The article will talk about the VAZ-2109 fuel pump, and also consider the options for the execution of this unit in carburetor and injection engines. It is worth paying attention to the fact that these are completely different designs, not much similar to each other. But their function is the same - to ensure the normal value of pressure in the fuel injection system. So, what is the design of the pumps that are used in carburetor engines? This needs to be discussed in more detail.
Carburetor fuel pump
Its body consists of two halves - upper and lower. Moreover, a small lever is attached below, with the help of which gasoline is manually pumped into the line leading to the carburetor. At the same time, the VAZ-2109 gasoline pump works from the camshaft. The carburetor receives fuel in small jerks, in portions. This fills the float chamber, which acts as a buffer for fuel circulation. There is a diaphragm inside the pump. It is driven by a cam, which, in turn, is driven by a camshaft through a steel rod. On thethe camshaft has projections, thanks to which the movement of the rod is possible.
There are several basic malfunctions that are inherent in fuel pumps installed on carburetor engines. Moreover, most of the breakdowns are associated with the diaphragm. When heated, it begins to bend much worse, therefore, there is no pumping of gasoline. The VAZ-2109 gasoline pump has a rather simple design. Its price in stores is about 500 rubles. Therefore, it is much easier to replace it completely than to repair it. In most cases, it turns out to be ineffective, since the quality of the elements included in the repair kit is often extremely low. But often the stock fails. It is made of steel, but manufacturers don’t really think about quality, they don’t harden it. Consequently, very rapid wear occurs.
Injection engine fuel pump
It has a slightly different design, as it has an electric drive. The installation location of the fuel pump is in the tank, under the rear seat you can access it. The drive is electric, at the feet of the passenger in the front seat there is a fuse and a VAZ-2109 fuel pump relay. If the characteristic sound of starting the motor is not heard when the ignition is turned on, first check the integrity of the relay and fuse. And only after that you can make your way further - to the wiring and yourselffuel pump. The latter is a small pump with a filter (it is also popularly called "diaper"), as well as an electric motor that drives the entire structure. Please note that two lines are laid to the tank - one for supplying fuel to the rail, and the second for returning excess gasoline. Of course, the requirements for the lines are different - the return line must withstand less pressure.
Replacement and repair of the injection engine pump
To access the installation location of this fuel system element, you will need to fold down the lower part of the rear seat. To do this, just open the doors and pull the loop, which is located approximately in the middle of the seat. Closer to the right door is the installation location. You will see it right away, as there will be a cutout in the carpet and soundproofing. Set the cover piece aside and remove the plastic cover. Under it are the studs, to which the pump housing assembly with the level sensor is attached.
Using an 8 wrench, unscrew all the nuts and carefully remove the washers. Please note that before this, it is desirable to clean the entire upper part of the tank, which is visible from under the carpet, from dust and dirt. Then be sure to dismantle the two hoses that are connected to the pump. Only after that, carefully, trying not to damage the fuel level sensor, remove the VAZ-2109 fuel pump. Similar actions are performed when replacing the gasoline filter. To check the performance of the motor, you must directly apply to it(briefly) stress. This will tell you that the engine is in good condition. If it does not rotate, then it is best to replace it.