DIY repair of the front suspension of a VAZ 2131

In detail: do-it-yourself repair of the front suspension of a VAZ 2131 from a real master for the site my.housecope.com.

1 - brake disc;
2 - wheel hub;
3 - hairpin;
4 - lower ball joint;
5 - cap;
6 - housing of the outer hinge of the drive;
7 - adjusting nut;
8 - tapered bushing;
9 - hub bearings;
10 - oil seals;
11 - dirt reflecting ring;
12 - rubber cushion of the stabilizer bar;
13 - clip for attaching the stabilizer bar;
14 - rotary fist;
15 - body;
16 - stretching;
17 - a protective cover for the ball pin;
18 - upper ball joint;
19 - cushions for fastening the shock absorber rod;
20 - upper arm;

21 - cross member;
22 - adjusting washers;
23 - the axis of the upper lever;
24 - rubber-metal hinge (silent block) of the upper arm;
25 - rebound stroke buffer;
26 - bracket for rebound buffer;
27 - upper support spring cup;
28 - upper insulating spring gasket;
29 - spring;
30 - bolt for fastening the brace to the cross member;
31 - washers of the lower arm;
32 - axis of the lower arm;
33 - rubber-metal hinge of the lower arm;
34 - lower arm;
35 - bottom insulating spring gasket;
36 - lower support spring cup;
37 - compression stroke buffer;
38 - shock absorber;
39 - bracket for attaching the stabilizer bar to the body;
40 - stabilizer bar.

The front suspension is independent, on forked transverse steel levers, with helical coil springs, double-acting telescopic hydraulic shock absorbers and an anti-roll bar.

Undercarriage specifications
Image - DIY repair of the front suspension of a VAZ 2131

The upper and lower levers have a similar design: at the ends of the "fork" there are cylindrical lugs for rubber-metal hinges (silent blocks), and on the opposite side there is a platform with three holes for fastening the ball joint. On the front branch of the upper arm there is a bump against which the rebound buffer rests at the maximum suspension travel, and on the lower arm there are four holes for attaching the lower support spring cup. The ball joints of the upper and lower arms are interchangeable and unified with the upper ball joints of the rear-wheel drive VAZ suspension. The support is attached to the arm together with the boot and pressure plate by three bolts with lock washers and nuts. The threaded ends of the pins of both the upper and lower bearings point downward and fit into the taper holes of the steering knuckle. The pins are secured with self-locking nuts. Thus, the steering knuckle can rotate about an axis passing through the centers of the pins of the ball joints.

Video (click to play).

Some malfunctions of the front suspension
Image - DIY repair of the front suspension of a VAZ 2131

The axle of the lower arm is a bolt that passes through the bushing in the suspension cross member and the rubber-metal arm pivots. Just like the upper ones, the lower hinges are pulled between two washers, but another thrust washer (thick) is added between the inner washer and the bushing, adjacent to the bushing, and several shims (thin). The thickness of the washer pack is selected at the factory; when dismantling the suspension, it is necessary to remember their number and location. It is permissible to change the number and location of washers only when it is necessary to restore the suspension geometry (for example, after an accident, replacing the cross member, etc.). In this case, the distance between the outer washer and the flange of the rubber-metal hinge sleeve after tightening its nut should be within 3–7.5 mm. In the event that it is impossible to adjust the caster angle of the pivot axis (see below) with intact suspension parts, you can transfer some of the washers from one end of the lever to the other.

The suspension cross member is a curved steel tubular girder to which steel forged brackets are welded on both sides. In the lower part of the bracket there is a bushing for the axle of the lower arm, and the upper part is made as a vertical platform with four pairs of holes for fastening bolts. An upper pair of bolts secures the upper arm axle to the cross member. The second one from the top - pulls together the engine support bracket, cross member, spar and rebound buffer bracket. A third pair of bolts tightens the engine mount bracket, cross member, and upper suspension spring mount. And, finally, the fourth - the cross member and the upper support of the suspension spring. For reliability, the fastening nuts of the upper support of the suspension springs, after tightening, are welded to the protruding threaded part of the bolts.

Two brackets with holes are also welded to the lower rear part of the cross member. Stretch braces (steel rods) are bolted to them, increasing the longitudinal rigidity of the structure. The rear (threaded) ends of the guy wires are attached to the bracket on the car body with two nuts and washers. When installing the brace, the inner nut is tightened until the washer touches the bracket, and the outer nut is tightened with the recommended torque.

The suspension spring is supported by the lower insulating pad and the upper support cup. A rubber gasket is installed between the upper support cup and the upper spring seat. The upper support is pulled together by four bolts with a suspension cross member, two bolts - with a body side member (welded into the side member) and one more - with a rebound buffer bracket (the latter is welded into the support itself). The upper spring seat is also welded to the compression buffer support leg (facing downwards). The compression buffer at maximum suspension travel rests against the lower arm, the rebound buffer against the bump on the upper arm. The lower spring seat is attached to the lower arm with four bolts, nuts and lock washers. Brackets for attaching the lower end of the shock absorber and anti-roll bar (behind the spring) are also welded to the lower cup. Since a rubber-metal hinge is pressed into the shock absorber eyelet, it is possible to tighten the bolt of its lower fastening only on a car under load. The upper end of the shock absorber is fastened to the bracket on the car body with a nut and washers through two rubber pads. It can be tightened in any suspension position.

The anti-roll bar is a curved spring steel bar. It reduces the roll of the vehicle when cornering. Through rubber cushions pressed by steel clips, it is fixed at two points to the body and to the brackets on the lower support spring cups.

Suspension repair mainly consists of replacing worn and damaged parts. Pay particular attention to the condition of the protective covers of the ball joints (anthers). If they are torn, immediately replace the covers and grease, otherwise the support will quickly fail. The backlash in the upper support can be determined by swinging the wheel when the suspension is compressed (for this, place a shoe 230 mm high under the lower arm closer to the ball joint). To diagnose the condition of the lower hinge, remove the wheel and, pushing the mounting blade between the steering knuckle and the support housing, create an alternating load, probing the movement of the support pin through the boot. Replace rubber-metal hinges (silent blocks) when rubber bulges, tears, cracks or severe wear. When replacing the springs, make sure that they are of the same class (class A - unmarked, class B - with a black stripe on the outer surface of the coils, has a shorter length under load). It is allowed to install class A springs on the front suspension and class B on the rear, but not vice versa.

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1 - brake disc;
2 - wheel hub;
3 - hairpin;
4 - lower ball joint;
5 - cap;
6 - housing of the outer hinge of the drive;
7 - adjusting nut;
8 - tapered bushing;
9 - hub bearings;
10 - oil seals;
11 - dirt reflecting ring;
12 - rubber cushion of the stabilizer bar;
13 - clip for attaching the stabilizer bar;
14 - rotary fist;
15 - body;
16 - stretching;
17 - a protective cover for the ball pin;
18 - upper ball joint;
19 - cushions for fastening the shock absorber rod;
20 - upper arm;
21 - cross member;
22 - adjusting washers;
23 - the axis of the upper lever;
24 - rubber-metal hinge (silent block) of the upper arm;
25 - rebound stroke buffer;
26 - bracket for rebound buffer;
27 - upper support spring cup;
28 - upper insulating spring gasket;
29 - spring;
30 - bolt for fastening the brace to the cross member;
31 - washers of the lower arm;
32 - axis of the lower arm;
33 - rubber-metal hinge of the lower arm;
34 - lower arm;
35 - bottom insulating spring gasket;
36 - lower support spring cup;
37 - compression stroke buffer;
38 - shock absorber;
39 - bracket for attaching the stabilizer bar to the body;
40 - stabilizer bar.

The front suspension of the VAZ 2121 is independent, on forked transverse steel levers, with helical coil springs, double-acting telescopic hydraulic shock absorbers and an anti-roll bar.

The upper and lower levers of the VAZ 2131 have a similar design: at the ends of the "fork" there are cylindrical lugs for rubber-metal hinges (silent blocks), and on the opposite side there is a platform with three holes for attaching a ball joint. On the front branch of the upper arm there is a bump against which the rebound buffer rests at the maximum suspension travel, and on the lower arm there are four holes for attaching the lower support spring cup.

The ball joints of the upper and lower arms are interchangeable and unified with the upper ball joints of the rear-wheel drive VAZ suspension. The support is attached to the arm together with the boot and pressure plate by three bolts with lock washers and nuts. The threaded ends of the pins of both the upper and lower bearings point downward and fit into the taper holes of the steering knuckle. The pins are secured with self-locking nuts. Thus, the steering knuckle can rotate about an axis passing through the centers of the pins of the ball joints.

The suspension arms, in turn, can rotate on the axles within the range of the VAZ 2131 rubber-metal hinges (limited by their elasticity). The upper arm pivot has two holes and threads at both ends. Bolts pass through the holes that secure the axle to the suspension cross member. Washers are installed on the bolts between the axle and the cross member for adjusting the camber angles and longitudinal inclination of the axle of rotation of the wheels (see below).

The threaded ends of the axle fit into the rubber-metal hinges of the lever. Washers are located on both sides of each hinge: the smaller (flat) one on the inside, the larger one (convex outward) on the outside. The self-locking nuts of the upper arm axle are finally tightened only when the suspension is compressed (on a loaded car), otherwise the hinge will not be installed correctly and quickly fail.

The axle of the lower arm is a bolt that passes through the bushing in the suspension cross member and the rubber-metal arm pivots. Just like the upper ones, the lower hinges are pulled between two washers, but another thrust washer (thick) is added between the inner washer and the bushing, adjacent to the bushing, and several shims (thin). The thickness of the washer pack is selected at the factory; when dismantling the suspension, it is necessary to remember their number and location. It is permissible to change the number and location of washers only if it is necessary to restore the suspension geometry of the VAZ 2121, Niva 2131 (for example, after an accident, replacing the cross member, etc.).

In this case, the distance between the outer washer and the flange of the rubber-metal hinge sleeve after tightening its nut should be within 3–7.5 mm. In the event that it is impossible to adjust the caster angle of the pivot axis (see below) with intact suspension parts, you can transfer some of the washers from one end of the lever to the other.

The cross member of the VAZ 2121 suspension is a curved steel tubular beam, to which steel forged brackets are welded on both sides. In the lower part of the bracket there is a bushing for the axle of the lower arm, and the upper part is made as a vertical platform with four pairs of holes for fastening bolts.

An upper pair of bolts secures the upper arm axle to the cross member. The second one from the top - pulls together the engine support bracket, cross member, spar and rebound buffer bracket. A third pair of bolts tightens the engine mount bracket, cross member, and upper suspension spring mount. And, finally, the fourth - the cross member and the upper support of the suspension spring. For reliability, the fastening nuts of the upper support of the suspension springs, after tightening, are welded to the protruding threaded part of the bolts.

Two brackets with holes are also welded to the lower rear part of the cross member of the niva 2121. Niva 2131 stretch marks (steel rods) are bolted to them, increasing the longitudinal rigidity of the structure. The rear (threaded) ends of the guy wires are attached to the bracket on the car body with two nuts and washers. When installing the brace, the inner nut is tightened until the washer touches the bracket, and the outer nut is tightened with the recommended torque.

The spring of the suspension of the Niva 2121 rests on the lower insulating gasket and the upper support cup. A rubber gasket is installed between the upper support cup and the upper spring seat. The upper support is pulled together by four bolts with a suspension cross member, two bolts - with a body side member (welded into the side member) and one more - with a rebound buffer bracket (the latter is welded into the support itself). The upper spring seat is also welded to the compression buffer support leg (facing downwards).

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The compression buffer at maximum suspension travel rests against the lower arm, the rebound buffer against the bump on the upper arm. The lower spring seat is attached to the lower arm with four bolts, nuts and lock washers. Brackets for attaching the lower end of the shock absorber and anti-roll bar (behind the spring) are also welded to the lower cup.

Since a rubber-metal hinge is pressed into the shock absorber eyelet, it is possible to tighten the bolt of its lower fastening only on a car under load. The upper end of the shock absorber is fastened to the bracket on the car body with a nut and washers through two rubber pads. It can be tightened in any suspension position.

The anti-roll bar is a curved spring steel bar. It reduces the roll of the car Niva 2121 when cornering. Through rubber cushions, pressed by steel clips, it is fixed at two points to the body and to the brackets on the lower support spring cups.

Niva 2131 suspension repair mainly consists of replacing worn and damaged parts. Pay particular attention to the condition of the protective covers of the ball joints (anthers). If they are torn, immediately replace the covers and grease, otherwise the support will quickly fail. The backlash in the upper support can be determined by swinging the wheel when the suspension is compressed (for this, place a shoe 230 mm high under the lower arm closer to the ball joint).

To diagnose the condition of the lower hinge, remove the wheel and, pushing the mounting blade between the steering knuckle and the support housing, create an alternating load, probing the movement of the support pin through the boot. Replace rubber-metal hinges (silent blocks) when rubber bulges, tears, cracks or severe wear.

When replacing the springs, make sure that they are of the same class (class A - unmarked, class B - with a black stripe on the outer surface of the coils, has a shorter length under load). It is allowed to install class A springs on the front suspension and class B on the rear, but not vice versa.

Spacer over the top ball 40mm. under the platform 30mm, 28mm, 23mm, 11mm. Shock absorber gas oil KYB excel-g shniva.

Operation of the front suspension of the Niva in extreme conditions.