Engine oil performs very important functions. It creates a film on the surface of the parts to prevent their wear, removes heat from the moving elements, and protects them from corrosion. In addition, it cleans the engine. Lack of lubricant is dangerous for the motor. In this article, we look at why leaks may occur, tell you where to look for the fault, and find out whether a car leaking oil is safe to drive.
Why is my car leaking oil?The most common causes of oil leaks are:
Gaskets, seals, and O-rings are usually made of rubber, which over time loses its durability and becomes less elastic. As a result, the car starts leaking oil in the area of the mating surfaces sealed by these elements.
Increased pressure in the system
Accumulation of dirt and impurities can reduce the throughput capacity of individual sections of the lubrication system, which leads to a local increase of pressure. This may also be the result of clogging of the crankcase ventilation components, which leads to exhaust gases getting into the lubrication system. As a result, oil is squeezed out through seals and joints. Sometimes the problem is caused by an excessive amount of lubricant, and its high viscosity.
- Measure the pressure in the lubrication system using a pressure gauge. If it’s higher than normal, proceed to the next step.
- Remember when you last changed the oil. If the vehicle has covered about 15,000 km since then, replace the lubricant and the oil filter.
- Make sure you use the product with the viscosity recommended by the manufacturer. Higher viscosity may increase the pressure.
- Flush the lubrication system. To do this, pour a special additive into the oil filler neck, start the engine and let it idle for a while. After that, drain the fluid, replace the filter and pour in the new oil.
- Check the oil level. If it exceeds the level prescribed, remove the excess amount using a special vacuum extractor, or drain it through the drain plug.
- Remove and inspect the pressure relief valve. Clean it of dirt. Check if the locking mechanism moves freely. If it’s seized up, replace the valve or the entire pump assembly.
- Warm up the engine to operating temperature. Remove the oil filler cap and cover the hole with your hand. Ask an assistant to press the accelerator pedal several times to increase the engine speed to 2,000–2,500 rpm. If you feel pressure increase in the system as the car revs up, then the crankcase ventilation system is faulty. Bring your car to a garage to have it repaired. The specialists there will clean the components, and, if necessary, replace the PCV valve and oil catch can.
Improper tightening of bolts and an incorrect tightening sequence can cause warping or cracking of the gasket. In addition, using sealants and adhesives to try to fix the seal can damage it.
This can be caused by the ingress of foreign objects, or hitting an obstacle, which the oil pan is most vulnerable to.
- Seal the crack by means of cold welding.
- Take your car to a garage to have the oil pan welded.
- Install an oil pan guard. If you often drive off-road or use your vehicle on poor quality roads, this will help you avoid a lot of problems.
As a result of driving on poor-quality roads and excessive vibrations of the car due to, for example, worn suspension components, some fasteners can become loose. You may find the car is leaking oil from under them.
Why a car leaking oil is dangerous
Due to the lack of lubricant, wear of mating parts increases. First of all, this adversely affects the condition of the valve stem seals, which further exacerbates the problem. The oil, already at too low a level, gets into the engine cylinders and burns there. The further lack of lubrication leads to the destruction and seizure of the camshaft and crankshaft, as well as of the engine pistons. In some cases, the connecting rods may break as a result of overheating.
In addition, if your car is leaking oil, the engine block itself gets contaminated, and dirt accumulates on it. This compromises the heat exchange processes, increases the load on the engine, and can cause it to overheat. The lubricant can accumulate in spark plug wells, which causes malfunctions in the ignition system. In addition, oil can destroy the insulation of wires under the bonnet, and clutch elements; it also can soften rubber mounts, seals, and interfere with plastic parts.
The service life of an engine directly depends on the lubricant level. Therefore, any leaks are dangerous. They should be fixed as soon as they are detected. After all, repairing a car that is leaking oil is always cheaper than overhauling or replacing the engine.