Oil consumption: frying pan in a cylinder. Engine oil leaks: reasons, tips for fixing the problem

Where does the oil go?

In many ways, the problem with high oil consumption is associated with the design of modern engines, which have a high compression ratio, which makes it easier for gases to escape through the piston rings.
In addition, most modern engines are turbocharged, and some oil inevitably gets into the supercharger. Therefore, one of the most common reasons for a decrease in engine oil volume is its waste. The lubricant simply burns along with the fuel, depositing black soot on the walls of the pistons and cylinders.

Oil consumption for diesel engine waste: calculation

Diesel engines, unlike gasoline engines, have been more voracious in terms of oil consumption throughout all periods of the automotive industry. The point is in the specifics of the work: the compression ratio and, in general, the voltage on the crankshaft parts of diesel engines is higher.

Often motorists do not know how to independently calculate the oil consumption of the engine due to waste. To date, several methods are known.

The first and simplest is the topping method. Initially, during the next maintenance, you need to fill the oil strictly according to the upper mark on the dipstick. After 1000 km, gradually add oil from a liter container until the same level is reached. Based on the residue in the canister, you can understand how much oil the car consumed due to waste. Control measurements should be made under the same conditions as at the time of maintenance. For example, if the oil level was checked on a hot engine, then after topping up this should be done under the same conditions. Otherwise, the result obtained may differ significantly from the actual oil consumption of the engine.

The second method will give a more accurate result. Completely drain the oil from the crankcase during maintenance. Fill it fresh to the top mark on the dipstick and check how much is left in the canister. For example, we pour the remainder into a measuring container for a more accurate result, but you can also use the measuring scale on the canister as a guide. We subtract the remainder from the nominal volume of the canister - we get the amount of oil poured into the engine. While driving, over 15 thousand km (or other mileage regulated by the car manufacturer), add oil to the mark and count it. It’s most convenient to simply top up with liter jars. Typically the difference between the marks on the dipstick is about a liter. After the next maintenance, drain the oil from the crankcase and measure its quantity. We subtract the amount of drained waste from the initially filled volume of oil. To the resulting value we add the entire volume of lubricant that was filled in over 15 thousand kilometers. We divide the resulting value by 15. This will be the volume of oil that burns out per 1000 km of run in your car. The advantage of this method is a large sample, which eliminates operational errors that are typical for measurements at short mileage.

It will be useful: Brake fluid for Renault Logan: selection, replacement

Then we simply compare the obtained value with the passport data. If the waste consumption is within the norm, we drive on and don’t worry. If it exceeds the passport values, it is advisable to carry out diagnostics and find out the reasons for the increased oil consumption.

Is it normal to eat oil?

It turns out that modern car owners have no choice but to come to terms with the need to regularly check the oil level in the engine and add it as necessary. However, the car’s oil appetite can be somewhat moderated by doing more frequent maintenance and adhering to a calm driving style.

Normal oil consumption is considered to be approximately 0.5 percent of gasoline consumption. In other words, if during a service interval of 15 thousand kilometers your car has consumed 1200 liters of fuel, then normal oil consumption will be 400 grams of oil per 1 thousand kilometers.

Natural waste

In principle, any engine consumes engine oil “waste”. It inevitably remains on the cylinder wall after each downward stroke of the piston, and immediately burns out during the working cycle. The amount of oil not removed from the wall by the oil scraper ring depends on its properties, on the design of the engine and on the degree of wear of its cylinder-piston group and valve mechanism.

Many modern engines are structurally predisposed to “eating” oil (for example, some units of the VW Group, Subaru, etc.); often the operating manuals allow figures for its consumption of about 1.0 liters per 1000 km.

In fact, such an “oil appetite” on an unworn engine is not very common, although a warranty engineer at a dealer service station is always ready to show you exactly this figure. And yet, if on a new or almost new car you notice that the oil level in the engine has dropped sharply, immediately contact a service station - perhaps there is some emergency reason for this. By the way, a new engine with a mileage of up to 2000 - 3000 km almost always consumes more oil than a run-in unit.

Unnatural frenzy

The abnormal oil appetite of an engine with noticeable mileage is caused by wear of the cylinders, pistons and their rings, and valve seals. And if valve seals (oil seals) are, in principle, easy to replace, then replacing worn parts of the cylinder-piston group requires complete disassembly of the power unit - and this is serious work that requires qualifications from craftsmen and money from the owner.

Another option, even if the engine is not too worn out, is the so-called stuck rings. This means that due to carbon-clogged grooves in the piston, the rings lose mobility and do not fully perform their function, which is why a large amount of oil remains on the cylinder walls and burns. This problem can sometimes be solved by using flushing additives.

Oil consumption rate for waste

The oil consumption rate for waste is determined by the car manufacturer and is almost always indicated in the car's operating instructions. The figure that the manufacturer talks about usually indicates the maximum permissible oil consumption by the engine. After exceeding the threshold specified by the car manufacturer, the engine should at least be diagnosed, since with a high degree of probability the rings and valve stem seals have worn out and require replacement.

For some engines, the oil consumption rate for waste, so to speak, is somewhat indecent. For example, on M54 engines of BMW cars, consumption of up to 700 ml per 1000 km is considered the norm. That is, at the maximum permissible lubricant consumption, you will have to add approximately the same amount of oil between changes as is in the engine.

Why may the volume of oil poured into the engine decrease?

There are several reasons for engine oil consumption. Firstly, it can evaporate from the surface of cylinders that are operated at very high temperatures.

Secondly, a small amount of oil can enter (due to the lack of absolute tightness of the system) into the combustion chamber, where it ignites along with the incoming fuel mixture.

Important! New engines usually consume virtually no oil. Natural consumption appears as the internal combustion engine wears out.

On average, after traveling 1 thousand km, 100 to 300 ml of liquid can be lost. If the car is operated under load, a consumption of up to 400 ml/1000 km is acceptable. A fairly worn engine, whose mileage exceeds 150,000 km, may lose 500 ml during operation.

Natural consumption rates vary significantly depending on the type of power unit.

What is the oil consumption in a naturally aspirated engine?

Cars with naturally aspirated engines running on gasoline are the most common among all operating vehicles with internal combustion engines. For relatively new power units, the standard lubricant consumption rate is 5...30 ml per 1 thousand kilometers traveled.

Sufficiently worn engines can burn about 100 ml of oil. When operating a car in difficult conditions, you should be prepared to increase the flow rate to 500...600 ml.

Consumption rate for turbocharged engines

More and more cars are appearing on the market equipped with engines that can have from one to three turbines installed. They are characterized by both their gluttony for fuel and their high consumption of lubricating fluids (the more turbines, the higher the losses).

Even new equipment can consume about 80 ml of oil when burning every 100 liters of fuel mixture.

Oil consumption standards for diesel internal combustion engines

If during operation of a diesel engine there is a loss of up to 500 ml of lubricant for every 100 liters of fuel burned, there is no reason to worry. However, if you start spending more, there is a reason to bring the car in for diagnostics.

Extreme vehicle operating conditions also affect oil consumption. High speeds of the power unit, at which an increase in temperature is observed, lead to increased losses. Aggressive driving style or driving in mountainous areas causes more frequent addition of lubricant.

In the winter season, more oil is also consumed than in the warm season. A thick, more viscous lubricant is not able to quickly create the film required for engine operation. Therefore, it is recommended to warm up the engine for several minutes to minimize wear on the rings and cylinder block walls.

Experts advise changing the oil before the onset of cold weather. A new lubricant that has not lost its properties will help the engine operate normally in difficult conditions.

As you can see, engine oil can drain naturally. An increase in its consumption is due to a number of reasons.

How is engine oil consumption calculated?

To determine the norm, it is not the mileage value that is taken into account, but the fuel consumption. This indicator is more accurate than the distance traveled, because when you are stuck in traffic jams, the oil is depleted even more, and the odometer does not change its value.

Engine oil consumption is usually calculated based on the volume spent on burning 100 liters of fuel.

To find out the oil consumption rate in your car's engine, you need to use a calculation formula and a calculator, or use this online form. It involves calculating the permissible amount of oil for waste according to the type of engine, the volume of operating oil and the amount of fuel consumed, taking into account the condition of the piston group.

Calculation formulas for oil consumption

The total actual oil consumption for waste during its operating cycle (from replacement to replacement) can be calculated using the formula:

Where ∑q is the oil added during the cycle (between maintenance); Qз - filled during refueling; Qsl – drained during replacement.

But the consumption of poured oil in liters per 100 liters of fuel is determined as follows:

Where V is the capacity of the engine lubrication system; P – consumed fuel k – coefficient taking into account wear of the piston group (k – for a diesel car 1.25; petrol 1.15; turbo 1.3).

Regular passport expense

Oil leaves the engine for various reasons. All of them can be divided into 2 groups. The reasons for the decrease in lubrication in power units may be:

standard and certified, focused on permissible oil consumption standards;
abnormal, caused by breakdowns of individual components.

Modern engines are characterized by established standards regarding lubricant consumption. Indicators that are within 0.1–0.3% of total fuel consumption are considered normal. For large diesel engines, the standard consumption is 0.8–3.0%. Car manufacturers try to indicate the rated lubricant consumption caused by natural waste. It is necessary to focus on these indicators so as not to sound the alarm ahead of time.

Burnout in the cylinder-piston group

For successful and durable operation of the power apparatus, lubricant invariably enters the working area of the cylinder-piston group. With intense mechanical friction and increased temperature conditions, the lubricant heats up, evaporates and burns out. This results in wasteful oil consumption. The tolerances for such natural losses are based on the type of engine and its condition.

For ease of calculation, oil consumption indicators depending on the amount of fuel are converted into a ratio with mileage. New gasoline engines consume 5–25 g of lubricant per 1000 km. Worn-out motors consume up to 100 g. 400–600 g may indicate the approaching condition of repair. The 800 g mark is considered critical.

Turbocharged gasoline engines have increased oil consumption. New engines can consume 80 g per 1000 km. Worn power units of this type absorb up to 2 liters. If the turbine is faulty, the consumption increases. Lubricant consumption in excess of 2 liters is considered critical.

The natural waste of diesel engine oil approaches the performance of a turbocharged power unit. The norm is 300–500 g per 10,000 km. The threshold of 2 liters is also considered dangerous for engine operation.

Flow due to crankcase ventilation system and turbocharger

Increased crankcase gas pressure is observed in worn-out engines. Then oil is carried to the inlet of the power unit, the loss of which is almost inevitable. During intensive use, a worn-out motor often operates at its limit. The crankcase gas velocities increase and the pressure increases. The oil has nowhere to go; it is pushed into the cylinders through fuel injection.

A similar mechanism is triggered when the turbine (turbocharger) has deteriorated. In addition, oil is also used to lubricate the turbocharger itself. This increases the standard lubricant consumption.

Abnormal lubricant consumption is often a harbinger of upcoming problems. Therefore, it is very important to pay attention in time to increased oil consumption in the engine or external leaks. A car enthusiast cannot remain indifferent when he notices oil spots under the engine. Then it is necessary to investigate in what ways the lubricant manages to escape from the engine.

How to use the calculator

One of the main roles in this calculation is played by the volume of fuel burned and the volume of operating oil, as well as the type of engine. It is in relation to this volume and specifics of work that the specific oil consumption is calculated.

To calculate specific engine oil consumption, the following data is required:

In the “fuel” field, enter the average fuel consumption in liters per 1`000 km. mileage (by default and based on calculation formulas this is 100 liters);
In the “oil” field - the volume of oil that is regulated by the manufacturer as necessary when filling;
Select the engine type and check if the machine has been in use for more than 5 years
Click "calculate".

Such a calculation calculator can be an indispensable assistant for calculating the consumption rate of lubricants intended for operational accounting of the specific consumption of motor oil when justifying the need for them. After all, if not all, then many car enthusiasts have a rather wary attitude towards engine oil consumption. This service will show whether you are within the nominal values. If not, then you will have an objective reason to look for reasons and possible problems.

What's the outcome

That is, if the engine is in order, then it takes practically no oil, and you will not need to top it up until the next change. Its level will be within acceptable limits on the dipstick (within the min./max. marks). But there are cases when the manufacturer indicates consumption rates for a specific power unit (some engines eat oil), then topping it up is considered natural and is not a malfunction, but on average it does not exceed 1-2 glasses from replacement to replacement.

It is important to understand that the harder the engine runs, the more oil it burns. For example, the higher the number of revolutions, the more oil will remain in the cylinders of the car engine. Although we should not forget not only about the operating mode of the engine, but also its design. You should also not neglect the tolerances of motor oils and fill in fuels and lubricants of dubious quality.

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Even more useful tips in a convenient format

What is high oil consumption?

I found some information on the net from the officials

The oil consumption rate for waste for all types of Mitsubishi engines is no more than 1 liter per 3000 km (or 3 l/10,000 km or 5 l/15,000 km).

Official response from the MMC representative office

During normal operation for Mitsubishi cars, the Manufacturer considers acceptable engine oil consumption not exceeding 1 l/3000 km. Please note that oil consumption depends not only on the technical condition of the engine, but also on the operating characteristics of the vehicle, such as road conditions, speed, vehicle load, etc. The specified standard is provided for all Mitsubishi car models, regardless of type, engine size and configuration.

Where does the engine oil go if the car doesn't smoke?

To answer this question, you need to study in detail all the places in the engine through which oil can leak. For this, a white sheet of paper is best suited, which should be left under the engine overnight. The next morning, by the location of the spots on the surface of the paper, you can determine the place where the leak is coming from.

It should be remembered that you need to focus on the yellow spots. After all, if the oil spots are red, then this is most likely a lubricant leak from the automatic transmission or power steering.

If no stains are found on the sheet, you need to look for leaks in the most likely areas:

You need to carefully inspect the gasket under the valve cover. If there are clear oil streaks on the outer surface of the engine, then we can assume that the problem has been found. To solve the problem, you need to replace the gaskets under the valve covers or apply sealant.

Inspection of the pan gasket. This gasket may be worn. The solution to the problem is to replace the gasket. In this case, it is important to purchase a gasket that, according to the catalog, fully matches a specific car. It is not recommended to install gaskets from another car, especially one with signs of wear. Otherwise, the oil leak story may soon repeat itself.

Penetration of the pallet body when hitting a solid obstacle. In such a situation, you either need to replace the entire pan or, if the hole is not very large, you can try to weld it. You cannot use various cold welds to eliminate the leak. Indeed, under the influence of oil pressure, such temporary sealants do not provide a long-term effect and lead to repeated failure, during which a significant amount of oil is lost.

Oil seal failure. You need to immediately pay attention to the condition of the front oil seal mounted on the crankshaft. The seals located on the camshaft can also leak. It is very difficult to visually verify that the seal is leaking. It must be remembered that the main sign of oil leakage through the oil seal may be their strong fogging and excessive oiling of the place where they are attached. If the cause of the leak is in the oil seal, it needs to be changed as quickly as possible, since engine oil can get through worn oil seals onto other engine parts.

Lubricant may be leaking from the oil pressure sensor. In this case, you need to carefully tighten the sensor using a wrench. Perhaps the sensor is not screwed in correctly at all and has a technical defect. As for sensors, to avoid a similar situation, you need to purchase only original sensors and under no circumstances run for a low price. Otherwise, you can buy a Chinese fake of low quality and a bunch of future problems.

Oil may be leaking through an oil filter that has a defective housing or is simply not tightened tightly enough. In many cars, the oil filter is installed at the bottom of the pan and can be damaged if it hits a hard object. Sometimes, the thread in the filter may simply be torn off, which prevents it from being tightened tightly enough.

The camshaft plug also deserves close attention, especially for engines with two camshafts and no distributor. Here, oil may leak out through the O-ring. In such a situation, you need to replace the plug itself. It can be made of plastic and rubber. Both options are quite acceptable, but the rubber plug will last longer. Although in practice, replacing the plastic plug is faster and easier.

Lubricant can leak through a damaged distributor o-ring. To eliminate the leak, you need to replace the O-ring and re-adjust the OZ.

It is much more difficult to eliminate a leak if oil gets into the distributor itself. The main sign of the presence of oil in the distributor is a specific crackling sound similar to the crackling sound of a bearing. To correct this situation, it is necessary to disassemble the distributor itself, clean it and replace the bearing with the seal.

Important to know: Engine oil consumption per 10 thousand mileage?

When checking the oil level, a natural question that most motorists have is where does it disappear and is everything okay with the “heart” of our car - the engine. Most car enthusiasts consider it normal if you don’t have to add oil from replacement to replacement ( between the marks on the dipstick min and max is usually 1 liter

). For example: you have decided to change the oil every ten thousand kilometers; your car, or rather the engine, will take no more than 100 grams per 1000 km.

It's no secret that when an engine operates, no matter how ideal it is, a certain amount of oil burns. In any engine, there will still be oil losses, no matter what you do, our main task is to achieve minimal, optimal losses for our engine - if we top up, then minimal.

That is, it will approach the ideal operating mode of the engine, in which losses occur only from the combustion of residues on the cylinder walls. But you can’t do anything about such losses, alas, this is the purpose of our oil - to cover all the internal surfaces of the engine with a film and prevent dry friction. The oil film burns in the cylinder along with the fuel mixture.

Thus, oil consumption is a completely natural process. In the era of turbo engines, this issue has become relevant for engines with low mileage.

Manufacturers honestly indicate oil consumption when the engine is running, but at the same time they are a little disingenuous, indicating the maximum possible. For example, the Audi company in the operating instructions for one popular model indicated oil consumption of 1 liter per 1000 km. How do you like it?! What will happen to our wallet in this case? From life - During normal operation, most engines consume (consume) 100-200 grams of oil for every 1000 km.

Reasons for engine oil consumption in an internal combustion engine:

exceeding the maximum oil level (high oil level in the engine) leads to greater oil consumption due to the release of excess oil through the crankcase ventilation; the volume of oil in the engine can be clarified in the section of our catalogue;
mismatch of engine oil, thin oil burns much faster than thick oil. So, for example, seasonal oil when heated becomes liquid like water, which leads to an increase in its consumption. All-season oil remains thick, oil consumption decreases - this is especially noticeable on long trips;
multi-grade oil that remains in the engine for too long dilutes slightly, loses viscosity, and accordingly the need for topping up increases;
your driving style. At high engine speeds, oil consumption increases. This is especially noticeable when operating a new car with an engine under full load. So, during break-in, the engine requires a little more lubrication than after, during normal operation.
possible leakage (leakage), check for oil traces on the engine;
engine defect. Defective valve stem seals, too large a gap between the valve guide and the valve stem, defects in the piston rings (wear), damage to the cylinder wall (wear-out) due to natural wear or scuffing of the piston.

Exceeding the maximum oil level

The engine oil level in the engine is higher than normal (the normal level is between the min and max marks on the dipstick) - an increase in volume, oil pressure in the engine - release of excess engine oil through the crankcase ventilation.

All this leads to an increase in consumption - loss of engine oil, formation of carbon deposits on the bottom of the pistons, the inner surface of the combustion chamber, premature failure of the exhaust system, exhaust gases become more toxic - CO...

It is not in vain that the manufacturer, when designing, testing and bringing the motor to optimal parameters (characteristics, service life), determines the minimum and maximum volume of lubricant. Well, a purely practical question - why buy more engine oil than is required for replacement?!

Possible leakage (oil leakage)

The simplest thing at first glance, easily identified - the reason for engine oil consumption is a leak. In principle, everything is clear - if there is oil on the engine, you need to change the gaskets, seals and off you go. Here are examples of the most common causes of engine oil leaking from the engine:

Motor oil
is a base oil and a set of additives that impart the required properties to the base oil. In the world of manufacturing bases there are tens of times fewer lubricant manufacturers.

Sami: Changing the engine oil

Causes of oil combustion: the oil used is not suitable for the parameters of this engine; wear of oil seals; wear of piston (oil scraper) rings; cylinder production; high pressure of crankcase gases.

Valve cover gasket

The valve cover is located at the top of the engine. A leak through the valve cover gasket is the most harmless, that is, the amount of engine oil leaking is minimal. The cause of the leak is natural aging of the gasket or poor-quality repair of the engine in which the gasket was damaged. Definition: drips on the outer side walls of the engine. If the gasket is not damaged, it is enough to tighten the fastening bolts (nuts).

Cylinder head gasket

A leaking head gasket is one of the most dangerous engine oil leaks. In most cases, there is a hidden leak, the gasket is damaged between the cylinder block and the cooling system. In this case, part of the engine oil will gradually displace the coolant, and part of the coolant will penetrate into the engine, which significantly reduces the service life. Definition: cloudiness of the coolant, foaming of the engine oil.

Camshaft and crankshaft oil seals

“Leaking like a bucket” in our case is the only way to characterize this type of leak - the maximum possible oil consumption for all possible damage. Definition: traces of oil, grease on the inner surface of the crankcase protection or lower part of the engine.

Rear crankshaft oil seal

It is found in most cases on cars with exorbitant mileage. In most cases, due to difficulties with elimination and minor oil losses (minimal), most car enthusiasts continue to operate the car until the gearbox (gearbox) comes out of service. To replace the oil seal in the vast majority of cars, disassembling the gearbox is necessary. Definition: leaks on the gearbox side.

Gasket under the oil filter

Yes, we were not mistaken; engine oil leaks from under the oil filter gasket are very common. It doesn't seem to be a tricky thing, but it's always worth checking. One good thing is that to eliminate it you only need your hands and a couple of minutes of free time, you just need to tighten it up. As we wrote earlier, any driver’s practice should include inspecting a car before a trip.

Category: Motor oils | Posted by: autocar | Naletsky Sergey Nikolaevich | | engine oil, oils, oil consumption

Worn or deformed crankshaft oil seals

The release of engine oil to the outside is often associated with wear or deformation of the sealing edges of the crankshaft oil seals. The processes of rubber aging and loss of elasticity are inevitable. However, oil seals can fail much earlier than expected. The causes of premature wear are:

use of a lubricant not provided by the engine manufacturer;
adding untested or low-quality additives;
a defect in the production of the oil seals themselves or the engine components.

Cases falling under these reasons will require replacement of the seals. It is important to select parts from good technical rubber that is compatible with various types of modern oils.

Where does the engine oil go: hidden reasons

Let's start with the fact that in addition to the obvious reasons for increased lubricant consumption (oil leakage), there are also indirect ones. For example, an internal combustion engine cooling system.

In simple words, a number of malfunctions in the engine cooling system, insufficiently efficient operation of this system can also lead to the so-called “oil burn”.

The reason is that insufficient heat is removed from the engine, the engine in turn becomes “hotter”, i.e. its operating temperature is forcibly increased by several degrees and the internal combustion engine operates at the upper temperature limit.

The oil recommended for use in various engines, according to its technical characteristics and tolerances, is designed to operate at lower temperatures, namely at the nominal temperature conditions of the internal combustion engine.

Accordingly, being constantly exposed to extreme temperatures, the oil intensively “burns”, and the waste products clog the oil channels, reducing the efficiency of the entire engine lubrication system.

Oddly enough, problems in the power system can also indirectly provoke increased engine oil consumption. The problem lies in the fuel injectors, which, without proper maintenance, over time begin not to spray the fuel mixture, ensuring uniform ignition in the cylinder, but pour fuel in a stream.

As a result, uneven combustion of fuel begins and increased detonation. In turn, increased detonation leads to the appearance of microcracks in the pistons and piston rings, as well as cylinders (liners). Due to these defects, oil scraper rings do not effectively remove the oil film from the working walls of the cylinders. It turns out that oil breaks into the combustion chamber with all the ensuing consequences.

Easy to fix troubles

The carelessness of the car owner often leads to problems with engine lubrication.

Problems requiring specialist intervention

High oil consumption can also be caused by more serious reasons. To fix the problem, it is often necessary to disassemble the engine.

Worn walls of the BC

The condition of the cylinder block walls may deteriorate over time due to natural aging or the appearance of defects (such as scratches). The cylinder can also change its shape (the cross-section becomes oval).

As a result, the O-rings do not provide the necessary tightness, which leads to oil leakage. The way out of the situation is:

or cylinder boring,
or using less rigid rings (this is not recommended),
or installing rings with a different geometry that compensates for the change in cylinder shape,
or replacing the entire unit.

In any case, in this case it is impossible to do without significant financial costs.

Deformation of cylinder block gaskets or oil filter

This is almost an emergency situation. It occurs as a result of improper tightening of power bolts or unacceptable overheating of the engine. Due to the deformation of the gasket, the quality fit of the power unit parts is disrupted. This defect is detected due to traces of oil on the surface of the engine block.

Sometimes the cause is eliminated by tightening the power bolts. But more often you have to change the gasket with a complete replacement of the lubricant. Indeed, with such a malfunction, antifreeze gets the opportunity to penetrate into the cylinder area. In order not to lose the engine, you need to react quickly.

Oil leakage occurs due to unprofessional replacement of the oil filter. It may be under-screwed or over-tightened. In any of these cases, the gasket is deformed and the tightness of its fit to the engine body is disrupted. There are mechanical defects in the filter itself. Then it's better to change it.

Wear of turbine seals and bearings

When there is play in the bearings and wear of the seals, the engine oil, which is supplied under pressure to the turbines, immediately enters the combustion chamber. And if the passage of the turbine is clogged with carbon deposits, then the oil, after being sucked into the combustion chamber, ends up in the exhaust pipe. To solve the problem, you will have to repair the turbocharger.

Worn high pressure fuel pump

In some cars, fuel injection pump parts are lubricated with oil rather than diesel fuel. When fuel pump parts wear out, oil consumption increases.

Fuel system malfunctions

Without regular maintenance, the fuel injectors of a diesel internal combustion engine begin to pour fuel in a stream instead of a soft spray, which causes uneven combustion of fuel in the cylinders and detonation.

Increased detonation leads to microcracks in the pistons and piston rings and cylinders. Such defects prevent the oil scraper rings from removing the oil film from the cylinder walls evenly and completely; the remaining oil burns out in the combustion chamber.

Cylinder head gasket failure

As a result of improper engine assembly, the head is pressed unevenly against the cylinder block, causing gasket breakdown. The malfunction can be determined visually: oil streaks will be visible from under the cylinder head.

Also, if the cylinder head gasket breaks, antifreeze can enter the engine crankcase and mix with the oil. In this case, there will be an increased oil level on the dipstick and an emulsion on the dipstick and plug.

You cannot start such a motor! It is better to deliver such a car by tow truck to the place of repair and replacement of the cylinder head gasket. Be sure to also change the oil and filter, and before that, flush the lubrication system.

"Hot" engine operating mode

When not enough heat is removed from the internal combustion engine, it has to operate at the upper temperature limit and the engine remains “hot”. Due to such a forced increase in temperature, the internal combustion engine operates at the maximum permissible temperature, the oil intensively “burns”, deposits of such carbon deposits clog the oil channels, interfering with the normal operation of the lubrication system.

This problem is especially typical for modern oil scraper turbodiesels.

Crankshaft oil seal wear

This problem is easy to identify: there will be an oil puddle under the car or the exhaust will take on a bluish tint. But sometimes, for an accurate diagnosis, you will need to carefully examine the underbody of the car.

Since rubber is used to make the crankshaft oil seal, which is subject to mechanical wear over time, the best solution is to simply replace the oil seal. And also for preventive purposes, after replacing the oil seal, it is recommended to fill in new engine oil and replace the filter.

Valve seals fail

Oil seals or oil seals are one of the rather vulnerable points in the engine design. These structural parts are located in the cylinder head. The operating temperature in the area where the caps are located is approaching critical. The rubber part of the seals loses elasticity and hardens. Sealing abilities are reduced. Oil breaks into the CPG and forms deposits on the surface of the valves. The coordinated work of many components is disrupted.

Wear, overheating, coking of piston rings

In the process of natural mechanical wear of rubbing parts, oil scraper rings “get tired” before others. They receive the smallest amount of lubricant because they protect oil leakage paths. Wear of oil scraper rings leads to increased oil losses.

The elasticity of the rings is lost due to severe overheating. After this, the engine’s oil appetite increases noticeably. Sometimes very sharply and rapidly.

For many reasons, rings can become stuck or coked. The use of oil with poor cleaning properties contributes to such breakdowns. Coked rings cannot maintain proper tightness in the cylinders, and the oil finds new leakage paths.

Warping, increased wear of cylinders and valve bridges

The process of intensive engine operation can lead to deformation of the cylinders. Such processes are very typical for air-cooled engines. Crescent-shaped gaps appear between the rubbing surfaces of the rings and cylinders. They indicate to the oil where it can slip out.

Cylinder wear manifests itself in an increase in their diameter. Chips, scuffs, and scratches may also appear. Such damage creates peculiar oil pockets. The rings cannot tightly block the path of the lubricant, the amount of which in the engine invariably decreases.

A common cause is the destruction of piston inter-valve bridges. Failure occurs as a result of thermal fatigue of the rubbing elements. In this case, losses in the combustion chamber seals and wear of the piston group are observed.

Problematic oils

A high degree of viscosity of the lubricant can cause increased waste. This situation becomes especially relevant for worn-out engines.

Oil leakage is caused by its quality characteristics. The entry of counterfeit or low-quality lubricant into the motor leads to increased waste and deformation of the sealing parts. Bad oil makes its own way out of the engine.

Here are the main reasons for increased oil consumption. A caring car enthusiast will be attentive to their manifestations. Then larger problems can be avoided.

Shizgar › Blog › Oil consumption, oil waste or everything about motor oil!

What is high oil consumption?

I found some information on the net from the officials

The oil consumption rate for waste for all types of Mitsubishi engines is no more than 1 liter per 3000 km (or 3 l/10,000 km or 5 l/15,000 km).

Official response from the MMC representative office

The guy talks about the theory of internal combustion engines and talks a lot but to the point:

To begin with, a rhetorical question: is a liter of oil per 5000 km a lot or a little? Everything is individual, for V6 or V8 engines this is almost within the norm, for in-line small cars this is definitely a lot. You must understand that any engine, even a completely new one, consumes oil. Actually, the engine oil simply burns away in the cylinders, remaining on their walls. This is its purpose - to cover all internal surfaces with a film and prevent dry friction. And this film burns in the chamber along with the fuel mixture.

The only question is how much oil is burned in your engine and whether you need to do something about it. The experience of many owners of used cars shows that even in a fairly worn-out engine, in most cases it is more profitable to simply add oil than to do a major overhaul.

In fact, there are slightly more reasons for increased oil consumption than, in the language of service station “specialists,” simply a “dead engine.” The engine oil can burn excessively, or it can also simply leak. And diagnosing the real cause of increased oil consumption in most engines is actually quite difficult. Moreover, some reasons are determined only by opening them, and therefore often after major repairs the craftsmen do not tell the owners exactly what the reason was in their case. And all because in many situations, engine overhaul is far from the most optimal way out of the situation.

Well, everything seems to be clear here - if the oil leaks, you need to change the gaskets, seals, and so on. Oil may leak from the engine in the following places (the most common problems):

Valve cover gasket. This is on top of the engine; in case of insufficient sealing, oil leaks are clearly visible on the outer side walls of the engine. As a rule, a lot of oil cannot escape through this gasket, but the tightness of the system must be restored in any case. Cylinder head gasket (cylinder head). Also in the upper part of the engine, under the cylinder head. This gasket (there are two of them in V-shaped engines, like the cylinder head) can be damaged in different places, as a result of which oil can leak out (the symptoms are the same as with the valve cover gasket), in addition, oil can leak into the system cooling, if that part of the gasket that is located between the working cylinders and the holes of the cooling system is broken. In this case, the engine will be externally dry, but the coolant will be cloudy and change color, and the oil in the engine will foam (foam can be seen on the inside surface of the filler cap through which oil is poured into the engine). This problem needs to be solved urgently, because it is dangerous to the life of the engine (due to coolant getting into the engine oil). Crankshaft and camshaft seals. Not on all engines such a leak can be seen by simply opening the hood. But there should be smudges from the bottom of the engine plus spots (puddles) of oil on the inner surface of the crankcase protection. This problem, just like any other leak, needs to be fixed as soon as possible. Oil pan gasket. This leak can only be seen on the lift and with the protection removed. Pay attention to this the next time you change the oil. Rear crankshaft oil seal (at the entrance to the gearbox). In most cases, this oil seal is changed only when the gearbox is removed, and it is impossible to see it. But again, a leak can be diagnosed by smudges in the lower part of the engine on the gearbox side. Gasket under the oil filter. Don't smile - it's actually not that uncommon. The question here is about the quality of the filter and its replacement. Replacing the gasket is quite simple. Burnt oil

Engine oil waste itself is quite easy to diagnose. When oil burns in the engine, it produces bluish smoke in the exhaust, which cannot happen when high-quality gasoline is burned (black smoke, as a rule, means that the injection is not working properly). In addition, if the engine burns oil over a long period of time beyond normal limits, an oily black edge forms on the edges of the exhaust pipe.

It is much more difficult to understand the cause of oil burnout. Without opening the engine, no one can definitely tell you the reason for the increased consumption of engine oil. But at the same time, there are a number of relatively inexpensive and uncomplicated ways to combat waste that can be tried before opening the engine.

First, you should note that oil burns in every engine! It simply cannot help but burn out completely, since it constantly forms an oil film on the internal surfaces of the working cylinders, where the fuel ignites. A much more important question is how much oil is burned in your engine and what is the burn rate for it.

The next important point is that the amount of oil burned directly depends on the operating mode of the engine. The more often the engine runs at high speeds, the more oil it will burn, and this has nothing to do with the condition of the engine itself. The laws of physics work here - the higher the speed, the higher the temperature of the engine and oil, respectively, the thinner the oil -> more oil remains in the working cylinders. Why does oil burn and how to deal with it?

Here are the main reasons why motor oil burns in the engine:

An oil that is not suitable for this engine has been filled in. For information on how to find out which oil is suitable for your engine, read the car's operating manual. In short and to the point, oil with too low a viscosity will simply sit in the cylinders and burn, while oil with too high a viscosity will form too thick a film on the inner walls. In both cases this will lead to increased oil consumption. The treatment method is simple - pour suitable oil into the engine. You'll be surprised how this can affect your engine oil consumption. In this case, from all the options allowed by the car manufacturer for a given engine, you should choose the oil whose viscosity is higher than what is currently filled. Switching from synthetic oil to semi-synthetic very often solves the problem of oil consumption. In this case, there is no harm to the engine, provided that semi-synthetics with these parameters do not contradict the recommendations of the car manufacturer. Worn valve seals (oil seals). In many engines, these seals can be replaced without even removing the cylinder head (cylinder head), and the price of this strategic spare part will surprise you with its insignificance. And oil consumption can decrease significantly. The problem can only be diagnosed indirectly by the compression values, but you will definitely understand everything only after replacement. The cause of wear on valve seals is temperature changes or unsuitable engine oil that is incompatible with the rubber from which they are made. Worn piston (oil scraper) rings. There's nothing you can do about it; ideally, the rings need to be replaced, and in most cases this results in a full engine overhaul. True, you can also try to do the so-called “decarbonization” of the rings (often helps cars after a long period of inactivity). The easiest way to “decarbonize” is to go out onto the highway and drive a dozen or two kilometers at significantly increased speeds, closer to the red zone on the tachometer. In addition, special chemicals for this are sold, which are added to the spark plug holes before “decarbonization,” but to be honest, the safety of such chemicals for the engine in the future is a big question. Damage or wear of the internal surfaces of the cylinders (wear-out), as well as other internal engine parts. Such problems simply cannot be solved and are usually accompanied by extraneous sounds when the engine is running. The cause of these malfunctions is the entry of dust and dirt into the engine, untimely replacement of oil and filters, low-quality oil, the use of foreign additives, and much more. It must be said that simply the age or mileage of the engine cannot cause an immediate increase in oil consumption; in this case, the consumption increases gradually and very slowly. The recipe in this case is to try to switch to a more viscous oil (from the one possible according to the engine manufacturer’s tolerances), change the valve seals and see what the oil consumption will be after that. If this is a few liters between changes, it is more profitable to simply add oil, while at the same time setting aside funds to replace the engine or car. A major overhaul in this case is a lottery with very little chance of success. High pressure of crankcase gases, or the turbine (compressor) has failed. In such cases, oil enters the cylinders directly through fuel injection from the crankcase ventilation system. High pressure of crankcase gases is typical for worn-out engines, and is a consequence of the reasons described above, but the turbine can be repaired or replaced. In addition, a faulty turbine (compressor) is fairly easy to diagnose.

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What motorists say about where engine oil goes

The influence of crankcase gases on the fact that oil leaves the engine . If you notice excessive oil consumption, check whether crankcase gases are escaping through the air filter, as well as the crankcase gas return pipes before and after the throttle valve. Perhaps this is the problem.
The condition of the seals affects lubricant consumption .
When valve seals become unusable, lubricant consumption will increase. If they become “stiff,” they will not be able to remove the lubricant, and it will burn. To fix the problem, it is recommended to disassemble the cylinder head. Replacing oil seals will cost 400 rubles, the cost of parts will be 100 rubles.
What is the consumption rate and how to understand that oil is leaving the engine .
When the consumption is 1,000 ml of lubricant per 1,000 km, it means there is an oil glutton. On my car, 2000 ml of oil is enough for 10,000 km. But a quiet driving mode is not for me. Lately I've been thinking that the engine needs to be repaired. It's not a matter of fuel or the fact that the "cats" are cut out. Imagine that the motor is a bath of lubricant with parts floating around. And when the oil leaves the engine, it means there is a malfunction. Perhaps the oil scraper rings or caps are worn out. In any case, the reason must be found.
Oil will still leak from the engine.
The fact is that mineral oil changes its lubricating properties after 6,000 kilometers. Synthetic after 10 thousand. Excessive oil consumption can occur for various reasons. For example, the gas pressure in the crankcase has increased, which is why some lubricant enters the combustion chamber as the piston moves to BDC.
Oil scraper rings are designed to remove lubricant from the cylinder walls while moving to bottom dead center, and when moving to top dead center, part of the lubricant enters the ducts of the compression rings. There they coke and the rings are deposited. The only thing that can help is to clean the crankcase ventilation system.

A few words about turbines

Engines with turbochargers have their own operating specifics, which can result in excessive oil consumption. Thus, old turbines were cooled by the engine lubrication system. Accordingly, if the turbine breaks during operation (bearings break), it can transfer oil from the engine through the bearings. Moreover, depending on how broken the turbine is, oil consumption can be quite large, up to 1...3 liters per 10 thousand kilometers.

Also, partial failure of the turbocharger can lead to an increase in crankcase gas pressure. And this in turn leads to oil entering the cylinders directly into the fuel injection through the crankcase ventilation system. In this case, it is necessary to inspect the turbine, repair it, and, if necessary, replace it.

We determine without disassembling

It is difficult to accurately determine the cause of increased oil consumption without proper diagnostics. The most common method - measuring compression - will not help here. It is effective when there is significant wear of the cylinder-piston group. And if the compression rings are in perfect order, and the oil scraper rings are stuck due to coking, the compression readings will remain high, but the engine will consume liters of oil.

One of the effective testing methods is vacuum. For this purpose, a cylinder pneumatic density analyzer is used, consisting of two vacuum gauges or one combo device. To check, the spark plugs are unscrewed and vacuum gauges are installed in each cylinder in turn. First, during the stroke of the piston, the maximum vacuum in the cylinder is determined - it is called full or useful. Based on this parameter, the diagnostician draws a conclusion about the wear of the cylinder liner.

Using a second vacuum gauge, the residual (parasitic) vacuum is determined. If the cylinder liner and valves are in good condition, its value characterizes the condition of the piston rings, or rather their degree of wear, the occurrence, and breakage of the bridges on the piston. If both parameters are normal, and oil consumption is increased, then the oil scraper rings are in order, and the likely cause of oil leakage is wear of the valve stem seals.

How to decarbonize?

Liquid compounds are poured into each cylinder of a warm engine through the spark plug hole. The purpose of the drug is to soften the carbon so that it later burns without the formation of solid particles that can damage the delicate ceramic honeycomb of the neutralizer. The liquid enters the piston bottom, passes through the gaps of the compression rings, and enters their grooves in the piston. Next - onto the oil scraper rings and into the engine sump. In this case, the piston bottom is best washed. Due to difficult access, cleaning of the grooves for compression rings is poor, and oil scraper rings are even worse to clean. Sometimes you have to repeat the treatment after a short mileage.

Taking these shortcomings into account, foam compositions were developed. The method of application is the same - through the spark plug hole in the block head. But unlike a liquid foam cleaner, it fills the entire cylinder and affects not only the piston bottom, but also the combustion chamber. And if the engine has direct injection, then the fuel injector nozzle will also be washed. In terms of efficiency, foam is better than liquid, since it keeps the active substance in suspension longer.

Sources

https://www.DriveNN.ru/journal/novosti/kuda-uhodit-maslo-iz-motora-i-kakim-dolzhen-byt-ego-normalnyy-rashod-id38177
https://auto.24tv.ua/ru/kuda_y_pochemu_ukhodyt_maslo_yz_dvyhatelia_avto_esly_uroven_upal_n7045
https://autoexpert174.ru/uhodit-maslo-dvigatelja-prichiny/
https://motoroilclub.ru/diagnostika-i-remont/uhodit-maslo-iz-dvigatelja.html
https://ProMotornoeMaslo.ru/pro-motornoe-maslo/kuda-uhodit-maslo-iz-dvigatelya/
https://KrutiMotor.ru/uhodit-maslo-iz-dvigatelya-prichiny/
https://www.dieselkraft.by/poleznaya-informatsiya/kuda-ukhodit-maslo-iz-dizelnogo-dvigatelya-12-veroyatnykh-prichin.html
https://rad-star.ru/pressroom/articles/maslo-ukhodit-iz-dvigetelya/
https://www.zr.ru/content/articles/925418-kak-pobedit-maslozhor-i-ego-posledstviya/