Increased oil consumption is a common headache for car owners, especially those whose cars already have a decent mileage. The engine starts consuming lubricant faster than it should, and you have to top it up regularly. Let's look at what factors lead to such an "oil appetite" and what can be done to reduce engine oil consumption, extending its service life and increasing reliability.

Why the engine starts consuming oil

Before looking for a solution, it is worth understanding the root causes. Usually one of the following factors is to blame:
  1. Wear of the cylinder-piston group. Over time, piston rings and cylinder walls wear out, lose their seal, and lubricant penetrates into the combustion chamber.
  2. Dried-out valve stem seals. These seals harden and crack over time, no longer removing oil from the valve stem, causing it to enter the cylinder.
  3. Clogged crankcase ventilation. If the ventilation valve is clogged, the pressure inside the crankcase rises, forcing oil out through seals and gaskets.
  4. Leaks through gaskets and seals. On older cars, these are often the cause of a slow but constant drop in oil level.
  5. Incorrectly selected oil. A too thin or low-quality product cannot stay on parts and simply burns off at operating temperatures.

Effective methods to combat excessive consumption

There are several effective approaches that can reduce oil loss without resorting to a major overhaul.

1. Choosing oil by viscosity

If wear is already present, you can try switching to a more viscous oil. For example, replace 5W-30 with 5W-40 or 10W-40. Such a lubricant creates a thicker film that holds better in the gaps. However, you should always check the vehicle's owner's manual.

2. Monitoring the level and condition of the lubricant

It is necessary to regularly check the oil level with the dipstick. If it quickly darkens or becomes thick, this is a reason to be wary. You also must not skip the scheduled oil change intervals specified by the manufacturer.

3. Replacing valve stem seals

The operation is not too costly, but it is often this that gives the main effect for reducing engine oil consumption. Fresh seals block lubricant from entering the cylinders, which reduces exhaust smoke and unpleasant odor.

4. Inspecting the crankcase ventilation system

The PCV valve or its analogues must freely pass crankcase gases. Clogging of the system leads to increased pressure and, as a result, oil being forced out through weak points. The valve needs to be cleaned or replaced.

5. Using special additives

There are compounds on the market that partially restore the elasticity of seals and stabilize oil viscosity under load. They will not radically solve the problem, but they can temporarily reduce oil burn-off, which is especially relevant for old engines.

6. Checking the tightness of seals and gaskets

It is necessary to periodically inspect the oil pan and engine joints for oil leaks. Even a small drip can result in the loss of hundreds of milliliters of lubricant per thousand kilometers.

7. Comprehensive diagnostics of the power unit

If consumption exceeds one liter per thousand kilometers, it is necessary to check compression in the cylinders and perform a leak-down test. This approach will show wear of rings or valves. Sometimes it is enough to replace the rings or lap the valves to bring consumption back to normal.

Practical example: reducing oil consumption on Ford Focus 2

For the Ford Focus 2, this problem is quite typical, especially for gasoline engines 1.6 and 2.0 of the Duratec series. Most often, the culprits are coked piston rings and worn valve stem seals.
To reduce oil consumption on Ford Focus 2, in practice the following are used:
  • flushing the engine with special decarbonizing compounds;
  • replacing valve stem seals;
  • using oil with a viscosity of at least 5W-40;
  • regular cleaning of the crankcase ventilation system.
As a rule, such a set of measures can reduce oil consumption by 2-3 times.

Conclusion

Increased oil burn-off is not necessarily a death sentence for the engine. The problem can be dealt with using relatively simple methods: choose the right oil, replace the seals, eliminate leaks, or clean the ventilation. If the situation is serious, then detailed diagnostics and subsequent repair are unavoidable. The main thing is to notice the first symptoms of excessive consumption in time, because the condition of the oil directly affects the durability of the engine and the reliability of the entire vehicle.