In conditions of poor road conditions, suspension parts become a weak part. The main ones are shock absorbers and springs. Let's discuss the question: do I need to change the springs when replacing shock absorbers.
What are they for?
Shock absorber and spring always work in pairs, performing two parts of one task - ensuring the smoothness of the ride and controllability of the machine. A spring is an elastic suspension element that softens shocks and shocks from driving on rough roads. After hitting an obstacle, the wheel lifts off the ground and becomes uncontrollable.The task of the spring is to return it to its place as soon as possible, but after hitting the road, the wheel bounces back, and the softer the spring, the more it can compress and absorb more energy. Because this energy is consumed very slowly, then the vibrations will not fade for a long time, being fed by new shocks from bumps in the road. To solve this problem, a shock absorber comes to the rescue, which is designed to quickly dampen wheel vibrations by converting body and suspension rocking into heat.
Due to its complexity, the shock absorber is a less reliable device that requires periodic replacement when the quality of work deteriorates.
What needs to be changed in the suspension?
Normal operation of the suspension is possible only with the correct interaction and full performance of their functions by the shock absorber and spring. While the springs hold the weight of the machine, their movements are controlled by shock absorbers - respectively they depend on each other. If any of the components “does not finish”, then he shifts part of the work to the “partner”. If the spring sags, then overloaded extra work the shock absorber fails much faster, and a bad shock absorber cannot properly restrict the movement of the spring and rock the car.The condition of the spring also determines the holding of the road, and the degree of negative effect on the shock absorbers and tips, and the braking performance of the car. But why does the spring lose its properties? This is due to:
- Metal fatigue depending on natural wear;
- Surface damage (friction, stones, full compression);
- Frequent overloading of the car or overcoming uneven sections of the road at speed;
- Corrosion of metal (high humidity, influence of road salt).
It is most optimal when replacing shock absorbers to also change the springs, but this is expensive and not so necessary, given that it is visually impossible to determine some characteristics of the springs, for example, the degree of metal fatigue.
Installing new shock absorbers in combination with old and rusting springs is a suspension repair by half while shortening the life of all suspension components. With the simultaneous replacement of all parts, the suspension will be restored to original condition. As an added bonus, part of the cost will be returned due to savings on double payment for work.
The choice is yours, but springs ALWAYS change when:
- Their breakage (usually they break in the uppermost or lower turns);
- Visible corrosion or metal damage;
- Reducing the height of the machine (it is necessary to measure and compare the distance between the center of the wheel and the edge of the wheel arch on all four wheels);
- The difference in height between the front and rear of the car.
It must be recalled that, like shock absorbers, springs are changed in pairs per axle, otherwise, due to their different condition, suspension imbalance will occur, which will affect handling.
It's no secret that the quality of domestic roads leaves much to be desired, so the serviceability and proper adjustment of all elements car suspension- an important factor in comfortable movement. One of the main components of the suspension are springs, which provide the necessary height of the body above the roadway, and also affect the load capacity and handling of the machine. The optimum stiffness level of these elements is determined by testing under various driving conditions, and the ideal spring force is equal to the value that prevents excessive body roll.
If the springs are chosen correctly, then at any turns the body roll should be no more than two or three degrees, which is paid special attention to. Too soft springs can significantly affect the handling of the car. But how do you know the spring rate of your vehicle? This is exactly what will be discussed in this article.
1. How to determine the stiffness of the suspension spring?
First, let's remember what a car spring is and what it is. This component of the suspension design is presented in the form of an elastic element that softens shocks and shocks that occur when moving along uneven sections of the road, because when hitting an obstacle, the wheel of the car breaks away from the surface and loses controllability. In such cases, the task of the spring is to return it to its previous position as quickly as possible. Given that the wheel bounces back after impact, a soft spring is able to compress more and absorb more energy than a hard element. Since this energy is spent slowly, the oscillations cannot quickly die out, being fed by more and more new shocks.
Another one to solve this problem structural element automotive - a shock absorber designed to accelerate the process of damping shocks by transforming suspension and body vibrations into heat.
The stiffness of a spring is its ability to resist compression, which is also its main characteristic. A spring that is too stiff reduces the quality of the car's handling on rough roads, while increasing passenger discomfort. Too soft, on the contrary, dampens shocks well, but creates a large roll of the car when cornering. There are several factors that directly affect the stiffness index:
1. Rod diameter(the larger it is, the greater will be the rigidity);
2. External diameter of the spring(the larger it is, the lower the stiffness index will be);
3. Number of coils of the spring(more turns - less rigidity);
4. The shape of the spring. There are cylindrical, conical, barrel-shaped elements, each of which may have special characteristics. In addition, one spring is able to combine several forms at once.
You can determine the stiffness of the springs installed on your car based on the product code or applied marks in the form of stampings or paint markings (for example, the length of the spring is at least 230 mm, and if the product is marked with a yellow marking, then it has a length of less than 240 mm). Also, a hand press, floor scales and a measuring ruler will help you find out the stiffness value (pressure force is measured in kilograms per centimeter).
To do this, put on the scales wooden block not less than 12 mm thick, the area of \u200b\u200bwhich will be greater than the area of \u200b\u200bthe end of the spring, and the spring itself is installed on top of it. The upper end of the spring is covered with a second block of wood and the length of the element is measured. Using a press, the spring is compressed to a specific value (for example, 40 mm) and the readings of the scales are recorded, thereby determining the stiffness of the part.
There is another way to determine the specified value. Here, the suspension spring is considered as a body of initial length, denoted by the letter "L" and subjected to tension or compression. In accordance with Hooke's law for longitudinal deformation, changes in the body "x" are proportional to its initial length "L" and the applied force "F". I.e, x = F*L/C, where "C" is a proportionality factor and depends on the radius of the coils, the diameter of the wire and the material of the spring. Spring rate- k \u003d F / x \u003d C / L or k * L \u003d C (“C” is a constant value).
2. How to properly check suspension springs
Often, attention is paid to suspension elements only when something knocks somewhere or the car starts to behave inappropriately. However, any problem is easier to solve at the initial stage than to suffer with its consequences. In the case of suspension springs, the following signs may indicate their poor “well-being”:
1. Frequent "breakdowns" of the suspension;
2. Reduced ride vehicle;
3. The appearance of vibration and shaking during movement;
4. Noticeable skew of the car or its draft;
5. Significant difference between the height of the front and rear of the machine;
6. Reducing ground clearance;
7. Pronounced traces of the interaction of spring coils (visible during diagnostic procedures on a viewing hole or on a lift).
Why can a spring lose its former properties? Firstly, makes itself felt by the natural wear and tear of the metal. Secondly damage to the springs due to friction, full compression or contact with stones cannot be ruled out. IN -third, frequent overloads of the vehicle and overcoming uneven sections of the road at high speeds can lead to spring failures, and metal corrosion due to an increased level of humidity and the influence of road reagents completes the “dirty work”.
If during inspection you notice damage to the coils of at least one of the springs, such a part must be replaced with a new element. It is also useful to check the settling of the springs. To do this, the part is compressed until the turns come into contact, after which a load of 295 kgf is applied. The spring is compressed along its axis, and the supporting surface must correspond to the support cup of the shock absorber and the body.
In addition, when performing diagnostics, pay attention to the condition of the spring gaskets: if signs of wear are clearly visible on them, it is better to replace such elements immediately. With minor defects, you can not change the spring yet, but it is imperative to replace it if:
- the part is broken (usually this happens in the upper or lower turns);
Strongly noticeable corrosion or other damage to the metal;
The height of the car has decreased (the distance between the center of the wheel and the edge of its arch is measured and compared, and on all four wheels);
There is an uneven vehicle horizon (difference in height between the front and rear of the car).
3. Suspension spring test tools
For complete diagnosis suspension springs, you will need both ordinary tools (wrenches and socket wrenches, screwdrivers, a hammer, etc.), as well as special spring pullers and couplers. As for the latter, they greatly facilitate the task of dismantling, however, many motorists can do just fine without them. If you are going to check the stiffness of the springs, then the floor scales mentioned earlier, a measuring tape, a hand press and wooden blocks of a suitable size will not be superfluous.
The content of the article:
Mercedes-Benz S-class WITH SPRINGS Yekaterinburg, Russia. Nikonov Springs for Mercedes W A couple of sets went to Minsk. 98 year S hp Stands on the springs, who needs hemorrhoids with pneuma can put it.
Forum of the official Mercedes club in Russia - Mercedes-Benz Club Russia. I, like many of you, thought and did not suspect that a complete set with springs at the back was used for the r-ku. I had air bellows only at the back.
On a Mercedes, springs are generally removed in a completely different way. The puller is slipped from below through the lever, and a plate is inserted into the coils. A pair of non-original springs costs 80 ue, so your hundred and podrebanil.
It was decided to definitely change to springs, especially since it turned out to be not a "collective farm", but in the EPC there is a configuration option with springs. There is gas equipment, since I ride a lot at work and in the trunk there is a 90-liter cylinder. Engines, transmissions, fuel systems. Why are we worse than "engineers" from ARNOT or others. Your rights are in the section.
Why are we worse than "engineers" from ARNOT or others. I took the factory type from Omsk. But the back is generally tough. On small pits it shakes specifically. How do you walk. I'm planning on redoing it in the next few days. Pls tell me what should be the total length rear pillar m, see? ATP And from which car springs and shock absorber? What did the Mercedes sell? It's a shame listen - I put my hands on it, rear suspension corrected. Cool to this model? You had a bmwuha. Even stupid - how can you take a puzoter temporarily instead of a jeep, if you already have a puzoter.
There are such roofing felts resistors roofing felts diodes that you need to cling to the wires and they give resistance that the computer understands how - everything is fine. This electrician must be connected to a normal one. Toyota Chaser BLUE Rogue. Previously, engine compression Shaking from the springs. Either cut or put soft. Maybe there are some finalization drawings that the locksmith needs to do? Reply to a deleted comment by Kabard 11 months ago. Same as native. What car are the springs and dampers from? It was a temporary option before purchasing an SUV.
It is welded to it from Honda SRV cut in place. From the soul of a brother, from the soul to the soul.
It's no secret that the suspension experiences serious "shocks" due to the quality of the roads. And in order to somehow minimize the impact, springs are installed. They affect not only the main parameter, like the height of the body above the ground, but also allow you to keep the car at a practically given height, even taking into account the cargo taken on board. In addition, there is an opinion that the effect of springs on the suspension as a whole is favorable, and the handling of the car improves.
Remember that the device of all springs is generally identical, the only differences that can be are the stiffness index and the type of the products themselves in shape.
Keep in mind that depending on the type of part, roll in corners may exceed the allowable 3-4 degrees. For properly selected springs, this indicator is kept at a level of no more than two degrees. Therefore, it is very important to choose the right element that will correspond not only to the nature of your driving, but also to the basic requirements of the manufacturer for a particular model.
Also, keep in mind that part of choosing the right spring depends on where it is installed. After all, there are two options for placement - on the counter and separately.
Spring in
For example, often when the location of the shock absorber and spring are separate, barrel-shaped and conical shapes are chosen.
But, for installation on racks, preference is given to coil springs. The true reason for this "policy" of the manufacturers is not known, but there is an opinion that this format is due to the fact that the racks are usually installed at right angles. And when the location is separate, a small angle is provided, and in this case, the cone and the “barrel” allow you to “eliminate” the stress when the spring “plays” on bumps and sags due to overload.
In general, one can notice such a pattern when a joint pair of racks and a spring is installed, the main emphasis is on stiffness and clearance. But, it must also be borne in mind that stiffer springs can also be used. Regarding the separate location, the shock absorption occurs along several trajectories, depending on the modification. From which, many assure that the separate type is more adapted to driving on bumpy roads and the city, it is comfortable in the cabin, because in this case, the suspension works out multidirectional impacts better.
Rigidity, how to determine?
First, let's fix what is a spring? This is an obligatory component of the suspension, which is presented as a certain elastic element. It provides mitigation of shocks, shocks, including during sudden braking and starts. The purpose of the spring is to return the wheel to its original “position” as quickly as possible after hitting an obstacle.
A part that is too rigid significantly impairs the vehicle's handling, especially on rough roads. However, the advantage of increased rigidity is greater safety when driving at high speeds. That is, it does not allow the body to sway as much as a too soft one. The latter cope with almost all pits without discomfort for the driver, but it is difficult to enter turns with such springs.
Remember, there are several main factors that affect stiffness. Knowing them, you can independently determine the type of your own element installed on the suspension. So:
1. The diameter of the rod itself. Remember an important pattern, the thicker the rod, the more rigid the part.
2. Diameter of the spring on the outside. The larger the diameter, the lower the actual stiffness.
3. Form. There are several basic types: conical, cylindrical, "barrel-shaped". Each variety has its own characteristics and characteristics. There are also combined.
4. Number of turns. The pattern is this - the more turns, the less rigidity will be.
Hardness is determined quite simply. In most cases, the manufacturer independently applies the marking, which makes it clear which class the product belongs to.
Remember that the marking in yellow indicates a length of up to 240 mm. But, basically, all the indicators that are required to calculate the stiffness are on the product.
If no marking was found, the indicator can be calculated as follows. So, prepare scales (ordinary floor scales), a wooden block, a ruler, the product itself. You need to lay the block on the scales, but remember that the width of the board must be greater than the diameter of the spring. Next, we take the second board and press it from above and measure the length of the product, of course, without taking into account the boards. Independently or using a special press, the spring must be compressed to a certain level. As a rule, it is 40 mm. Record information from the scales. Further, having the initial length in the expanded position and compressed, we calculate the difference. Further, it is necessary to divide the resulting weight after compression by the difference, thereby obtaining an indicator of rigidity.
There are more complex methods of calculation, but it’s not worth talking about them, because at least two more values \u200b\u200bare required, which you can derive using Hooke’s formulas and laws, as well as the theory of proportionality. For an ordinary driver, this method of calculation is superfluous, it is much easier to find out.
Resource, and which is better to choose?
As a rule, among the most popular queries in search engines, what is the “mileage” of the springs, and which ones are better to choose? It is difficult to judge which is better, because each motorist has his own preferences in this regard. Someone likes fast driving and for him the rigidity of safety requirements, someone prefers comfort. Everything is individual, moreover, today there are a huge number of manufacturers who can offer universal springs, including the so-called adjustable ones.
What is meant by the word regulated? It just seems to you that everything is simple, but they can still differ from each other. There are two types:
With an adjustable "nut", which is screwed onto the cylinder and allows you to both increase and decrease the stiffness depending on the "winding".
With an adjustable spacer, in principle, many of these two points do not even share
What is the resource? It is difficult to answer affirmatively about the service life, because everything depends on the quality of the roads directly. Somewhere the springs serve even 100,000 km, but somewhere they don’t “pass” even 10,000 km. In general, it can be noted that the greater the rigidity, the more durable, and vice versa. The average "mileage" rarely exceeds 50,000 km.
Faults and their symptoms
As such, there are not so many malfunctions; in fact, the constructive part of this element is not difficult. They share the following types of problems:
Breakage of the bar at the edges.
Trite "tired" metal.
Broken coil.
In general, that's all, there is nothing more to add. Either the spring sank, due to frequent overloads, or the coil burst, that's all.
What are the symptoms of failure? Here you can see a wide range of signs:
2. Appearance or knocking.
3. Valkost car. That is, the situation when, when braking and starting, the car “pecks”.
4. "Breakthroughs" of the suspension. When, when hitting bumps, pits, “humps”, metal elements touch, for example, turns between themselves. In serviceable products, this should not be the case.
5. Large rolls in corners.
6. Discrepancy in the height of the limber and stern.
The reasons for this are varied.:
Wear due to old age.
Improper operation (transportation of large loads).
Reagents and chemistry in general.