Testing engineers of SEC VAZ Vladimir SEMAKOV, Vitaly VOLOKITIN, Pavel YEREMIN and the head of the laboratory Vladimir DORFMAN answer questions from readers.

I bought a VAZ 2109 with "euro" springs and decided to increase the ride height, replacing them with "native" ones. I purchased and installed the kit, but the car became too tall and stiff. It turned out that the front springs are about 20 mm longer than the Euro. Is this a fake? And how to distinguish the necessary springs from others?

It is likely that you got 2112 springs. They are more rigid than 2108, although they are 383.5 mm long (they are 19 mm longer than the “European” version). The spring can be “calculated” by the diameter of the rod from which it is wound; if it is 13.2 mm - spring 2112, if 12.9 - then spring 2108. For more details on springs for suspensions of VAZ cars, see ZR No. 5 for 1998.

If the main dimensions of your springs differ from those indicated, then they are, to put it mildly, “not original”. It is better to replace them with those provided by the design, that is, “relatives” of any type - standard or “European”. If in the latter case you are not satisfied with the vehicle’s ground clearance, then you can replace the racks with gas-filled ones. This will allow you to raise the body by 15–20 mm.

It was reported that some VAZ injection engines have a longer valve stroke than carburetor engines known to us. In a VAZ 2108 3 engine, valves cannot under any circumstances meet pistons, but is there such a danger in injection engines?

To begin with, the injection engines currently being manufactured do not differ from the carburetor in the valve stroke size. Your question, apparently, is associated with reports that the application of the “tenth” camshaft with extended valve timing is provided for in engines 21083-2110.

We hasten to assure that in this case the valve stroke increases by tenths of a millimeter and therefore their “meeting” with pistons on engines with a working volume of 1, 500 cm3 when the timing belt breaks is also impossible.

On the "Niva" release 1979 installed a VAZ 2121 3 engine (1.7 l). How to achieve normal operation of the tachometer and carburetor solenoid valve?

On its VAZ 2107 installed a 21213 engine and a single-point injection system. The engine runs without comment, but the tachometer, alas, no. How to fix it?

The 21213 engine is equipped with a Solex carburetor and a non-contact ignition system. Therefore, only a tachometer released no earlier than 1994 will be able to work normally with it. The Solex solenoid valve is not the same as the previous one, from the Ozone carburetor. The new one, the so-called actuator, is more sensitive to possible malfunctions, for example, of the control unit, because of its much lower inertia. Therefore, in cases of “vagaries” of the valve, it is necessary first of all to check the serviceability of the control circuit.

The signals for tachometers coming from the ignition devices of various systems (classical contact, non-contact and injection) are different in shape. In cars of the latest modifications, produced in injection and carburetor versions, tachometers are equipped with two inputs: low voltage for injection and high voltage for carburetor engines. In addition, the high voltage inputs are adapted to contactless and classic ignition systems.

Carefully inspect the back side of the instrument cluster 2107. If there is additional resistance on it on the right side (soldered between the contacts), for injection, you will need to reconnect the contact in the connector connected to the orange block from the middle left to the upper right (see diagram), i.e. from the high voltage input of the tachometer to low voltage. If there is no resistor on the instrument cluster, you will have to buy a new combination (with a resistor, tachometer 241.3813) and connect it with these changes.

Alteration of the old combination at home is impossible (because the matter is far from the resistor).

Is it possible to mix antifreeze and Tosol, as well as synthetic oils of various viscosities and different companies?

Antifreeze is the common name for non-freezing liquids intended for refueling automobile cooling systems. And Tosol is a brand of domestic antifreeze. Under the name "Antifreeze", as a rule, non-freezing liquids of foreign manufacturers are sold.

The antifreezes produced today are usually ethylene-based.

glycol, therefore, there are no fundamental contraindications to mixing such liquids of various brands and manufacturers. However, antifreezes include various additives, including anticorrosive and anti-foaming agents, and various dyes. Thanks to the latter, the color of antifreeze is green, blue, yellow, red. These additives and dyes may be incompatible and, when mixed, lose their abilities (fight corrosion, prevent foaming of liquids, etc.). In addition, a chemical reaction may precipitate, which can clog the radiator or any channel of the cooling system. Therefore, experiments on mixing different antifreezes are best done in a separate bowl.

The service life of antifreeze is three years or 60 thousand kilometers. So if, for example, you have to add it in the third year or at a run of 50 thousand km, and there is no liquid of the right brand on hand - it is better to fill in a new one, without forgetting to rinse the system with water before that.

For the same reason (each manufacturer has its own additives), do not mix oils - motor or transmission oils. In extreme cases, it is permissible to add oil, but not more than 15–20% of the main volume.

Which oil is preferred for the VAZ 2108 gearbox? Is automatic transmission fluid suitable for her?

For over ten years, engine oils have been poured into front-wheel drive gearboxes, which are not too suitable for them (there were simply no special ones). Unfortunately, TM5–9P oil is not temporarily produced, therefore, when changing, we recommend using brands specially designed and approved for use in front-wheel drive VAZ gearboxes: Rexol T SAE 80W-85, API GL-4; LUKoil TM-4 SAE 80W-85, API GL-4. Omskoyl Trans P oils SAE 80W-85, API GL-4/5 can also be used; Yukos Trans P SAE 80W-85, API GL-4/5.