We can identify three fundamental causes if the dipstick on our car indicates that oil is leaking. They range in severity from one to the other.
When we turn on our car’s ignition, oil starts to flow inside the internal combustion engine to lubricate all moving parts and ensure efficient, dependable, and smooth functioning.
As we already know, ensuring the engine has enough oil prevents overheating, major failure, and premature deterioration of the internal parts.
“Impurities in the oil and fuel might cause the PCV valve to clog over time.”
For this, we have the oil dipstick, which has a ring on top of the engine and extends to the crankcase at the bottom.
It is there that the oil is stored, and to get an accurate reading, we need to measure it while the engine is cold, the car is on a flat surface, and all the oil has drained to the bottom.
But what occurs if oil seeps from the dipstick line and stains the engine’s top? We will examine the three potential reasons for this issue, going from the least significant to the most catastrophic.
Improperly positioned dipstick
Mechanical issues can occasionally be brought on by circumstances that are relatively easy to handle. This is the first instance of a probable oil leak coming from the dipstick because if the upper portion of the conduit, which serves as a plug, is not positioned correctly, some oil may leak out.
The only thing left to do in this situation is to install it appropriately or replace it if the piece has deteriorated or been distorted and does not fit.
To relieve the pressure in the crankcase caused by the piston drive and the rise in engine temperature, the PCV valve, also known as the Positive Crankcase Ventilation Valve, is used.
The oil and hydrocarbon fumes produced in the crankcase can thus flow via the PCV valve and be discharged into the intake manifold.
The vapors will re-enter the combustion chamber and become a component of the air-fuel mixture.
This enables the crankcase pressure to decrease, lowering the risk of breakdowns and stopping the release of more polluting gases.
The key is that the PCV valve only permits vapors to travel from the crankcase to the intake manifold in one direction. It is a non-return valve, to put it another way.
But because of the impurities in the oil and fuel, it can clog over time and needs to be replaced or cleaned regularly (approximately every two or three oil changes).
If this is not done, it will eventually clog, and the crankcase pressure will increase, potentially leading to failures such as cylinder head or crankcase gasket rupture, or air filter clogging.
Yes, severe pressure can also force oil to the dipstick line, where it can easily escape.
Loss of compression
An engine’s compression ratio is essential for the combustion process to occur. This measurement establishes the cylinder’s compression capacity, but if it declines, performance will also.
A cylinder’s compression typically declines because the cylinder seal has partially failed, leading to a leak toward the crankcase.
As was previously noted, the engine oil is stored in the crankcase, and the PCV valve releases the extra pressure created in the crankcase by the vapors produced by the heating of the lubricant and the fuel, which always escape from inside the cylinder in minute quantities.
However, if the compression decreases, it is because of a sealing issue. One of the possible causes of this issue is that a ring, which encircles the piston and serves as a gasket to maintain the cylinder’s seal, may be destroyed.
Loss of compression results in a rise in crankcase pressure when the ring fails. Oil from the crankcase may spew out via the oil dipstick line if the PCV valve cannot counteract this pressure rise.
This issue is unquestionably the most significant and expensive to fix and might necessitate replacing the engine altogether.
Do you need to know how to identify a compression issue and its potential causes? Don’t forget to read our essay on the topic.