Why the engine is eating oil: possible causes

Sooner or later, car owners are faced with increased oil consumption in the engine. There are many reasons for this increased appetite. We must immediately say that for many modern cars some expense is still characteristic. But if it's too big, you should start diagnosing the motor. Consider the typical reasons why the engine is eating oil.

The main causes of increased consumption

As already noted, the admissible consumption is distinguished - this is oil in the fumes. Simply put, regardless of the type of ICE, it burns a small part of the lubricant during operation. The fact is that the lubricating fluid circulates in the system and falls on each element of the motor, including the walls of the cylinders. Each piston is equipped with special rings that collect the remains of lubricants from the walls of the combustion chamber into the crankcase. However, a small part still remains on the walls of the cylinders and burns together with a mixture of gasoline and air. Thus, the cost of lubricating fluid should be from 0.05% to 0.25% of the volume of burnt fuel. For example, if the motor used 100 liters. Gasoline, then the allowable consumption of lubricants should not be more than 25 g. However, this is the maximum figure. The minimum consumption is up to 5 g. This is the permissible limit. If there are deviations, then it is worth considering why the diesel engine is eating oil.

On new units, the lubricating fluid may not be consumed at all. But it happens so long as the engine is completely new. As the basic mechanisms wear out, this figure will increase. If the expense is frightening, you should look for the cause. And in order to eliminate it, it is necessary to disassemble the entire motor. Also, the reason can be simple, which is easy to eliminate. Further - about the basic malfunctions which lead to the increased consumption of grease.

Strong wear of oil rings

On the pistons of any ICE there are special oil-removable rings - one for each piston. They, as already noted, are needed to protect the cylinders from getting into them lubricants. Since the rings are in close contact with the walls of the combustion chamber, and at the same time it is associated with constant friction, they have the property of being erased. If there is wear, then the gaps will increase, through which the lubricating fluids will flow into the combustion chamber. There, the lubricant will burn safely with the fuel mixture, and then it will exit into the exhaust system in the form of smoke. This is the answer to the question why the engine is eating oil and smoke. Also, in the case of severe engine overheating, the rings can lie down - they lose their elasticity and are pressed in their seats to the pistons. Diagnose the problem by the characteristic blue smoke from the exhaust pipe. You can eliminate the breakage by replacing these same rings.

Worn cylinder walls

This is another popular reason why engine oil eats a lot. Here it freely flows in large volumes into the combustion chambers through the gaps, where it burns. You can also diagnose it by smoke. To eliminate the breakdown, major repairs are required with the boring of the cylinder block. But there is also an alternative solution to the issue - to acquire a new unit. But this is a more expensive option.

Leak through oil removable caps

The oil-removable cap is a special oil seal in the engine. It is made of special materials that easily withstand high temperatures. Due to severe wear, the stuffing box loses its elastic characteristics. As a result, the leakage and high costs of the lubricating fluid. To replace the caps, you only need to remove the cylinder head. It is not necessary to disassemble the entire engine. This is the least expensive in eliminating the reason why the engine is eating oil. This problem is often affected by engines from Subaru. Many owners of these cars complain about high consumption. Some write that this is a normal phenomenon and these engines actually have such a design (opposites). However, the frequent reason why an oil engine eats the Subaru ej20 is the oil-removable caps.

GBC gasket leaks

Such a defect is most often seen on cars with mileage. On the new, this does not happen at all - under production conditions the bolts are tightened very well. On machines with high mileage, where the wear of the motor is already large enough, the gasket simply burns out. This happens often enough. A gasket replacement is required to correct the problem. To do this, simply remove the cylinder head. After the new one is installed, it is recommended to tighten the bolts evenly, so that the leak does not form again.

Crankshaft Oil Seals

In the case of severe wear, low temperatures or filling in the engine of poor quality oils, the oil seals often squeezes out, which causes a high flow rate. The cost of a new oil seal is minimal, but the amount of replacement work is very large.

Turbine rotor on supercharged engines

If the car is equipped with a turbocharger, then leaks can grow significantly. It is possible to dry the oil system in a very short period if wear of the bushing on the turbine rotor is observed. When the motor began to work differently, the first thing to check is the correct functioning of the rotor.

Frequent faults

The lubricant flows through the oil filter. One of the characteristic signs - stains and stains under the car after parking. The cause of the leakage is a weak tightening of the filter housing. You can easily get out of this situation - tighten the filter more tightly. This will instantly eliminate the leak. Also, motorists are faced with a leak through the cylinder head cover. In most models of auto it is fixed to 6-12 bolts. Some of them may simply not be pulled. To the raised expense also lead also oils of poor quality. The fact is that when lubricants get on the piston, they instantly burn. It is recommended to fill a higher quality product and then the expense will come back to normal.

Style of riding

Not all people go quietly. With more aggressive driving styles, when the engine is gaining momentum until cut-off, do not forget that this is an extreme mode and increased oil consumption. In that case, this is a common thing.

Seasonality

Another factor is the time of the year. So, the winter consumption is higher, as the car works in severe frosts. Professional auto mechanics recommend for severe winters to use higher quality oils with lower viscosity - then with the expense everything will be in order.

Diesel engines

We examined gasoline engines, and now we will analyze why the diesel engine is eating oil. A large consumption, if 1 l of lubricants goes for 10 000 km. The causes of oil consumption in diesel engines are generally the same as in the case of gasoline. Grease can flow through the crankshaft oil seal. Also, leaks go through the cylinder head gasket or oil-reflecting caps. It is recommended to check the injection pump. In 25% of such cases, the problem is precisely in it. Failures of injection pump are different. In one case, you can do repairs, in another - you need a replacement. Among the reasons why the engine uses an oil on KamAZ, you can single out a long work in the idle mode. Also, leaks are often observed through the turbocharger lubrication system - to eliminate tightening the connections in the turbocharger system or changing the gaskets. Even a high flow leads to a clogged air cleaner and air intake. This can easily be eliminated by cleaning it.

Opposite engine

The designs of modern opposing engines are such that, even in their new condition, they will expend more lubricants than their usual counterparts. The manufacturers themselves, for example Subaru, say that the normal consumption for the opposing engine is 1 liter for 2000-2500 km. Among the reasons why the opposing engine is eating oil, there may also be rings, caps, leaks. Engine diagnostics are required.

Increased appetite after overhaul

It also happens that a completely renovated engine does not please its owner. To understand the reasons, it is necessary to understand what kind of repair was done. Perhaps, the pistons did not change, and only the replacement of the rings was carried out - they will be worked on for long oval pistons. In fact, the reasons why after a major overhaul engine is eating oil, very much. And in order to find a malfunction, it's best to disassemble the motor and inspect it. But this is recommended only for professionals.

Conclusion

We examined the main reasons why the engine is eating oil. This information should help novice motorists in the diagnosis of their cars.