VAZ-2121 is a specific car. It has increased cross-country ability and can drive in places that owners of ordinary cars do not even dream about. It is used by hunters and fishermen, villagers and just lovers of impassability.
However, movement on roads with poor pavement, rough terrain leads to large dynamic loads on the body. Sooner or later, the time comes to strengthen the Niva spars.
Causes of body weakening
The design of the VAZ-2121 is quite rigid. It has a short base - 3740 mm and a width - 1680 mm, which prevents twisting well. The 3-door body further enhances rigidity. Despite the sturdy construction, cracks appear over time on the side members in the steering area, as well as in the places of attachment of the suspension arms. Why is this happening?
"Niva" a significant part of its mileage passes on the road, experiencing a constant impact, which is transmitted from the chassis to the side members of the car. Over time, these strokes lead to fatigue of the body metal. In addition, the protective mastic, with which the car is processed at the factory, moves away and exposes the metal surface. Corrosion appears. It further weakens the supporting elements.
The moment comes when the strengthening of the Niva spars becomes inevitable.
The main fault in the back of the car
In the rear of the body, the bracket for fastening the transverse thrust, more commonly referred to as the “soldier,” suffers more. Its correct position ensures the exact location of the rear axle relative to the front wheels. When the machine moves in a deep rut at a decent speed, this bracket experiences a shock load from lateral traction. Constant exposure leads to fatigue, and the metal weakens. There comes a time when a good blow is enough for the "soldier" to change his position. As a result, the running parameters are violated.
In addition to the above reasons, the spars can weaken as a result of an accident. Despite the fact that the geometric parameters are restored, the places in which they were deformed acquire a “memory”. Subsequently, they can bend in these places from a slight load.
Also, off-road enthusiasts are engaged in strengthening the Niva spars. They strengthen the body for installing custom chassis and accessories. For example, winches.
Preliminary work
Before proceeding with the repair of the side members, it is necessary to carry out preliminary work. It consists in preparing the working area and hanging the front of the machine on the stands.
Work on strengthening the Niva side members is best done on a viewing hole or on a lift.
Before starting welding work, remove the floor covering and remove the noise insulation that is adjacent to the motor shield. This is the place where the pedals are installed.
To do this, remove the plastic linings from the thresholds of the machine and fold the skin. Thus, it will be possible to control the absence of fire in the cabin. It is also necessary to release the upper suspension arm. To do this, disconnect the ball joint from the steering knuckle. Subsequently, this will allow the installation of a repair part on the side member.
Before work, it is necessary to clean the proposed welding spots. This will provide an opportunity to get good penetration, help to avoid ignition of polyurethane mastic.
Strengthening the front side members on the "Niva"
Before welding the repair kit, it is necessary to inspect the fastening of the beam on which the engine is mounted. It often happens that the nuts that fix the engine mountings are torn out of their seats. In this case, you need to separately hang the engine on the jack, remove the rubber cushions on which it is mounted.
Then you need to cut a window with a grinder in the spar, which will provide access to the nuts. Then the nuts are fixed by welding, the window closes, and is also brewed.
This must be done before the reinforcing plates are welded, because they will block access to these nuts, which will greatly complicate the repair.
There are two options for reinforcing the side members on the Niva 2121:
- To make a plate repeating in shape the outer part of the spar.
To do this, take a sheet of metal with a thickness of 2 to 4 mm. You can use a sheet of greater thickness, but in this case it will be difficult to fit to the profile of the spar. In order to properly cut it, you first need to make a piece of cardboard. A sheet of cardboard is applied to the side member, the boundaries of the future part are outlined. All holes are also marked along the way. After the pattern is ready, it is superimposed on a steel sheet and encircled with a marker. The part is cut with a grinder. After that, you need to drill holes in increments of about 5 cm. They will serve as electric rivets, that is, through them the part will be welded to the body.
- Purchase a ready-made kit for reinforcing the side members for the Niva.
They are already fully prepared for welding and do not require any further development. These parts are distinguished by different thicknesses of the metal from which they are made. The price of these amplifiers is about 3 thousand rubles.
Strengthening the rear side members on the "Niva"
Rear spars suffer from body aging. Corrosion eats through the metal, weakening it. They are sheets of iron, bent in the form of a U-shaped profile.
They can be strengthened either by brewing new spars on top of the old ones, or by reinforcing rotten places with a rectangular pipe. The second option is cheaper.
However, the main thing in reinforcing the rear end is not the spar, but the transverse link bracket. Before strengthening it, you need to take measurements of the position of the rear axle, and then install the bracket in the correct position. This is done with the help of hydraulic extensions. Only then can it be scalded.
Final work
In order to please the result of work for many years, it is necessary to protect the welding site from corrosion and impact of stones flying from under the wheels.
To do this, rubber-bitumen mastic is used, in which polymer chips are added. It is applied with a brush or a special spray gun connected to the compressor. Before applying the composition, the bare metal should be coated with soil. It must contain phosphoric acid, which protects the part from corrosion.