The car owner must know the device of his car, be able to track not only the consumption of gasoline and replenish it in time, but also other indicators that affect the operation of the car. Consider what determines the consumption of automotive oil, why the oil level may decrease, and show you how to choose the right engine oil.

Modern auto companies note that there are many reasons that lead to increased consumption, or to a decrease in the level. Only the car owner himself is able to assess what kind of lubricating oil consumption is present in his car and there is a special dipstick for this.

Using this dipstick, the driver must independently check the oil level in the engine and monitor its consumption.

One of the first reasons for the increase in consumption, according to experts, is the poor quality of the oil.

The ability of automobile oil to neutralize acidic elements that are formed during the combustion process determines the quality of engine oil.

More on the topic

Oil consumption

Part of the engine oil, while performing its functions, burns out. Thus, oil consumption is a completely natural process. Well-tuned engines use 0.2 liters of oil every 1000 km. Audi calls the maximum allowable consumption of 1.0 liters of lubricant for every 1000 km. How much oil your Audi A4 uses depends on the following:

• an excessive amount of oil leads to its greater consumption, because through the crankcase ventilation, excess oil is blown into the engine;
• thin oil burns faster than thick oil. Seasonal oil in a heated state becomes liquid like water, and its consumption increases accordingly. All-weather oil stays thick; this entails its lower consumption - this is especially noticeable on long trips;
• All-season oil left in the engine for too long thins slightly, losing its highest viscosity grade, and the need for its addition increases accordingly.
• a sharp driving style at high engine speeds, in addition to increasing fuel consumption, also increases oil consumption. This is especially evident when the new engine immediately starts to work with full load.
• during break-in, the engine needs a little more lubrication than usual.
• leakage. Check everything as described in chapter Engines.
• a defect in the engine itself; e.g. defective valve stem gaskets, too much clearance between the valve guide and valve stem, defective piston rings or incorrect assembly during repairs, damage to the cylinder wall due to wear or piston seizure.

Lack of oil consumption is suspicious

In winter, when driving short distances, it happens that the oil level from measurement to measurement does not decrease, but even rises. There is no reason to be happy here, since this means that the engine oil is diluted with fuel or water condensate. These “additives”, which significantly impair the lubricating qualities of the oil, must be “boiled out” by regular long driving in order for the condensate to evaporate. Then you need to immediately measure the oil level, because after evaporation of gasoline or water that got into the oil, its level will drop sharply! When driving exclusively in extreme urban driving without intermediate long-distance trips, it is recommended to change the oil more often than at the intervals indicated above, for example every 3000 km or every four months.

In winter, an oil consumption of 2-3% should be taken into account, while our injection engines contain less gasoline in the oil with a dosed enrichment of the working mixture during a cold engine start than in older carbureted engines.

Oil consumption

Part of the engine oil burns out during the lubricating action. So oil consumption is a completely natural process. Well-run engines consume 0.2 liters per 1000 km, Audi calls the maximum allowable consumption of 1.0 liters per 1000 km.

The oil consumption of your Audi 80 depends on the following circumstances:

• Overflowing oil results in high consumption because the crankcase ventilation blows out excess oil.
• Thin oil burns faster than thick oil. Seasonal oil becomes liquid like water when heated, and consumption increases accordingly. All-weather oil remains more viscous; first of all, those who drive long distances may notice a lower consumption of this oil.
• All-season oil that stays in the engine for too long becomes thinner, the higher viscosity grade is “lost”, and the need for topping up increases accordingly.
• A sharp driving style, in addition to increased gas mileage, also increases oil consumption. This is especially noticeable if the new engine is immediately subjected to heavy loads.
• During break-in, the engine needs more lubricant.
• Engine leakage. Check according to the scheme described in the chapter Engines.
• Defect in the engine; e.g. defective valve stem seal (valve stem seal), excessive clearance between valve guide and valve seal, defective piston rings or incorrectly installed piston rings

Zero oil consumption is suspect

During winter operation over short distances, it may also be that the oil level between measurements does not decrease at all or even increases. This is absolutely no reason to be happy, because it means that the engine oil is diluted with fuel or condensate. This changing oil must be "boiled" during regular long-distance driving to allow the condensation to evaporate. At the end of the trip, the oil level should be checked, because it will drop significantly due to the evaporation of parts of the gasoline and condensate! For extreme city driving without long distance trips in between, it's better if you change the oil earlier than usual; perhaps already after 3000 km or four months.

In winter, one should reckon with an admixture of gasoline in oil of about 2-3%, and due to the better dosed enrichment of the combustible mixture in our injection engines, when starting a cold engine, less gasoline enters the oil than in old carburetors.

Correct oil specification

Since relatively long oil change intervals of 15,000 km run the risk of deposits in the oil sump, Audi has issued strict oil regulations.

• Ordinary mineral oil must comply with Volkswagen Standard 50101 (VW-Norm 50101). In this case, it has sufficient cleaning properties to prevent the formation of sediment.
• Oils with good anti-friction properties reduce internal friction in the engine. They must comply with the 500 00 standard (VW-Norm 500 00).
• Only in the event that the oil listed above is not available, you can use all-weather or seasonal oil of the categories "API SF" and "API SG" for topping up.

Oil viscosity

The fluidity of the oil, that is, its viscosity, must meet the requirements for use in this engine. In doing so, two criteria should be kept in mind:

• The oil should not be too viscous, as the starter must be able to crank a cold engine, and the places where oil enters in the engine must be lubricated immediately after starting a cold engine.
• The oil should not be too thin, because at high temperatures and engine speeds, the lubricating film may break.

SAE classes

The American Society of Automotive Engineers has classified oils into classes according to their viscosity.

Seasonal oil

These classes start with motor oils from liquid winter (winter) oils SAE 5W, 10W, 15W through the intermediate stage SAE 20W / 20 to viscous summer oils SAE 30, 40 and 50.

The cheapest motor oil used to be seasonal oil. For perfect lubrication of the engine, it must be filled with viscous or liquid seasonal oil according to the season. Seasonal oil is almost impossible to find at gas stations or supermarkets today, but it is still often used in fleets. For use in the Audi 80, it is suitable (and this is the opinion of the manufacturer) only as a temporary solution in a hopeless situation.

All-weather oil

The production of multigrade oil used today is more complex and therefore multigrade oil is correspondingly more expensive than seasonal oil. As a viscosity index improver, it contains long chains of molecules that "swell" when heated and lose volume again when cooled. In this case, the oil can "elastically" adapt to temperatures and cover many viscosity classes. SAE 15W-50 oil corresponds to a viscosity class of 15W at -15°C and a viscosity class of 50 at 100°C.

Problematic with multigrade oils based on mineral oils is the fact that the chains of molecules that improve viscosity decompose over time and in this case the oil becomes not so resistant to temperature effects. For this reason, Audi does not permit the use of SAE 10W-30 and 10W-40 multigrade oils in its vehicles during the warm season.

The problem of engine oil consumption worries many motorists. As you know, lubricant consumption is one of the important indicators of the general condition of the engine. From some car owners you can hear that the engine does not take oil, that is, the level remains the same or remains within acceptable limits from replacement to replacement.

Others note increased or high oil consumption in the engine, which makes it necessary. We note right away that the manufacturers themselves separately indicate the norms for oil consumption in the engine. This means that the power unit can consume lubricant within certain limits, and such consumption is not a malfunction.

This phenomenon is commonly referred to as oil consumption for waste. However, exceeding the norm for adding oil to the engine may well indicate problems with the internal combustion engine, motor, etc.

In this article, we will consider what kind of "oil appetite" of various power units can be considered acceptable, as well as what factors and features affect the consumption of lubricant in an internal combustion engine.

So, let's start with the fact that all engines consume engine oil to a greater or lesser extent. This happens taking into account the design features of the internal combustion engine, namely because of the urgent need to lubricate components and parts. In other words, the main loss of lubricant occurs as a result of the need to supply lubricant to the cylinder walls.

This area in the engine is a heat-loaded area. For this reason, partial evaporation and combustion of the lubricant occurs. Also, part of the oil is not removed from the cylinder walls, as a result of which the remaining lubricant burns along with the fuel in the combustion chamber.

As a rule, in modern engines, the declared oil consumption is, on average, from 0.1 to 0.3% of the total fuel consumption that was spent to overcome any segment of the path. It turns out that if the car has traveled 100 km, and the consumption is 10 liters of fuel, then the consumption of an average of 20 grams of oil will also be the norm.

It turns out that the lubricant consumption can be considered acceptable if it does not exceed the mark of about 3 liters. per 10 thousand kilometers traveled. It is also important to understand that the consumption rate will greatly depend on the type of engine, its degree, etc.

For example, for many gasoline ICEs, the norm is about 0.1%. On gasoline turbo engines, the consumption rate is noticeably higher. As for the declared lubricant consumption, the norm will be more than any gasoline analogue and averages from 0.8 to 3%. The indicated 3% are consumed by forced turbodiesels with two turbines, etc.

You can also separately mention rotary motors, which are particularly prone to lubricating fluid consumption. Such units (taking into account their fully operational condition) consume about 1-1.2 liters of oil per 1000 km. run. For reference, the manuals for different engines indicate that the rate of oil consumption for waste is 1 liter per 3 thousand kilometers traveled, that is, about 3 liters per 10 thousand km.

At the same time, manufacturers also note that the consumption directly depends both on the technical condition of the internal combustion engine and on the characteristics of the operation of a particular vehicle (load on the unit, speed, etc.)

What determines the oil consumption in the engine and how to reduce it

As mentioned above, oil is consumed in any engine, since the oil film on the parts to protect against dry friction burns in the chamber along with the fuel charge. If we add to this the natural wear of the internal combustion engine during operation, then the consumption of lubricant increases further.

However, it becomes quite obvious that 3 liters of oil per 10 thousand km. for a small car with an in-line aspirated engine, it can be considered a large expense, while for a powerful unit with a large displacement, this is a completely acceptable indicator. Practice shows that even if the engine began to “eat” oil above the norm, it is more economically profitable to simply add lubricant than to immediately overhaul the engine only because of increased consumption.

The fact is that at many service stations, masters prefer not to diagnose a separate cause of increased oil consumption, but immediately offer the owner to make a major overhaul. It is important to bear in mind that such expensive repairs are not always necessary.

• First of all, lubricant consumption can be increased due to the fact that oil flows out of the motor. In this case, it is enough to replace the gaskets and seals. As a rule, you need to pay attention to, camshaft oil seals, etc.

In various situations, grease can flow on the outer surface (leak out) and also penetrate into other systems. For example, if the crankshaft oil seal is to blame, and a puddle may form under the car.

• If the oil is actively consumed in the engine for waste,. In this case, especially compared to a leak, it is much more difficult to establish the cause without disassembling the engine.

However, even in such a situation, you can try to fight the waste before agreeing to a repair. First of all, the lubricant consumption depends on the mode of operation of the motor. In other words, driving at high speeds leads to an increase in temperature and loads, the oil liquefies, it is worse for rings to be removed from the cylinder walls, it burns out, etc.

• It is also important to understand that the lubricant may not be suitable for the engine in certain parameters. This means that you need to know which oil to choose for the engine and what features to consider.

If the motor is worn out, then in parallel it is necessary to take into account the features of the selection of oil for engines with high mileage. In a nutshell, the reduced viscosity material forms a thin film that the oil rings cannot remove from the walls. If the lubricant is thick, then the film is very thick, while the rings cannot remove such a layer in full.

With this in mind, it becomes clear that you need to use the most suitable oil both in terms of tolerances and in terms of high temperature viscosity index. For example, from the list of recommended lubricants in the manual, you need to select a product with a higher viscosity compared to what is currently filled.

Each of the solutions has both its pros and cons, however, for a worn engine, in many cases it is possible to reduce lubricant consumption and.

• Increasing the pressure in the crankcase also causes excessive consumption of lubricant. In simple words, high pressure crankcase gases causes oil to end up where it should not be.

As a result, the lubricant enters the cylinders through the intake, after which it burns out in the engine along with the fuel. In such a situation, it is necessary to diagnose and clean the crankcase ventilation system.

• Problems with also lead to lubrication leaks in the supercharger area, oil also enters the cylinders through the intake, etc.
  The solution requires diagnostics and repair of the turbine. In extreme cases, you can replace the turbocharger, while the lubricant consumption will also decrease.

What is the result

In view of the foregoing, we can conclude that the main reason for an engine overhaul is the presence of significant defects and damage, as well as high wear of parts and wear on the cylinder walls (seizures, changes in geometry, etc.).

In this case, eliminating the “zhor” of the oil only by decoking, replacing rings, valve stem seals, or switching to a more viscous lubricant will no longer work. Typically, engines with such damage have low compression, start poorly both cold and hot, and lose power significantly.

During operation of the unit, knocks and extraneous noises may be present. As a rule, after disassembly and troubleshooting, the block must be bored/sleeved, the crankshaft must be ground, etc. In other words, a major overhaul is needed.

If the engine is worn out, but it works normally, while the oil consumption is above the norm, then you should not expect an instant increase in lubricant consumption. Lubricant will be consumed more and more, but this problem will progress slowly.

It turns out by adding several liters of lubricant for every 10 thousand km. will allow such a motor to be operated for more than one tens of thousands of kilometers without major repairs (if no other breakdowns occur). At the same time, it is more profitable to top up the lubricant than to repair the motor.

Additionally, the use of a more viscous oil, replacement of valve seals and cleaning of the crankcase ventilation system will help reduce overall lubricant consumption and the cost of maintaining and servicing the internal combustion engine.

Read also

How to choose the right engine oil for an old internal combustion engine or engine with a mileage of more than 150-200 thousand km. What you need to pay attention to, useful tips.

Use of anti-wear, anti-smoke and other additives to reduce oil consumption. Pros and cons after applying the additive to the engine.

Oil is leaking

When oil leaks, it is necessary to change gaskets, seals, etc.

Engine oil is leaking in the following places:

1. Valve cover gasket. This gasket is located on top of the engine; if the seal is not tight enough, oil leakage is clearly visible on the outer side walls of the engine. A lot of oil cannot flow through this gasket. The tightness of the system must always be restored.
2. Cylinder head gasket (cylinder head). It, like the valve cover gasket, is located on top of the engine under the cylinder head. In V-shaped motors, there are two of them, like the cylinder head. Oil from it can leak out, as a result of gasket damage (reasons are identical with the valve cover gasket). Oil can leak into the cooling system if the gasket between the holes in the cooling system and the working cylinders is broken. The engine will be dry on the outside, and the coolant (coolant) will be cloudy and change color, the oil will foam (foam can be observed on the inner surface of the filler cap). This problem requires urgent intervention, because. it is not safe for the engine.
3. Crankshaft and camshaft seals. This problem is visible by the presence of oil stains on the inner surface of the crankcase, and by a smudge from the bottom of the engine.
4. Oil pan gasket. This leak is visible only on the lift or when the protection is removed.
5. Rear crankshaft oil seal (at the gearbox inlet). This leak can only be observed if the stuffing box is replaced with the box removed. The consequences are visible on the smudges in the lower part of the engine.
6. Oil filter gasket. The solution to the problem is the quality of the filter and its replacement.

Engine oil waste.

The presence of engine oil burnout is easy to detect. Oil burning in the engine produces blue smoke in the exhaust, which cannot happen when gasoline is burned. If an oily black rim forms around the edges of the exhaust pipe, the oil burns unnecessarily.

The reason for the increased oil consumption in the engine can be seen by opening it. There are simple and inexpensive ways to deal with fumes, performed before opening the engine.

The oil is not able to burn out completely in the engine, because. it forms an oil film on the inner sides of the working cylinders, where the fuel ignites.

There is a direct relationship between the burnt oil and the operating mode of the engine. The more revolutions the motor makes, the more oil in the engine will burn, and this does not depend on the motor. The laws of physics apply - the more revolutions - the more temperature engine and engine oil, less often oil and, accordingly, more of it remains in the working cylinders.

Before announcing the verdict on your own engine, it is necessary to take into account the mode of operation of the motor and its design features. Regarding some features, it is necessary to refer to official representative car brands or find the necessary information on the net.

Let's move on to the main causes of increased oil consumption in the engine

• The engine contains oil that is not suitable for the parameters. If the oil stays in the cylinder and burns out, then it was low viscosity, and if the oil forms a thick film on the inner walls, the oil is too high viscosity. The oil will burn anyway. The solution to the problem is simple - choose the right oil. Therefore, from all alternatives, it is necessary to choose an oil that will be higher in viscosity than the oil that was in the engine. One solution to oil consumption is to switch from synthetic oil to a semi-synthetic product. Semi-synthetic oils with these parameters, which meet the recommendations of car manufacturers, do not cause any harm to your engine.
• The valve seals are worn out. These seals are not expensive to replace, without touching the cylinder head (cylinder head). Oil consumption will be less. The reason for the wear of the valve seals is the temperature difference, the wrong oil, which is incompatible with rubber.
• Wear of piston (oil scraper) rings. Replacement leads to a major overhaul of the motor. You can carry out the "decoking" of the rings. Its essence is the exit to the highway and the passage of a couple of tens of kilometers at high speed. There is also a special chemistry that is added to the spark plug holes, although the safety of the engine is questionable.
• Violation or wear of the “insides” of the cylinders and all engine parts. This can be detected by extraneous sounds in a running engine. The use of foreign additives, low-quality oil, oil and filters not changed on time, dust and dirt getting into the engine, etc. - the cause of the problem. With a high mileage or age of the engine, it is impossible to increase oil consumption, it is consumed gradually and slowly.
• It is necessary to change to a more viscous oil when replacing valve seals, observe the change in oil consumption. If the changes amount to several liters between changes, then it will be more beneficial for you to simply add oil. Overhaul is not the best optimal solution, because it may not be successful.