Installing the fuel pump on the VAZ 2107 carburetor

During the operation of the "seven" one of the problem nodes is the fuel pump. Sometimes his malfunctions have to be fixed urgently, “on the road”. Therefore, it will be useful for each owner of the “Seven” to know how the VAZ 2107 fuel pump (carburetor) works, what its main problems are and how to repair it.

Functions and device of the fuel pump VAZ 2107 (carburetor)

The fuel pump is a key component of the engine power system. The pump's function is to feed gas from the fuel tank to the carburetor float chamber. The gasoline pump on carburetor models VAZ is installed on the side of the cylinder block, inside the engine compartment.

The specific design of the pump makes the fuel pump one of the weak points of the power system. Pollution and poor quality of gasoline, constant load, leading to natural wear of parts, often serve as a cause of unit breakage. As a result, the gas supply stops and the engine stops working.

Gasoline pump VAZ 2107 consists of the following parts:

Works fuel pump Vaz 2107 as:

reciprocating motion of the pusher is provided by the joint operation of the actuator cam and the return spring.
working membranes move, creating alternately pressure and vacuum in the working chamber;
when the pressure decreases, the exhaust valve closes, gasoline starts to flow from the gas line through the opening inlet valve;
when the pressure rises, the intake valve closes and gasoline is injected through the exhaust valve into the hose leading to the carburetor.

The reasons for the failure of the fuel pump VAZ 2107

Depressurization of the working chamber due to wear of the gasket. This leads to the outflow of fuel from the pump or the suction of air instead of gasoline.
The channels of the valves (intake and exhaust) are blocked, as a result of which the valves cease to function. The problem can be prevented by installing a fine filter in the fuel line before the fuel pump.
Worn and skewed valve parts. The result of skewing is the same as when valves are clogged, but it is rather difficult to identify and fix the problem.
The rupture of the working membrane. In the working chamber pressure drops cease to form, the pump loses its working capacity.
Damage to the safety chamber. Gasoline begins to enter the engine crankcase, where it dilutes the engine oil. If the problem is not noticed in time, the engine may jam.

Troubleshooting gasoline pump VAZ 2107

Before checking the fuel pump, it is advisable to stock up with M8 bolts or other products of the same diameter that can serve as plugs for fuel hoses.

To check the fuel pump VAZ 2107, you must perform the following steps:

Loosen the hose clamp that feeds gasoline to the carburetor and remove the hose from the choke.
Shut off the fuel hose so that fuel does not overflow from it.
Several times to swing the lever of the manual drive of the fuel pump. If a gasoline jet beats out of the outlet fitting, the fuel pump is operational. If not, the check should continue.
Loosen the intake hose clamp, remove the hose and plug it in the same way as before.
Close the inlet nipple with your finger and swing the hand lever several times. If there is a significant vacuum, the problem is not in the fuel pump. If the finger does not “stick”, it is necessary to remove and repair or replace the fuel pump.

Replacing the fuel pump VAZ 2107

The easiest way to restore the engine when the fuel pump breaks is to replace the last one. Replacing the fuel pump VAZ 2107 is as follows:

Repair of the fuel pump VAZ 2107

Repair the fuel pump VAZ 2107 instead of replacing it - a much more rational solution in terms of finance. To do this, remove the unit. The procedure for removing the fuel pump is described in the previous section “Replacing the fuel pump VAZ 2107”.

After the fuel pump is dismantled, you can begin disassembling it and inspecting parts for damage or wear.

It is worth starting with gaskets. The thickness of the gasket between the fuel pump and the thermally insulating plastic spacer must be greater than 0.3 millimeter. The gasket between the spacer and the cylinder block should be thicker than 0.8 millimeter.

The most common breakdown of the fuel pump is the breaking of the working diaphragm. To replace it, it is necessary to unscrew the cap bolt and pull the diaphragm assembly out (stem with fixed diaphragms). To replace them, simply unscrew the nut on the stem. You should also check the serviceability of the return spring and, if necessary, replace it.

When the cover is removed, a strainer becomes available, which should be cleaned of dirt and inspected for damage before re-installing.

The channels of the valves of the fuel pump should be cleaned and check that they did not become loose in the seats. If play is noticeable, the valve should be replaced. If the cause of the backlash in a broken seat, the fault cannot be eliminated. Only need to replace the fuel pump.

In some cases, the tightness of the working chamber of the fuel pump is broken due to deformation of the cover. In this case, you can try to pick up and install the whole cover from the old fuel pump.

It is possible to delve into history a bit, as we will now talk about why the fuel pump does not work on the VAZ 2107. And the conversation will be about the carburetor engine. Consequently, the fuel pump is driven by a rod installed in the cylinder head. But first you need to consider the design of the device and understand what can fail.

The main elements of the fuel pump VAZ 2107

Gasoline pump on the car VAZ 2107 has a body of two halves, something even looks like a shell. All the fun is hidden inside. Two valves that prevent the movement of gasoline in the opposite direction (to the tank), as well as the diaphragm. It is driven from the cam on the camshaft via a rod. When extruding the diaphragm, a vacuum is formed, due to which the inlet valve opens and the exhaust valve closes firmly.

When the diaphragm moves in the opposite direction (while in the pump housing there is a certain portion of gasoline), the inlet valve closes completely and the exhaust valve opens. And the fuel goes through the hose to the carburetor. The diaphragm has a complicated design, as it consists of several layers, and also includes springs, which facilitate the movement of the rod. However, from such a brief description it is clear that the elements in the design are not very many, the work of the fuel pump is based on the simplest laws of physics.

The main malfunction of the fuel pump VAZ 2107

The most frequent failures include excessive heating of the casing and elements of the pump. But this is only a symptom, the reason that the device does not work, lies a little deeper. If the fuel pump VAZ 2107 is heated, it is necessary to allow it to cool. Probably, you have repeatedly seen how drivers moisten a cloth with cold water and wrap a fuel pump. Yes, this is a real way out, and the fastest. But it should be noted that the price of the whole pump for the carburetor engine is about 600-700 rubles. And you can immediately put a new one and forget about the damage forever.

But what happens if the fuel pump VAZ 2107 overheats? After all, the mode of operation of the engine does not change, but suddenly, for no reason at all, he began to stall, he lacks gasoline, only a wet rag helps. And the thing is that there is a strong wear valve or diaphragm. And when the body overheats, gaps increase, or the valves are completely jammed. Therefore, when the diaphragm moves, both valves are either closed or open, their behavior is difficult to predict. And will only repair help? But this question should be considered in more detail.

Please note that the replacement of the fuel pump VAZ 2107 is not necessary if the car accelerates to a certain speed normally (or develops a certain speed value), and then begins to deaf, as if it lacks fuel. The reason lies in such a small element as the actuator stem. With its strong wear this behavior is obtained: fuel consumption becomes greater than the performance of the pump. It cannot be said that the VAZ 2107 gasoline pump does not pump, the carburetor simply does not receive the portion of fuel that it needs to operate in the current mode. Only the replacement of the rod will help, its price does not exceed 50 rubles.

Pump repair or replacement?

There are two ways to get rid of the malfunction of the fuel system. In the first place is expensive, but reliable - the replacement of the entire fuel pump carburetor VAZ 2107. The second is the installation of a repair kit. What is better? If your hand is full and you can carry out all the work perfectly, then, of course, it will be cheaper to put only new entrails. But if you are a driver who rarely encounters such difficulties, it is better to purchase a new device and install it on the car. The benefit of this procedure is simple - you need to unscrew the two nuts and loosen the clamps.

If the car engine does not start, then various factors may cause such consequences. One of these factors may be a gasoline pump, the main purpose of which is to pump gasoline into the engine from the gas tank. By car VAZ 2107 injector, fuel pump is much more reliable than the carburetor cars. Despite this, even on injection cars, the fuel pump can fail.

What is the device in question?

The fuel pump on the car VAZ 2107 injector is presented in the form of an electric motor with a pump that carries out the pumping of gas from the tank.

The design of the pump has an electric motor that is powered by a 12V automotive network. The design of the electric motor is presented from a rotor, brushes and a collector, which are constantly in gasoline. Many will think that such a power system of the VAZ-2107 car injector is quite dangerous, but not so simple.

Spark and gasoline - a dangerous compound that can lead not only to fire, but also an explosion. It would have happened, because sparking occurs in the electric motor of a gasoline pump if it were not for the fact that gasoline belongs to the category of liquids that do not conduct electric current. In addition, gasoline does not burn if there is no air, and the fuel chain is extremely closed. Thus, the design of the electric fuel pump on the car VAZ 2107 is presented.

About where the fuel pump VAZ 2107 is located is the injector, the car owners will find out only when there is a suspicion of its malfunction. On carburetor sevens, this device is located in the engine compartment near the engine. Many may think that on the injection sevens, this device is in the same place, but not. The device is located directly in the gas tank of the car, which simplifies the fuel pumping system. If you open the trunk and raise the mat, you can see its output tube. Such an arrangement of the device under consideration has simplified the process of pumping fuel, but thereby has complicated access and replacement of the product when it fails.

The principle of the device is quite simple. After the ignition key is turned, power is applied to the motor terminals, with the result that the pump pumps gasoline into the system until a certain pressure is generated. When the pressure is created, you can start the engine. When the start of the engine occurred, the fuel pump continues to function throughout the entire period of operation of the engine, while maintaining pressure in the fuel system. After the engine is shut off, the pressure in the system lasts for a while for several minutes, after which, if the engine does not restart, it decreases.

Causes of faults and their diagnosis

To find out the cause of the malfunction of the fuel pump, you need to pay attention to the characteristic signs. In this case, the diagnostics of the device in question is performed. The easiest way to check the fuel pump VAZ 2107 injector is to turn on the ignition and listen for characteristic noise. If the fuel pump does not pump fuel, then in the gas tank will not hear a characteristic buzz. The reasons can be various:

Faulty fuse. To do this, replace the fuse and check that the device has started to function.
Faulty relay. In the event of a faulty relay, there will be no voltage applied to the motor terminals, which means that the device will not function.
Damage to the power circuit of the motor. You need to check the integrity of the wiring. The wiring to the fuel pump may be damaged or there may be no ground contact.
Motor malfunction. It is necessary to check the product by removing it from the gas tank.
Pump malfunction. The motor will work, but fuel will not be supplied to the system.
Filter clogging.
Computer fault. You can not exclude a malfunction of the control unit.

If the electric motor is faulty, it will be powered, but the device will not function, and you will not hear the characteristic buzz in the gas tank area.

Assessment of the condition and performance of the component parts is carried out by checking the presence of voltage at the terminals of the electric motor. For testing, you can use a tester, a voltmeter or a 12V light bulb. The presence of voltage indicates a malfunction of the motor itself.

The pressure in the power supply system of the injection engine of the VAZ 2107 is checked with a pressure gauge. The manometer should be fixed to the oil-resistant hose with a diameter of 12 mm with a clamp. The second end of the hose is attached to the fuel pump choke ramp. Previously carried out removing the plug fitting and unscrewing the spool. Thus, it is possible to estimate the pressure delivered to the nozzles by the VAZ 2107. In this case, the pressure on the pressure gauge should be equal to 3 atmospheres.

It's time to change the fuel pump

Repair of the fuel pump VAZ-2107 is not carried out, as the product is not dismountable and must be replaced. Before resorting to replacement, it is necessary to make sure that the fuel transfer unit and not other elements are indeed defective.

It is important to know! Some craftsmen carry out repairs on their own, carrying out their careful opening. It is not recommended to do this, as the risks of fuel ignition are too high.

The most common causes of failure of the electric fuel pump:

The use of low-quality fuel.
The lack of periodic cleaning of the fuel mesh.
Long maintenance in the gas tank the minimum amount of fuel. If the fuel pump will often capture the air, then it will speed up its failure several times.

Before you replace the fuel pump, you want to release the pressure in the fuel system. To do this, fold the terminal from the device, and then start the engine. This procedure is carried out if the fuel pump before the replacement pumps fuel, but if not, then there will be no pressure in the system.

The process of replacing the product is as follows:

In order to avoid short circuits, it is required to open the "minus" terminal from the battery.
Unscrew the 4 screws, which fixed the gas tank cover. Remove cover.
Using a wrench, unscrew the clamp fastening bolt at “10”, thereby freeing the tank and providing access to the pump.
Unscrew the tube nipples with the key on "17".
Remove the power supply.
Unscrew all 8 nuts with which the fixation of the product is carried out. You will need to use the key on "7".
Carefully remove the cover along with the main product and the fuel level sensor float. If you can not remove the pump, you should use a flat screwdriver.
The receiving bag or coarse mesh is removed.

When installing a new product, it is important to ensure that the condition of the rubber gasket is correct, otherwise it should be replaced. The part is installed in the tank opening, after which the assembly process is performed in the reverse order of removal. In the end you want to check the operation of the product. To do this, start the engine, and then check the tightness of all compounds of the fuel system.