Huge variety oil mixtures produced for automotive engines, allows motorists to choose the product that they subjectively like the most. These include motor oil with molybdenum, the exceptional qualities of which many have heard. With this additive, oily liquids of the German trade are traditionally produced. brands Liqui Moly. As a rule, every medal has two sides. Therefore, let's try to figure out whether there are negative effects in the use of molybdenum disulfide, in addition to positive ones.

History of appearance

The use of molybdenum disulfide for engines internal combustion began in the United States at the end of World War II. Initially, this substance, in addition to metallurgy, was used in aviation. Molybdenum is not found as a pure metal. But a compound such as the mineral MoS2 (molybdenite) is quite common. The Americans noted its anti-friction and anti-corrosion qualities, resistance to high temperatures and good viscosity. Experiments on the use of this compound as a dispersed additive to aviation oils showed amazing results.

Thanks to the lubricating properties of molybdenum disulfide, the aircraft engine could run without lubrication - though not for long. This was a kind of reinsurance - in case the oil lines or the crankcase were damaged. Then the pilot could reach suitable place where the plane could land.

The idea to use this powder for other purposes came to the German Hans Henle when he discovered Liqui Moly jars with powdered molybdenum (translated as “liquid molybdenum”). After learning what they were used for, Hans decided to use molybdenite for motor oils. The results exceeded all expectations. In 1955, he bought a patent for the use of molybdenum disulfide and the rights to this trademark, and by 1997 founded Liqui Moly GmbH.

At first, molybdenum additives were sold for oils of the Kfz series, intended for both motor oils and transmissions. Motor lubricants, which included MoS2, began to be produced only in the late 70s, after sensational promotions liquid moly additives. Two small VW-Kaefer cars circled the Bodensee lake, having only molybdenum additive instead of oil inside their engines. This created a sensation and caused a real boom in molybdenum disulfide.

Main properties of MoS2

In scientific terms, molybdenum disulfide is a friction modifier. This is one of the main additives that make up any engine oil. Only for it different substances and their compounds are used - for example, manufacturers use graphite. MoS2 is similar to it in many of its qualities. His molecular structure, being lamellar, like graphite, consists of molybdenum and sulfur atoms, forming a very strong compound.

Good protective, anti-friction and extreme pressure qualities appear due to the fact that the atoms of molybdenum and sulfur are approximately the same in size. Thus, a uniform crystal lattice is formed. When added to motor lubricants, molybdenum disulfide creates a strong film at the points of contact of parts that can withstand very high pressure without breaking. MoS2 molecules are highly mobile with respect to each other. Therefore, the friction between the contacting parts is sharply reduced.

Molybdenum compounds perform well at high temperatures (300–400°C) that accompany work piston group. Other compounds, as a rule, lose their basic qualities under such temperature conditions.

In addition to the clearly positive effect, this friction modifier also has disadvantages: for example, the inability to dissolve in oily liquid. That is, the state of the powder can be called dispersed, which is a suspension consisting of fairly large particles. Therefore, oils with molybdenum do not behave well in all engines. Be wary of its use in powerful engines developing very high temperatures inside the cylinders. As a result, deposits are formed and power units are coked, although such information has not been officially confirmed. It may well be that the reason for the formation of slags was different: calcium contained in other additives, especially detergents, actively affects MoS2, leveling all of its good qualities. This process is facilitated by high temperature conditions. Therefore, there are recommendations to treat molybdenum-containing lubricants with caution.

Liqui Moly range of oils

Today German company produces a wide range of motor oils - from high-quality mineral to fully synthetic, called HighTech-Oel. The products have different price categories. Molybdenum is present in motor oils as a friction modifier. If molybdenite had a negative effect on some powertrains, probably, the oils would not have been certified according to the API (American Petroleum Institute) classifier as energy conserving (energy conserving, EC), as well as ACEA ( European Association car manufacturers).

Use of oils German manufacturer allows you to save from 1.5 to 2% of fuel. One of legendary brands, which brought an army of fans and the recognition of molybdenite - MoS2 Leichtlauf SAE 10W-40 engine oil. This is a semi-synthetic product, based on 40% real synthesized synthetics based on polyalphaolefins (PAO). The remaining 60% is a high-quality purified mineral composition. In addition to MoS2, the composition of the lubricant contains additional anti-wear additives.

Thus, two layers are formed between the rubbing surfaces at once. When one of them stops working due to exhaustion, molybdenite takes its place. It has such a fine structure that it does not linger oil filters while remaining in balance. Thanks to him lubricant composition retains its basic anti-wear properties throughout the entire interval between replacements. The API classifier assigned the product SL / CF values, ACEA defined its categories as A3-04 / B4-04. The lubricant is suitable for both gasoline units as well as for diesels.

Fully synthetic energy-saving lubricants include Special Tec Aa 5w-30. This is a modern lubricant composition that can be used with a replacement interval of up to 40 thousand kilometers! He was awarded the highest category API classifiers, as well as ILSAC - SN / CF and GF-5, respectively. The product has many official approvals from European and Asian car manufacturers:

There are very few products in the world with such an impressive list of tolerances. All this speaks of great performance characteristics this engine oil.

There are quite a few motor oils with molybdenum on the market today. Moreover, the amount of this component, its molecular structure and mechanism of action can be quite different.

On the Internet and among motorists, disputes still do not subside about how justified the use of molybdenum in engine oil is. Indeed, often lubricants with this chemical element are more expensive.

Let's try to figure out what molybdenum disulfide is in a lubricant - is it good or bad? We will also find out how this component helps lubricants protect the engine and whether it is worth paying attention to oils with molybdenum-containing additives.

Brief history of discovery

What is molybdenum? AT pure form is it metal powder or lumpy metal gray color with a low coefficient of friction and thermal expansion, high melting and boiling points.

However, in its pure form, this metal is of little value in the motor oil industry. Much more interesting are some of its compounds with other chemical components.

Molybdenum Disulfide Powder

The unique properties of molybdenum disulfide (MoS2) were known as early as the middle of the 20th century. For the first time, documentary evidence of the real use of this chemical element outside of laboratory conditions refers to the military industry. In the 1950s, Americans added molybdenum additives to oils used for tank engines and military aircraft.

It was noticed that if the engine lubrication system was damaged and oil leaked, the equipment could work much longer “dry” until complete failure in the presence of molybdenum in the oil. This gave the tank a chance to leave the combat zone for repairs or the aircraft to fly to the airfield.

Later, oils with molybdenum began to be used in civil engineering. One of highlights in the history of molybdenum-containing oils is the case with the founding of Liqui Moly.

In 1957, an enterprising German drew attention to a small vial of a strange liquid that was being sold in the part of Germany controlled by the Western Allies.

It was molybdenum disulfide used in military aircraft. The German, whose name was Hans Henle, bought the rights to use this composition and began to develop motor oils under the Liqui Moly brand.

MoS2 lubricants are not uncommon today. Molybdenum-based additives are used by many manufacturers of motor and transmission lubricants.

And technology has come a long way in the last few years. And these oils today are much more technologically advanced than they were before, and are devoid of many of the shortcomings of the first versions of molybdenum-containing additives.

How molybdenum disulfide works

The MoS2 molecule, as is clear from the formula, consists of one molybdenum atom and two sulfur atoms. Easily combines into a film with a thickness of one molecule. Attracted to metal surfaces.

Crystal lattice of MoS2 film

Due to these qualities, molybdenum disulphide quickly spreads over the metal surfaces inside the engine and forms a thin surface layer. The film formed during the mutual displacement of the layers relative to each other has a very low coefficient of friction. At the same time, the strength of the film itself and its adhesion to metal surfaces is very high.

In the event of shock loading or thermal decomposition, the damaged area is filled within a short time with free molecules of molybdenum disulphide present in the oil volume.

Advantages and disadvantages

Like any additive, pure molybdenum disulfide has pros and cons. Consider first the benefits of using molybdenum additives in modern motor oils.

1. Reducing the coefficient of friction in mates. This is one of the most significant and determining the popularity of car oils with molybdenum properties. Low odds friction increases Engine efficiency, increases its power and throttle response, reduces fuel consumption.
2. Increase protective properties rubbing surfaces. Protective film protects metal surfaces from dry friction during mechanical load fluctuations.
3. Rapid formation on metal surfaces and the ability to restore the integrity of the film in case of damage.

Influence of the amount of triatomic molybdenum on the coefficient of friction

Today, oils with molybdenum disulfide in its pure form are practically not produced. And there are several negative reasons for this.

1. Molybdenum disulfide in its pure form begins to form molecular bonds even before contact with metal surfaces. This leads to the formation of coarse particles, which have a density higher than that of the oil. If the engine is idle, molybdenum particles settle to the bottom of the sump and do not participate in operation for some time after the engine is started.
2. After pouring new oil, molybdenum forms a protective film on all metal surfaces. The remaining molecules circulate freely in the volume of the lubricating fluid. Being a compound that is not the most stable, molybdenum disulfide gradually decomposes into non-functional compounds and can no longer participate in the protection of engine parts.
3. In some cases, an excess of molybdenum disulfide does not work for the benefit, but harms the engine. To increase the service life, manufacturers increase the concentration of this component in the oil. Some of the molecules bind on metal surfaces to form a film. The rest circulates through the system and settles in the form of clots in the most inconvenient places: in the gaps piston rings, on sensors, in the bends of oil lines. Often these precipitations lead to unpleasant problems.

Features of the work of molybdenum additives in modern oils

Most modern motor oils do not use molybdenum disulfide in its pure form. The effectiveness of lubricants using additives based on pure MoS2 has shown to be inefficient and uncompetitive.

Modern oils are not considered in terms of individual modifiers used to improve performance. Additive manufacturers primarily make formulations that have complex characteristics, and do not focus on individual components.

Under these conditions, the use of molybdenum required the development of new methods for the delivery and introduction of this component. And such a solution was found in the use of a complex complex based on diatomic (Mo-DTC and Mo-DTP) and triatomic molybdenum organic components in conjunction with a zinc modifier (Zn-DTTP).

Molybdenum is added to oil as a complex molecule that is quite resistant to breakdown. However, under the influence of the zinc component, temperature and some other factors, complex molybdenum compounds gradually decompose to the familiar MoS2. Moreover, this reaction in time is quite predictable and lends itself well to calculations.

It turns out that the addition of molybdenum dioxide is carried out in portions. Such a mechanism allows you to throw in small portions of active molybdenum throughout the entire life of the engine oil and fill in the gaps on the exposed friction surfaces. Also, this technology minimizes the negative effects of the use of molybdenum-containing oils.

Diatomic and triatomic molybdenum in interaction with zinc additives under a microscope

Therefore, today the use of modern molybdenum-containing lubricants manufactured using the latest technologies is more than justified. But before using them, you need to carefully read the operating instructions for the car. For some engine modifications, the use of such oils is contraindicated.

Motor oils with molybdenum

Despite all the disadvantages, the advantages generally prevail. And today on the market you can find many brands of motor oils with molybdenum. Let's briefly consider not individual oils, but some manufacturing companies that use additives with this component.

A visual test of the work of molybdenum in Mannol engine oil - video

• . Perhaps the most well-known firm, which uses molybdenum-containing additives in its products. It was on this component that the entire marketing system was built at one time, which allowed the company to become world famous almost from scratch in a few years.
• Mannol. Inexpensive motor oils that use molybdenum.
• Exxon Mobil. Uses molybdenum in some of his oils. In general, these lubricants are known for their innovative approach and the search for new solutions.
• Idemitsu. These lubricants use organic molybdenum compounds, which are the most stable.

To one degree or another, molybdenum-containing additives were used by many manufacturers of motor oils. Now this technology is in limbo. Many actively develop and promote it. Others, on the contrary, abandoned the prospect of using this component in their products.

Molybdenum additive for the motor causes controversy among motorists. Someone believes that molybdenum disulfide has some advantages, it improves the functioning of the engine. Other drivers believe that this additive reduces operational period power unit.

So how do the molybdenum additives that are added to motor oil actually work?

Pluses of an additive

The requirements for emissions into the atmosphere and fuel consumption are getting tougher. They refer to manufacturers of both motor oils and cars. To restore antifriction layers in areas with a broken lubricating film, molybdenum disulfide is used, which has the following properties:

• minimizes the number of scoring in the engine;
• improves engine lubrication;
• reduces wear.

Seizures in the engine cylinder

These additives are present in many lubricants manufactured today. Organic molybdenum interacts well with sulfur. This gives him the opportunity to securely attach to the piston or other moving part that requires high-quality lubrication.

Molybdenum-based oil additives are known to reduce the friction of contacting parts. As a result, engine wear is significantly reduced. You need to repair the engine much less frequently.

The effect of molybdenum disulfide

Molybdenum additive does not deposit on motor parts. It forms a thin film that does not overfill the gaps, does not interfere with the circulation of the lubricant. The film is formed only if you regularly use, for example, the additive Liquid Moli with molybdenum. When a motorist stops using the powder and starts pouring ordinary car oil, the film is subject to wear. Because of this, the number of scuffs and wear of the motor increases.

Issued today motor lubricants good resistance to scuffing and wear. Thanks to automotive additives Liqui Moly, "Hado", "Mannol" can be formed repeated anti-shock layers.

Liquid moth additive

Except ordinary drivers, Liqui Moly additives are used:

• in production carried out in high temperature conditions;
• for lubrication of various materials;
• to increase the density of plastic substances.

Cons additives

According to the results of many studies, Liqui Moly additive can be effectively used in production units. If the engine is often run on high revs molybdenum particles can penetrate the piston rings.

With constant operation in high temperature conditions, combustion products settle on the pistons. The engine starts to function differently than before. Gas gusts appear, the thermal load increases and, consequently, the number of deposits. In view of this, some car manufacturers do not recommend the use of additives. What if the motorist wants to reduce friction in the engine?

You can use complex ether synthetics, which are similar in physical characteristics to castor oil. What is it for and what does it give? Its use increases adhesion, improves lubrication by forming a thin and durable film. The main advantage of lubricants containing ester synthetics is thermal stability. It is worth mentioning that in order to increase the operating period of motors military equipment molybdenum additives are often used.

Carbon deposits from oil and additives

Today, oils contain a considerable amount of calcium. It does not allow molybdenum particles to settle on the surface of the parts, as a result, large molecules appear that collect on the oil filter. The loss of calcium elements is one of the causes of contamination of the power unit. In view of this, if a motorist wishes to use a molybdenum additive, he must fill the engine with an oil product with an increased calcium content. Unfortunately, such vehicles do not yet exist.

If you "give" your motor a molybdenum additive, do not forget to change the lubricant in a timely manner. It will not work for a long time on an old car oil. The characteristics of the oil when using an additive are greatly reduced. If moisture gets into the engine, metal parts will quickly wear out and become significantly deformed.

Tribological means

According to the manufacturers of tribological products, their products are not considered an additive. They act by creating a friction-lubrication pair. A molecular lubricating layer is formed, which prevents wear of working motor parts. These funds "give" the engine along with the lubricating fluid.

When a film is formed, the following happens:

• abrasive particles that are in the tribological tool clean the motor;
• a protective layer is formed;
• changes in thickness, porosity, other physical characteristics protective layer. The hydrodynamics of the motor is improved.

Experts believe that tribological products are optimal for different engines, allow them to work in harsh conditions, with oil starvation. Also, if "give" power unit such a tool, it will work more powerfully by about ten percent.

Drivers should be aware of right rule, namely: if you do not follow the instructions attached to tribological composition, the engine may be damaged. Manufacturers also claim that such products reduce fuel costs. It is best to “give” such funds to the engines of new cars.

So why use such tools? Is it possible to do without all these disulfides and dioxides? The answer is yes, you can, as long as you use a high quality lubricating fluid. It already contains all the necessary additives that significantly improve the functioning of the engine and extend its operating period. Remember that if used incorrectly, additives can harm the motor. Therefore, carefully read the instructions that come with the additive. So you will avoid unnecessary problems associated with the operation of the power unit.

Content Molybdenum Disulfide Powder

Today, there are many positive and negative feedback motorists about the use of special additives in motor oils in which molybdenum disulfide is present. Let's try to understand what molybdenum additives are in engine oil, and what function they perform when added to lubricants.

Today, the requirements for engine manufacturers and lube oil formulaters are becoming more stringent.

The use of friction modifiers, with the help of which anti-friction layers are created in the areas of damage to the oil film, is one of the options for ensuring the presence of energy-saving qualities in engine oils.

Molybdenum disulfide is a classic antiwear and extreme pressure additive for lubricants and oils. All motor oil companies, in any case, include various anti-friction solid or liquid components in their products, such as esters, ceramics, molybdenum disulfide, graphite and others.

The principle of operation of these funds

Low soluble molybdenum additives in motor oil act on a principle similar to graphite additives and based on the lamellar layered structure of the additives. The composition of molybdenum disulfide MoS2 molecules includes one molybdenum atom, with which two sulfur atoms are firmly bound, the sizes of which can be compared with the sizes of metal atoms, which allows sulfur to be firmly fixed on the metal surfaces of rubbing parts (pistons or bearings). The connection of molybdenum with sulfur is quite strong, while the connection of sulfur particles in nearby molecules is, on the contrary, weak.

As a result of the addition of molybdenum disulfide to lubricant coating of both rubbing metal surfaces occurs protective layer, consisting of molecules of a given substance, freely sliding with respect to each other. This makes it possible to exclude direct contact between metals, significantly reduce friction and overheating of parts in areas where it is present, especially in the case of extreme loads, which significantly reduces the wear of metal parts.

Molybdenum additive

Stabilization of molybdenum disulfide occurs in motor oils quite well, which ensures the maintenance of a suspended state of the substance throughout the entire service life, preventing spontaneous settling on the surface of engines, including hydraulic compensators. The protective film of this substance has a negligible thickness compared to the operating clearances of the motor, which allows it not to maintain free circulation of oil.

Most drivers have heard more than once about various additives that help. Someone uses them regularly and recommends to others. But some people argue that most of them only harm the engine and do not bring tangible benefits. Partly it is. Low efficiency is associated primarily with the wrong addition and choice of funds. Molybdenum additives are criticized more than anyone else. What caused the heated discussion, we will understand further.

When using molybdenum additives, it is necessary to additionally clean the system.

When to use

Molybdenum additive includes active substance- molybdenum disulfide. Its protective qualities have been known to the world since the beginning of the previous century. At first, it was actively used to add to tanks. Even significant damage was not much of an obstacle in order to get to the nearest repair station. After that, the work of molybdenum was tested. The result was positive. That is why they are now widely used to increase the protection of engine parts.

A significant part of dissatisfied with the result of buyers misuses them. The molybdenum additive in the engine oil of a new engine will not show good changes. It is intended for cases when the car is operated irregularly and in small runs. Under constant load, carbon deposits remain on the surfaces of the parts. Molybdenum is also miscible with oils at high temperature. Because of this, it's much faster. To understand when to add a molybdenum additive, you need to familiarize yourself with the principle of the substance.

How molybdenum works

The principle of operation is based on the main active component - molybdenum disulfide. After the substance is stabilized in the composition of the lubricant, it does not settle on the metal surfaces of the engine. The formation of a thin film begins, covering all areas of friction and contact. The process does not last indefinitely and ends after equalizing the indicators of wear and build-up intensity. This happens due to the regular use of molybdenum additives in oil.

As soon as molybdenum stops flowing into the oil, the film begins to quickly deplete and gradually disappears completely. After that, the likelihood of scoring and bumps increases. The processes that are constantly working are also significantly accelerated, due to a sharp increase in friction. There is only one way to obtain a new molybdenum film - the next addition of an additive. Their effectiveness is not as high as compared to more modern competitors, so regular use will be an order of magnitude more expensive.

In fact, now molybdenum additives are used most often in production. This is due to the properties of disulfide: the possibility of the formation of repeated shockproof layers, maintaining temperatures up to 400 degrees, increasing the density when added to plastic.

Every day more and more engine manufacturers are warning about the ineffectiveness of most cases of adding molybdenum additives to oils, especially new engines. This must be done using additional funds regular cleaning. Only in this case, the addition of molybdenum will meet expectations and will not harm the engine even more.

Additive pros and cons

After getting acquainted with the principle of operation, it became clear that additives with molybdenum have both significant advantages and significant disadvantages. Let's now systematize them for clarity.

The pluses include:

• low cost of the product compared to analogues;
• significant increase in wear resistance;
• good protective performance with regular and proper use.

The cons include:

• the need to add ;
• fuel and oil costs are not reduced;
• regular use without cleaning can cause additional damage to parts.

Can molybdenum additives be used for restoration work? Yes, but subject to complete cleaning after use. If you ignore the oil change procedure, the engine will become dirty and coke much faster. Continuous use in oil is effective for those drivers who can take the time to properly carry out the addition and refining procedures. As a rule, this does not take much time, but regular conduct is noticeably annoying. It is worth remembering that molybdenum additives are not intended to save money. Their main function is to protect parts from the damaging effects of friction.

Assortment and technical description

In any auto shop there are several representatives of molybdenum additives. But the most proven and popular of them are Liqui Moly products. This is a German company that specializes in the production of molybdenum-based products. Their additives are distributed all over the world and are in great demand in many areas of activity.

We are also interested in the range of molybdenum additives in the Liquid Moli engine. Let's take a closer look at them:

These are the most common and frequently used Liquid Moli products. Timely and correct use additives will help improve engine performance.

Results

Summing up, we can say that the regular and proper use of molybdenum additives has a positive effect on engine performance. negative consequences can be avoided by following the instructions for use.