Suspension knocks - we carry out independent diagnostics of problems. Diagnosis of the running gear of a car: how it is done How to check the running gear for a vaz

The suspension is a very important part of a car. Your safety, driving control and comfort depend on its condition. Knowing how suspension diagnostics are carried out with your own hands, you can save a lot on car services, where very good money is taken for this procedure.

It does not happen that the suspension parts fail at one moment (of course, if you do not fly into the curb, or even much worse). Usually the suspension breaks down gradually. First, one element begins to tap on bumps, since it no longer works properly, its load falls on other elements that are not designed for this. They wear out faster. All this grows like a snowball, and in the end, all this results in a malfunction of the front and rear suspension and a lot of money.

To avoid this, we will consider the most important topic - do-it-yourself car suspension diagnostics. You can print this article and hang it in your garage as a reminder, and if you suspect something is wrong with the suspension, check it right away and don’t put it off.

There are a huge number of options for the execution of car suspension. The differences lie in the driving characteristics and the price of maintenance and of course its condition. The main structural elements remain unchanged.

The main elements of the suspension include:

• shock absorbers
• Levers
• Springs
• ball joints
• Shrus
• wheel bearings
• Stabilizer's pole

Let's take a closer look at how the car's suspension is checked, and identify its malfunction, if any. Let's start with springs and dampers.

shock absorbers

Telescopic strut shock absorbers play a very important role in the car - they dampen body vibrations and are responsible for the stability of the car on the road when performing maneuvers.

Checking the performance of shock absorbers is quite easy. To do this, take and shake the car when it is on a flat surface. After stopping trying to rock the car, it should stop. If the rear shock absorbers or the front ones are faulty, it will continue to wobble.

With faulty shock absorbers, it becomes problematic to operate the car. One feels the lack of assembly of the car, and breakdowns on some bumps.

Be sure to drive the car into a pit or overpass, and see if there are smudges on the shock absorbers - if there is, then the shock absorber is not in order, and it should be changed.

For a deeper analysis of worn parts, you need a special vibration stand for suspension diagnostics. You won’t be able to assemble such a stand with your own hands, and it will also be expensive to buy it for private use, so it’s best to fork out a few hundred rubles and contact the service to perform this procedure.

Springs

The next step in the chassis diagnostics will be the diagnostics of the springs. It starts with their visual inspection. If the spring is cracked, or worse, burst, then it must be replaced. Particular attention should be paid to the coils of the spring. If they are close to each other, or even touch, this indicates that the metal of the spring is “tired”, it is better to change such a spring.

It is also worth measuring the clearance of the car and comparing it with the clearance of which it was from the factory, if it is less, then the springs sagged.

With faulty springs, the car will roll, there will be rolls in corners, breakdowns in the suspension. Driving such a car will be difficult.

Basically, springs become unusable for natural reasons. If the car was a workhorse, various weights were carried on it, then this can cause premature wear.

In large cities, reagents adversely affect the properties of the spring, causing corrosion and thereby reducing the thickness of the coil.

Ball

In order to make the diagnosis of the suspension more complete, it is necessary to check the ball joints. The ball joint is the element that connects the movable hub and the non-movable suspension arm. Ball joints often fail due to fast driving on bad roads.

If there is wear on the ball joints, a dull sound will be heard. It will be especially pronounced when driving over bumps.

You can accurately diagnose ball joints using two methods:

1. side to side swing method. To do this, you will need an assistant who will check the knock in the area of ​​\u200b\u200bthe wheel during buildup. If it is, do not rush to sentence the ball joints, check the second method.
2. To implement the second method, it is necessary to jack up the car, observing safety methods. To eliminate the possibility of bearing play, you need someone to press the brake pedal. At this moment, you need to shake the wheel by holding the upper and lower points (as on the dial of hours 12 and 6). If you feel a noticeable backlash, then the support needs to be changed.

Stabilizer supports and struts

Stabilizer struts most often than all other suspension elements fail. Their malfunction is expressed in a distinct rattling and tapping on bumps.

If, when you release the steering wheel, the car throws out of the rut, you have to constantly steer and align it, this indicates that the stabilizer struts are faulty.

In order to check the stabilizer bar, you need to grab it with your hand, or find a stop and shake it with a crowbar. If loosening occurs without much effort, a knock is heard or play is felt, then the rack must be changed.

steering rack

The steering rack often starts to knock when driving at high speed on bad roads. The knocking of the steering rack indicates that it needs to be repaired as soon as possible. If this is not done, then in the future you can get to replace the steering rack, and this is very expensive.

The steering rack often starts to knock on cars that have a very stiff and clamped suspension. It does not dampen the full force of the impact, and part of the impact falls on the steering rack. Special crackers are installed in the steering rack, which are needed so that the shaft does not play. Over time, these crackers wear out, and constant shocks that the suspension does not dampen speed up this process. Reika starts to knock. The knock is very similar to the knock of the stabilizer struts.

To check the rack, you need to climb into the pit, or remove the wheels, and pull the rack shaft, first on one side then on the other. If you feel a beating, then you need to repair the rail.

It will also be useful to know that one of the characteristic signs of this malfunction is recoil to the steering wheel when driving over bumps.

Steering rods and tips

Symptoms of defective tie rod ends can be compared to the symptoms of a faulty steering rack, namely, there is a knock when driving over bumps.

In order to accurately diagnose the failure of these elements, it is necessary to visually inspect the rubber parts; if they are cracked or torn, then it is likely that these parts are faulty.

You can check these elements for play by swinging the mount up and down. If you feel a noticeable backlash, then most likely the ball bearings of the steering rods or tips are worn out.

Hub bearings

If the hub bearings are faulty, they give out a hum that appears when driving. This hum becomes very audible when driving on a flat road at one speed.

To be sure that this is the hub bearing, and not some box bearing, you need to slightly disperse the car, turn off the gear so that the car coasts. If our fears are confirmed.

In order to find out which bearing is buzzing, you need to raise the car on a jack and spin the wheel, if you feel a characteristic rattle of the bearing, then this bearing is faulty.

When the situation is very neglected, the wheel has play in the vertical plane. The more the bearing is worn, the more play there will be.

CV joints

Most often, a faulty CV joint shows itself with a distinct crunch with the steering wheel turned in any direction when starting off sharply. When this symptom is observed in a car, it makes sense to drive the car into a pit and check.

In order to check the CV joint yourself, you first need to perform a visual inspection, if the anthers are torn, it is likely that the CV joint is faulty, since the dirt that will fly under it will act as an abrasive and accelerate wear several times.

Outcome

The above is not all that is included in the diagnosis. These procedures will help to find out only the general condition of the main suspension units. For a deeper analysis of the wear of a particular element, equipment may be required that is only available at service stations.

One of the most common car problems in Russia is suspension failure. Chassis parts don't stand up to the local roads, obstacles and riding styles. Therefore, sometimes you have to turn to specialists and repair the car for further operation. Sometimes problems occur that do not require professional intervention at all. It is possible that the knock in the suspension comes from an unscrewed wheel or a loose hub mount. In this case, you need to remove the wheel and carry out basic diagnostics. Everyone can do it without any problems. If you have a little time and desire to find out what exactly is wrong with your car, you can carry out this procedure. If the suspension knocks, it is not necessarily the parts of the chassis that are to blame. Very often the culprit is the gearbox or even the engine mounts.

Therefore, the diagnostics are often delayed, it is necessary to open the hood and move all the parts with your hands that can loosen the fasteners and knock during the trip. This applies to every element, including the power unit. Engine mount problems are fairly common. When they fail, the power unit begins to stagger in its place of attachment and emit very unpleasant knocks while driving. Tighten all fasteners in the chassis. The upper shock mount can be loose, which will cause a frank knock in the suspension even on a flat surface. The hub nut should be properly tightened, which is responsible for holding all the suspension parts in place normally. Let's talk in more detail about all the revision processes.

Tighten all nuts and bolts if the suspension starts to knock

There are many cases when, after repairs in the garage workshop, the chassis begins to actively knock. It often turns out that the masters did not have a very professional hand. They did not tighten one of the fasteners, or did the wrong tightening. As a result, the part knocks hard during the trip or quickly fails. In this case, you need to put the car in the pit yourself and carry out several important works:

• climb under the engine area into the pit and feel with your hands all the suspension parts for backlash and knocks, pay special attention to bushings and silent blocks, fasteners;
• the lower shock absorber mount may go down a little, which will cause a certain sound, as if something will now fall off when driving on rough roads;
• steering tips and rods should also be tightened well enough, as well as other parts, if play is found, you need to try to tighten the element;
• if it is impossible to tighten it, it is worth going to specialists and changing the part, since further operation often turns out to be very dangerous and undesirable;
• you can also tighten the upper mounts of the struts under the hood, they often go down and start knocking even on a flat road when picking up or slowing down.

A knock on a flat road is especially incomprehensible to a car driver. If the suspension rattles when accelerating or braking, you should pay special attention to the racks. If jerks and knocks occur directly at the moment the gas or brake is pressed, pay attention to the outer and especially the inner cv joints. They can be checked by holding the axle shafts with your hand and checking the play. Often they turn out to be a big suspension problem that needs to be fixed urgently.

We check all the details of the suspension with our own hands - how to diagnose?

Self-diagnosis of any elements of the car, including the suspension, is quite possible, but brings a number of difficulties. First, you will need a pit to set up the car and get a good view. Secondly, you need to know everything you need for diagnostic work on your car model. There is a certain universal range of tasks that can be used to diagnose a car:

• first, put the car in a pit and lower yourself under the engine compartment to access the front suspension, manually examine the axle shafts for play;
• inspect all anthers to find any possible problems with CV joints or ball joints, then take a pry bar and check the condition of the bushings;
• to check the bushings and silent blocks, simply pry them gently with the flat edge of the mount and shake them, if there is a knock or too much travel, you need to replace them;
• also below, under the car, look at the fastening of all other parts that will help you make sure that it is the suspension that is knocking, and not the unscrewed engine;
• on the rear suspension, you should pay special attention to the silent blocks of the beam or to the levers, which depends on the design of the chassis in your car, the diagnosis is simple.

If you conduct such a study in advance in a car, you can easily find the main problems and malfunctions. Some parts can be easily repaired on their own. But sometimes it turns out that self-repair is impossible. It is necessary to contact a quality service and order a replacement for a specific part, which will be cheaper than diagnosing and identifying a problem, and then only replacing it.

What problems can not be postponed until later?

Driving a car with broken suspension is a bad idea. The driver must understand that he is exposing himself to a certain danger. There are many solutions that can be used in a wide variety of situations. If you find a simple problem, but don’t have a lot of money for repairs, you can temporarily install cheap Chinese spare parts and give yourself a few months of safe car operation. But it’s better not to joke with the following breakdown options:

• everything related to the racks and their fastenings - failure completely will not allow you to operate the car, and can also damage some surrounding parts;
• CV joints and their fastening mechanisms - they should be changed immediately after the knock begins, since their complete destruction will lead to the fact that movement is impossible, the torque will not be distributed;
• steering system, tips and rods - they should also be changed as soon as you find problems, since the lack of a replacement will expose you to danger;
• the braking system does not tolerate any delays, so it is worth repairing and restoring it immediately after diagnosing and detecting any breakdowns;
• rear suspension parts can usually wait, but if it does not involve wheel bearings, these parts should be changed in time to avoid various troubles.

Checking the operation of a wheel bearing is incredibly simple - you just need to accelerate to a speed of 90 kilometers per hour and try to hear the hum from the front and rear suspension. If there is a hum, you can safely change the bearing on a certain side. If there is no hum, nothing needs to be changed. You can also jack up the wheel and try to spin it as much as possible to get information about the bearings and their condition.

What is impossible to diagnose on your own in the suspension?

There are car suspension parts that cannot be diagnosed on your own. Often, even with a detailed examination of each element, it is very difficult to find the necessary problems. This does not mean that you can continue to operate the car without paying attention to the knock. It is especially worth contacting the service, if the knock intensifies, its appearance becomes more frequent. In this case, the following details may be to blame:

• directly the racks that are out of order, it is almost impossible to check this, except that during a visual inspection you will see leaking oil on the racks;
• ball joint - it is simply impossible to check it during a visual inspection of the machine, so you have to check it already when disassembling the parts of the chassis;
• the brake system, which is hidden far enough from the driver’s eyes and has a rather complex design, so it’s not worth repairing it yourself;
• thrust bearings - it is extremely difficult to determine what exactly they are to blame for the fact that your car knocks on bumps or when turning, this is a complex suspension part;
• stabilizers and other important suspension elements that can only be checked on bushings, it is quite difficult to check the mechanisms themselves, for this you will have to go to the service station.

At a good service, you will be given a reliable inspection of every detail, and professional conclusions will be drawn. But we are talking only about complex things that really turn out to be unpleasant for the car owner. You can use a variety of diagnostic features, but the use of the hands of a master is difficult to replace with anything else. If you find a complex problem, you should immediately fix the problem and install high-quality parts. We offer you to watch a short video with suspension diagnostics and the usual steps for this process:

Summing up

There are many unusual and rare problems that can actually be quite difficult for every car. Suspension suffers from a lot of hits on unexpected pits, from driving on an initially poor quality road. You can find a whole list of reasons for failure, among which there will be natural wear and tear. Therefore, you should not look for reasons, you just need to fix the problems that have arisen and make high-quality durable repairs. Without this, the operation of the car will be impossible, you will have to constantly drive and think that the suspension can crumble at any moment.

Particular attention should be paid to suspension parts that are out of order. At the service, you should ask to explain the reasons for such a breakdown in order to prevent such mistakes in driving a car in the future. It often turns out that the car just starts to break down, one part after another comes out. This happens when the factory-guaranteed resource of all spare parts ends. In this case, it will be necessary to repair the machine for a long and expensive time. However, after installing original high-quality spare parts, you can forget about the problem for many years. Have you ever carried out an independent diagnosis of the running gear of the car?

It is an important point not only when buying a car, but also when carrying out routine maintenance. Consider how to check the chassis of a car, determine the source of extraneous sounds, and also calculate the remaining life of some suspension elements.

Test Drive

Any test of the chassis begins in motion. Open the window to more accurately determine where extraneous sounds are coming from. Watch the behavior of the car on the road. There should be no yaw, excessive swaying on undulating sections of the roadway and roll in corners. Be sure to pay attention to the operation of the brake system.

At a speed of 20-30 km / h, turn the steering wheel in different directions. The appearance of clicks or crackling will indicate a malfunction of the CV joint or thrust bearing. With a static inspection, this malfunction cannot be detected.

To conduct a full inspection, you will need a lift and an assistant. A jack can be used to check the wheel bearings. The inconvenience is that you have to jack up each wheel. From the tool you will need: a crowbar, a mount or an ordinary piece of a strong pipe, a flashlight. Don't forget gloves.

Ground check

Ask the assistant to pull the steering wheel with sharp movements with a small amplitude. At this moment, listen for yourself to see if knocks come from the steering rack. If possible, pull the levers of the steering rack of the car. There must be no play in the vertical direction. The opposite will indicate broken bushings in the rack or a worn steering rod guide.

Steering rack malfunctions in the initial stage can only manifest themselves under certain conditions, so when you drive a new used car for you, you may not notice symptoms. Keep in mind that over time the problem will progress, resulting in the need for costly repairs.

For subsequent express diagnostics, you need:

• ask an assistant on a muffled car to turn the steering wheel in both directions until it stops. In this one, put your hand on the glass at the location of the support. If you feel, hear a crunch at the moment the steering wheel is turned, the car's swivel bearing has “ended”. You can also identify this by placing your hand on the spring. At the moment of turning the wheel, it should not “jump” or vibrate, and the turning movement itself should take place smoothly;
• turn the steering wheel all the way to either side. Inspect the boot of the CV joints. It should be free of grease and rips. Bending, in this position, you can inspect the anthers of the ball, steering tips;
• inspect the visible contour of the brake line. There should be no places of deep corrosion on the tubes, brake hoses should be free of torn;
• rock each side of the car. A serviceable shock absorber will return to dampen the oscillation in 1 movement. Otherwise, the machine by inertia will swing a few more times. Inspect the shock absorber rod for smudges and oil fogging. Such a defect indicates leakage of the stuffing box.

Lift check

Some running gear failures cannot be identified without hanging the wheels. After lifting the machine, perform the following procedures:

• rock the wheels back and forth in a vertical direction. If you find play, the wheel bearing is to blame. When driving, a malfunction is often accompanied by a hum at speed. A similar symptom may appear or disappear in turns. Spin the wheel. It should rotate without delay, rustling or crunching. Do the same movement, only in a horizontal direction. Backlash can be from a wheel bearing, steering tip or rack;
• lay the lever (mount, pipe, etc.) between the steering knuckle and the suspension arm. By applying force in the vertical and horizontal direction, it is possible to determine the presence of wear in the ball joint and steering tips of the undercarriage;
• stabilizer links should not play in the vertical and horizontal planes. Pull them with your hands or apply force with a lever. Apply force to the stabilizer link itself. If you find a significant backlash, then it is necessary to change the sealing bushings;
• one of the main elements of the chassis of the car - silent blocks. Their verification should be given the most attention. Start the inspection of rubber products by looking for tears or obvious signs of rubber delamination from metal bushings and clips. Using the lever, apply force in different planes. Elements fixed by whole silent blocks should make only small deviations, and then return to their original position again. In rocking, detachment or expansion of tears can be observed. This behavior is a clear message to repair the chassis of the car.

12.09.2016

Good day dear readers of the site Autoavenue, today I will tell you how to check the suspension of a car yourself, and understand what parts need to be repaired or replaced.

In order to start diagnosing, you will need a garage with a pit, a lift or a flyover. The goal is to be able to inspect the car from below. It will also not be superfluous to get gloves, a crowbar or a crowbar. If this is the first time you see your car in this perspective, do not be afraid, despite the apparent complexity of the suspension device, it consists of typical elements.

Let's look at the most unreliable of them:

• Ball bearings - used at the points of movable T-shaped joints.
• Silent blocks and bushings are rubber bands inserted into bolted joints to dampen vibration and noise.
• Anthers are such rubber covers that cover the nodes from dust, water and dirt.
• Stabilizer struts - consist of steering knuckles, and serve as a connector for the ends of the stabilizer with the main suspension element
• Oil seals are rubber rings that are installed in assemblies to retain oil in the place where the shafts or moving parts rotate.
• Bearings, springs, and suspension struts.

Recommendations on how to check the suspension of the car yourself.

The diagnostic procedure is standard and quite simple, but let's talk about everything in order:

1. To begin with, conduct a visual inspection, the left and right parts of the suspension are assembled symmetrically, so when comparing them, pay attention to whether all the details and fasteners are in place. If something is missing, then driving such a car is very dangerous.
2. Shake the hung wheels in the vertical and horizontal planes, there should not be any knocks and backlashes, if they are present, check whether the hub nut is well tightened. Then firmly grasp the wheel with both hands and slowly begin to turn it, while slightly rocking. This is how the wheel bearing is checked for wear, if there is even the smallest backlash, or rotation occurs with wedging, the bearing needs to be replaced.
3. Inspect absolutely all the anthers of the front and rear suspension, they should be intact and elastic, if you see cracks or tears, then such anther needs to be replaced as soon as possible (if this is not done, quite expensive components, such as an inner or outer CV joint, will need to be replaced soon etc.).
4. Necessarily check the brake hoses, no cracks or leaks are allowed if these defects have been identified, urgent replacement of failed elements is required. Brakes do not forgive slovenliness.
5. Pick up a pre-prepared crowbar or mount, and use them to check the ball joints. A bit of theory- the working part of the ball consists of a body, a pin and plastic liners, it is the plastic insert that wears out during operation. Your task, using multidirectional efforts, is to understand whether there is wear or not. To check, you do not need to apply a lot of effort, and during the wiggle there should not be any backlashes and knocks, if backlashes are present, the ball joint must be replaced.
6. The next objects of our close attention are silent blocks and bushings, if they are not in order, then when driving through bumps, sharp acceleration or engine braking, a thud will be heard. Checking them is quite simple, first inspect them visually for cracks and gusts, they should not be. Then we insert the assembly into the connection and carefully try to push the silent block. The new silent block is quite difficult to squeeze.
7. Now we evaluate the condition of the oil seals, they are installed in the main units of the car. For example, in an engine, gearbox, gearbox or steering rack, and are responsible for keeping lubricants at the exit points of rotating or moving parts. If you see traces of oil leakage from the unit or its fogging in the places where the oil seal is installed, it must be replaced.
8. Finally, inspect the shock absorbers and springs. The springs must be whole and equal in the number of turns on the left and right, and the racks must have whole anthers and no traces of oil leakage. If their condition is suspicious, then you should be checked at a car service at a specialized stand, or show the car to a qualified mechanic. Be aware that worn shock absorbers can cause a serious accident when maneuvering or braking hard on rough roads.

   

Summarize:

Try to do suspension diagnostics every six months when preparing the car for the winter and summer seasons. This will not only identify and eliminate breakdowns in the early stages, but will make traveling by car safer and more comfortable for you and your passengers.

Suspension Diagnostics(front) consists in checking the transmission and steering, which consist of the following components, which are most often subject to failure:

1. Shock absorbers;
2. Springs;
3. Ball joints;
4. Lower arms with silent blocks;
5. Upper suspension mounts with bearings;
6. Stabilizer rods;
7. Stabilizer supports;
8. Steering rack;
9. Tie rods;
10. Steering tips;
11. Steering cardan;
12. Hub bearing;
13. SHRUS (external hinge).

Before you get busy suspension diagnostics, all rubber boots and anthers of the listed parts should be inspected. As a rule, a part that has a damaged cover needs to be replaced.
A serviceable shock absorber should not have oil smudges, its rod should have a smooth mirror surface without shells and scratches, it should not make sounds when the car is rocking, and almost immediately dampen the vibrations of the car. When driving with a faulty shock absorber, the car sways, and from the side it seems that the wheel does not roll along the road, but jumps like a ball. Oil leaks occur before other symptoms and with them the shock absorber can still work normally for a while.

Worn (sagging) springs are identified by the low landing of the machine and the inability to properly adjust the camber.

Ball joints are checked by swinging the lower arms up and down using a mount on a pit or lift. In this case, there should not be a noticeable backlash.

Silent blocks of the lower levers should not have play when pressed with a mount, should not have bulging and cracked pieces of rubber, rubber should not peel off from the inner or outer bushings.

Includes check of ball joints and silent blocks, which need to be looked at on a raised car, unscrew the fastening of the ball joint to the lower arm. After that, when turning the body of the ball joint by hand, it should move smoothly, with effort and without backlash. The lower arm in the free position should tend to take a horizontal position, under the action of the elasticity of the rubber of the silent blocks.
Faulty upper suspension bearings may have play when the machine is rocked up and down. In addition, the rubber part can be torn in the support, but it is not always possible to identify this without removing the support.

The stabilizer links and supports are checked by inspection and swinging by hand with effort. All joints should not have any backlash.

The steering rack very rarely fails, except when the guide bush on the side opposite to the driver wears out. This can be determined by swinging the rail itself with your hands, turning the wheels in the direction of the steering wheel, holding the rail through the tie rod cover.

Tie rods and steering tips are checked either by turning the wheel with your hands, or by turning the steering wheel left and right, while holding the part being checked with your hand. Neither rods nor tips should have any play.

A faulty steering cardan can either have a backlash, sometimes quite large, or vice versa - turn with effort. If on your car the steering cardan shaft does not have any cover or cover, it is recommended to pick up and put some kind of cover on it. Steering rod covers are well suited, you can also pick up a cover from a domestic car.

A faulty one can make a hum when driving, which is checked by spinning the wheels on a well-fixed posted car. It can also have a backlash, which is checked by swinging the wheel with your hands at its upper point from yourself to yourself.

A faulty external CV joint produces a characteristic loud crack when the car is moving with a slight acceleration in a sharp turn.

The front suspension may have other malfunctions, only the most typical ones are described here, so the full suspension diagnostics it is better to carry out at specialized car service stations