Engines That Eat Oil: What Happens to the Oil That Disappears From the Engine?

It's impossible not to hear about cars that have oil-eating engines. I have heard of some cases in which the driver put 1 liter of oil for every 1000 km traveled. In general, almost all engines eat oil, but some only 50 ml per 10,000 kilometers, others even quantities measured in liters. But where does all this oil go?

Even though we hear more about diesel engines that they consume oil, in general almost all engines, regardless of fuel type, consume oil.

Some drivers can swear by heart that their car does not consume a gram of oil, but in reality, absolutely all engines consume oil, which is true, in different quantities.

Today's manufacturers even announce a new consumption of oil on new cars, meaning they do not claim that the engines do not consume, they even give as normal consumption of 1 liter of oil for every 10,000 kilometers traveled.

If you had the impression before that the oil is only for lubrication and is not consumed, you may be in for a surprise. If at each oil change the level on the dipstick remains the same, it means that very little oil has been consumed, a maximum of 200 ml.

This is a normal and happy situation, which signals that the engine is running in parameters and has no problems. But what do we do when our engine consumes 1 liter per 1000 kilometers or even more? What do we do if we put oil in and the light comes on every month to add?

When the oil disappears from the engine very quickly, it means that we have some problems. Below are the main causes of oil consumption.

Worn segments - blue smoke

The role of the engine segments is to insulate the flue gas from the lubrication system. If the engine segments are worn, the oil will pass through them and enter the combustion chamber, where it will be burned together with gasoline or diesel and will end up in the exhaust, where it will be removed in the form of blue smoke.

We know if the engine suffers from this problem when our car emits smoke all the time, especially at high speed, whether the engine is cold or hot.

Valve oil seals - blue smoke

Another situation may be that our car emits blue smoke on the exhaust only when the engine starts and when it is cold.

This can be caused by worn valve seals. The valves are also lubricated with oil, but the oil is insulated from the combustion chamber by some oil seals that do not allow the oil in the cylinder head to reach the cylinders. If the oil seals are worn and have a large play, the oil enters and is burned, just like in the case of worn segments.

Turbocharger leak - blue smoke

The most common problem with modern turbine cars is this. That is, a turbocharger that cools with oil, but which begins to have a large play in the central axis and the oil begins to flow past the seals, reaching either the inlet or the outlet. In both cases, the oil leaks and is burned, eliminating blue smoke on the exhaust. This problem is often encountered in new generation cars, either turbo-diesel or TSI type.

Using too thin an oil - blue smoke

If, in any case, you put other oil in the engine than the one indicated, with lower viscosity, that oil will slip much easier next to the parts listed above, ie segments, valves, turbine shaft, even if the parts are not worn. He will be evacuated where he will be burned and we wake up with blue smoke on the final drum.

We must not confuse blue smoke with white or black smoke. The blue smoke, which is a light blue, is caused only by the burning of the oil. That is, if we emit white smoke on the exhaust, it is clear that our engine is consuming oil. White smoke is caused by the wrong combustion of fuel, ie problems with the injectors, the injection pump, or the burning of antifreeze.

In turn, black smoke is caused by burning too much diesel in diesel cars. That is, we have too rich a mixture caused by a blocked air filter, problems with the injection pump, turbocharger, valves, or EGR valve.

Therefore, the engine of a car, regardless of its technology, no matter who produces it or how expensive it is, cannot be made completely sealed, without any margin of play between the parts, which makes the lubrication not 100% efficient.

An internal combustion engine with optimum lubrication has not yet been invented. So, the oil ends up being burned and consumed in its lubrication process. But this is normal!