins to draw in a large membrane, which opens the secondary chamber with traction. The second diffuser with its own pair of jets comes into operation.
When both dampers are fully open and the engine does not have enough fuel to develop maximum power, gasoline begins to be sucked directly from the float chamber through the econostat tube.

To prevent a “failure” from occurring when the secondary damper opens, a transition system is used in the carburetor. It is identical in structure to the CXX and is located on the other side of the unit. Only a small hole for fuel supply is made above the closed throttle valve of the secondary chamber.

The second stage - we adjust the starting device of the VAZ-2105 carburetor

At this stage, in a garage environment, a car enthusiast can perform the following steps to configure the carburetor system that starts and warms up the engine:

close the air damper (this is done using the thrust handle located in the car interior);
check the location of the rod shank, which must be at the end of the groove of the carburetor rod to start the system;
measure the gap level from the edge of the valve to the chamber wall (measurements are taken when the rod is recessed) - the norm is 5-5.5 mm.

If the digital indicators differ from the established standards, they are adjusted by rotating a special adjusting screw (it is located on the carburetor trigger).

Malfunctions and solutions

Adjusting the carburetor with screws does not help to get rid of problems and is done only once - during the setup process. Therefore, if a malfunction occurs, you cannot mindlessly turn the screws; the situation will only worsen. Find out the true cause of the breakdown, eliminate it, and then proceed to adjustment (if necessary).

Before you begin repairing the carburetor, make sure that the culprit of the problem is not the ignition system, the fuel pump, or weak compression in the engine cylinders. A common misconception: shots from a muffler or carburetor are often mistaken for a problem with the unit, although there is an ignition problem - the spark on the spark plug forms too late or early.

What malfunctions are directly related to the carburetor:

the engine does not start - it seizes and immediately stalls;
the engine does not idle;
“dips” when sharply pressing the accelerator pedal;
the power unit “does not pull” or functions unstable;
increased gasoline consumption, accompanied by black smoke from the exhaust pipe and the formation of soot on the electrodes of the spark plugs.

The listed problems have several causes, so it is proposed to consider them separately.

Difficulty starting the engine

If the cylinder-piston group of the VAZ 2105 engine is in working condition, then sufficient vacuum is created in the manifold to suck in the combustible mixture. The following carburetor malfunctions can make starting difficult:

When the engine starts and immediately stalls when cold, check the condition of the starter membrane. It does not open the air damper slightly and the power unit “chokes” from excess fuel.

Checking the fuel in the float chamber is done without disassembling: remove the air filter cover and pull the primary throttle rod, simulating the gas pedal. If there is gasoline, the accelerator pump nozzle, located above the primary diffuser, should spray out in a dense stream.

When the level of gasoline in the carburetor chamber exceeds the permissible level, fuel may flow into the manifold spontaneously. A hot engine will not start - it first needs to throw excess fuel from the cylinders into the exhaust tract. To adjust the level, follow these steps:

Remove the air filter housing and unscrew the 5 carburetor cover screws.
Disconnect the fuel line from the fitting and remove the cover by disconnecting the telescopic rod.
Shake out any remaining fuel from the element, turn it upside down and check the functionality of the needle valve. The simplest way is to suck air from the fitting with your mouth; a working “needle” will not allow this.
By bending the brass tongue, adjust the height of the float above the plane of the lid.

With the needle valve closed, the distance between the float and the cardboard spacer should be 6.5 mm, and the stroke on the axis should be about 8 mm.

Video: adjusting the fuel level in the float chamber

No idle speed

If the engine stalls at idle, look for the problem in this order:

The first step is to unscrew and bleed the idle fuel jet located on the right side of the middle part of the carburetor.

If the previous recommendations do not resolve the problem, try blowing aerosol fluid into the hole in the throttle body. To do this, dismantle the mixture quantity adjustment block together with the flange by unscrewing 2 M4 screws. Pour detergent into the opened hole, do not turn the quantity screw itself! If the result is negative, which happens quite rarely, contact a carburetor technician or completely disassemble the unit, which will be discussed below.

The culprit of unstable engine operation at idle speed is rarely the carburetor. In particularly advanced cases, air leaks into the manifold from under the “sole” of the unit, between sections of the housing, or through a crack that has formed. To detect and fix the problem, the carburetor must be disassembled.

How to get rid of "failures"

In the vast majority of cases, the culprit of “failures” when sharply pressing the accelerator pedal is the carburetor accelerator pump. To fix this annoying problem, follow these steps:

Place a rag under the lever pressing the pump membrane, unscrew the 4 M4 screws and remove the flange. Remove the membrane and check its integrity, replace it with a new one if necessary.

In old, heavily worn carburetors, problems can be caused by a lever whose working surface has been significantly worn out and does not press the “penny” of the diaphragm. Such a lever should be changed or the worn end should be carefully unfastened.

Small jerks when pressing the accelerator “all the way” indicate contamination of the channels and jets of the transition system. Since its device is identical to CXX, fix the problem according to the instructions presented above.

Video: cleaning the accelerator pump ball valve

Drop in engine power and sluggish acceleration

There are 2 reasons why the engine loses power - lack of fuel and failure of the large membrane that opens the throttle of the secondary chamber. The last breakdown is easy to detect: unscrew the 3 M4 screws securing the vacuum drive cover and get to the rubber diaphragm. If it is cracked, install a new part and reassemble the drive.

In the vacuum drive flange there is an air channel outlet, sealed with a small rubber ring. When disassembling, pay attention to the condition of the seal and change it if necessary.

If the secondary throttle drive is working properly, look for the problem elsewhere:

Using a 19 mm wrench, unscrew the plug on the cover (located near the fitting). Remove and clean the filter mesh.
Remove the unit cover and unscrew all the main jets - fuel and air (do not mix them up). Using tweezers, remove the emulsion tubes from the wells and blow in the washing liquid.

The reason for the lack of fuel may be a low level of gasoline in the float chamber. How to adjust it correctly is described above in the corresponding section.

Problems with increased gas consumption

Supplying too rich a mixture to the cylinders is one of the most common problems. There is a way to make sure that it is the carburetor that is to blame: at idle engine speed, fully tighten the quality screw, counting the revolutions. If the engine does not stall, get ready for repairs - the power unit pulls fuel from the float chamber, bypassing the idle system.

To begin with, try to get by with a little blood: remove the cover, unscrew all the jets and generously treat the accessible holes with an aerosol. After a few minutes (precisely indicated on the can), blow out all channels with a compressor developing a pressure of 6-8 bar. Reassemble the carburetor and do a test run.

An over-enriched mixture makes itself felt by black soot on the spark plug electrodes. Before the test run, clean the spark plugs, and upon return, check the condition of the electrodes again.

If local flushing does not produce results, disassemble the carburetor in this order:

Disconnect the fuel pipe, the gas pedal linkage, the starter cable and 2 tubes - crankcase ventilation and distributor vacuum.

The next task is to thoroughly wash all channels, chamber walls and diffusers. When directing the canister tube into the channel openings, make sure that the foam comes out from the other end. Perform the same operation with compressed air.

After blowing, hold the bottom part up to the light and make sure there are no gaps between the throttle valves and the chamber walls. If any are found, the dampers or lower block assembly will have to be replaced, since the engine draws fuel uncontrollably through the cracks. Entrust the operation of replacing chokes to a specialist.

When performing a complete disassembly of the DAAZ 2105 carburetor, it is recommended to perform the entire range of operations listed in the previous section: clean the jets, check and change the membranes, adjust the fuel level in the float chamber, and so on. Otherwise, you risk finding yourself in a situation where one breakdown endlessly replaces another.

As a rule, the lower plane of the middle block is arched due to heating. The flange must be ground in on a large grinding wheel, having previously pulled out the bronze bushings. The remaining surfaces should not be sanded. When assembling, use only new cardboard spacers. Reinstall the carburetor and proceed to setup.

Video: complete disassembly and repair of the Ozone carburetor

Third stage - idle speed adjustment

This stage is no less important than the previous two. To do this, the internal combustion engine is pre-started and warmed up. Only after this can the idle speed be adjusted.

The motor is brought out using rotational movements of the mixture quantity screw - the norm is 850 rpm:
to reduce the speed you need to rotate the quantity screw (to the desired level of 850).
Tighten the quality screw as far as it will go (rotational movements are performed until the motor stops shaking).
Unscrew the same screw in the opposite direction three turns.

In this way, the VAZ-2105 carburetor is adjusted at idle. Auto mechanics call all of the above actions calibration of the crankshaft idle speed.

Functions

The functionality of the element in question is quite simple. It is designed to enrich the incoming fuel mixture with oxygen and then remove it into the combustion chamber.

This whole process can be described by the term mixture formation. Its first stage is to introduce gasoline into the air stream, atomize it and partially evaporate it. Next, the mixture enters the intake manifold and cylinders, without ceasing to evaporate. The next stage is fuel dosing. After this, adjusting to the engine operating mode, the amount of mixture changes.

Expert advice

After completing the procedure for adjusting the VAZ-2105 carburetor device, experienced auto mechanics recommend paying attention to the following critical points:

Valve location - is in the retracted position, with the idle speed jet touching the seat in the carburetor body.
Lubricating the rubber seal with special motor oil.
The location of the air damper intended for cold passage is in a vertical plane, while the suction handle is lowered.
The condition of the solenoid valve - the presence of damage and malfunctions is checked as follows:
remove and put the connector on the valve;
listen to the sounds coming from the solenoid valve.

If clicks are heard during the inspection process, the part is in full working order.

How to clean the carburetor on a moped - step-by-step instructions

Cleaning is necessary if a lot of dirt and condensation has accumulated. To ensure that this procedure is not necessary, it is advisable to disconnect and disassemble the carburetor. If it is clogged, it is useless to perform adjustments.

First, turn off the fuel supply valve, then you need to disconnect the fuel and drain hoses from the carburetor.

Next, you need to disconnect the inlet pipe from the carburetor, then unscrew the throttle valve cover and remove it from the carburetor. Now the part is held in place only by two bolts, which can be unscrewed with a 10mm wrench. That’s it, the carburetor has been removed. It is advisable to disassemble it on a white table so as not to lose small parts.

Next you need to disassemble the carburetor. First, unscrew the bolts located on the carburetor body. After this, the protective cover will be removed.

Next, the float chamber is pulled out; it is held on one pin, which is removed from the grooves. It can be removed without using tools. Together with the camera, a small cylindrical part with a cone-shaped tip will be removed - a shut-off needle, which is held between the float and the fuel supply channel

It is important to ensure that it does not fall on the floor and get lost.

Now, using a screwdriver with a straight bit, unscrew the jets, the idle speed adjustment bolt and the mixture quality screw.

The unit is disassembled, you can proceed to cleaning. First, attach the tube attachment to the aerosol canister for cleaning.

The accumulated liquid is poured out of the carburetor cap, then the internal cavity is treated with a cleaning aerosol. The jets are treated in the same way; the aerosol tube can be lowered into the recesses and holes. Then all the internal cavities will be cleaned, and all the accumulated dirt will come out. An aerosol with a nozzle can be used to treat all other carburetor openings.

Small holes need to be blown out so that there is no dirt there.

The cleaned parts are wiped dry with a cloth; it is important to wait until the applied aerosol has completely dried. Then assemble the carburetor in reverse order

It is difficult to make a mistake during assembly, since all the parts differ in size and are placed only in certain holes.

Disassembled carburetor of an Alpha moped

When installing a float chamber, first attach an element that shuts off the fuel supply through the hole near the jets. A pin is connected to the camera mount, after which the entire structure is placed on the socket. Next, the cover is mounted and the bolts are tightened. Tighten the mixture quality screw one and a half turns, then tighten the idle speed screw.

It is recommended to spray the assembled carburetor to keep it clean on the outside. Next, the part is put in its original place, first the fuel hose is connected. Then you need to open the fuel valve and wait a few seconds until the fuel fills. You can now start the engine, but it may not start or may be too loud. This means that adjustment is necessary.

You can learn more about how to clean the carburetor on an Alpha moped from this useful video:

DIY repair

If you want to overhaul the engine yourself, pay special attention to the marks, which are needed even for ordinary simple operations, such as adjusting valves. Marks also allow you to correctly install certain parts and components.

A diagram or a detailed video, which you will find at the end of the article, will help you in your work. Regardless of the simple device, the VAZ 21053 engine must be assembled as accurately as possible. Of course, the engine should be repaired on a clean workbench so that particles that accelerate wear do not penetrate inside.

Remember that in some cases the markings are applied to the parts incorrectly, so even if the marks are compared, unstable operation of the unit may be observed. In this case, the part should be replaced or contacted by specialists with high-quality diagnostic equipment. You can always consult with experienced owners of VAZ 21053 cars, who should know the structure and features of repair work.

What models are installed on VAZ 2106/2107 cars

All types of carburetor mechanisms equipped with the VAZ 2106/2107 are aimed at reducing fuel consumption and giving the car maximum dynamism. In addition, an important role is played by such an indicator as environmental friendliness. For a decade, AvtoVAZ engineers gave preference to the most environmentally friendly types of carburetors.

Carburetors of three different models were installed on modern VAZ 2106/2107, as well as on cars produced in previous years:

Manufacturer: Dimitrovgrad Automobile Assembly Plant (or DAAZ). It should be noted that the company produced carburetors under license from Weber. Structurally, these devices were as simple as possible both in operation and in further maintenance. In addition, their main advantage was to provide excellent speed performance for cars of the sixth and seventh VAZ models. At the same time, DAAZ carburetors consume a very large amount of gasoline - from 10 to 14 liters per 100 kilometers.
Manufacturer: DAAZ, modification “Ozone”. This is a more advanced version of the first type of DAAZ, which has high environmental performance. The device provides good acceleration characteristics and consumes less than 10 liters of fuel per 100 kilometers. However, the disadvantage of this model is that it comes with a second camera. In its operation, a pneumatic valve plays an important role, which, in case of contamination or poor-quality adjustment, can stop the carburetor from working.
Manufacturer: DAAZ, modification 21053, which is produced under license from Solex. One of the most modern types of carburetors for equipping the VAZ 2106/2107. Maximum environmentally friendly and productive. It has a more complex design; the first in the DAAZ line is equipped with a reverse fuel supply system, which makes it as economical as possible. However, Solexes are demanding on the quality of gasoline - otherwise the fuel nozzles become clogged very quickly.

Modern VAZ 2107 models are equipped with this unit.

Common features in the design of carburetors for the VAZ Six and VAZ Seven

The carburetor mechanisms that are equipped with all VAZ 2106/2107 models throughout the entire production period of the car are two-chamber, that is, they have two internal combustion chambers. Structurally, all carburetors have three indivisible parts:

at the top there is a cover of the device, which protects the mechanism from dirt, and fuel fittings;
the middle part is a housing, inside which the chambers and diffusers themselves are located, transfers the air-fuel mixture to the engine;
The float compartment and throttle valves are located in the lower part.

In the operation of DAAZ carburetors, small parts are of great importance - gaskets, jets, float, economizer or dampers. All elements of the system are interconnected and failures in one part will inevitably lead to failure of the entire device.

The DAAZ carburetor on the VAZ 2106/2107 works according to the following principle:

Gasoline enters the float chamber through the inlet valve.
The required fuel level is regulated by the needle of the forced idle economizer or power stroke economizer - in any case, fuel enters the chamber in a strictly defined proportion.
Next, the fuel is sent to emulsion chamber No. 1 through nozzles.
In the chamber (or VBC), gasoline is crushed into small parts and mixed with air.
When the torque increases during acceleration, internal combustion chamber No. 2 may also be activated.
After the formation of the air-fuel mixture, the pump directs it to the diffusers, and through them to the engine.

That is, the main task of the carburetor is to form the air-fuel mixture in a strictly adjusted proportion to ensure smooth operation of the engine.

The presence of many small elements ensures reliable operation