Top 3 Reasons Engine Oil Gets in the Air Filter

The air filter is intended to capture scrap, dirt, and different contaminants — however not oil. often, once an area service mechanic replaces an air filter, the technician can indicate that engine oil has been found; either within the filter housing or embedded within the used filter. whereas oil finding its way into the filter isn't generally an indication of engine breakdown, it ought to positively not be neglected. Let’s examine the highest three reasons oil finds its way into the filter within the 1st place.

1. A Clogged Positive Crankcase Ventilation (PCV) Valve
The PCV valve is connected to an air intake housing via an often-rubber vacuum hose used to give a vacuum release within the engine’s housing. This element is usually installed on top of a cylinder head valve cover, wherever pressure flows from the engine’s bottom half, through the cylinder heads, and exits into the air intake. The PCV valve is comparable to an engine filter in this it eventually becomes clogged with excessive scrap (in this case — engine oil) and will get replaced as counseled by your vehicle’s manufacturer. If the PCV valve isn't replaced as counseled, excessive oil can blow through the PCV valve and enter the air intake system.

What’s the solution? If it's determined that a clogged PCV valve is that the supply of engine oil within your filter or air intake system, it ought to get replaced, the air intake ought to be cleansed, and a replacement filter ought to be put in.

2. Worn Piston Rings
A second potential supply of engine oil leaky into the filter housing is because of worn piston rings. The piston rings square measure put in on the outer reaches of the pistons within the combustion chamber. The rings square measure meant to form a combustion ratio and allow little amounts of engine oil to continue lubricating the inner combustion chamber throughout every piston stroke. once rings wear out, they loosen and may cause oil ‘blow-by’ — typically displayed by blue smoke returning from the car’s pipage while driving. The early stages of worn piston rings, excessive oil blow-by will cause excessive pressure to biuld in the housing, that sends additional oil through the PCV valve and eventually into the air intake, as explained above.

What’s the solution? If you notice engine oil within the filter or intake housing, an expert mechanic may advocate a compression test. This is where a mechanic can install a compression gauge on every individual sparking plug hole to envision the compression of every cylinder. If the compression is not up to it ought to be, worn piston rings are usually the culprit. sadly, this repair isn't as straightforward as replacement a PCV valve. If worn piston rings square measure determined because the supply, it'd be an honest plan to start out looking for a replacement vehicle, as replacement pistons and rings can probably price over the worth of the vehicle.

3. Clogged Oil Passages
The final potential reason engine oil can find its way into the air intake system and eventually clog the filter is because of clogged oil passages. This symptom typically happens once the engine oil and filter haven't been replaced as counseled. it's caused by excessive carbon deposits or engine sludge developing within the housing. once the oil doesn't flow expeditiously, excessive engine pressure level are created and cause additional oil to erupt the PCV valve and into the air intake.

What’s the solution? In this instance, sometimes changing the engine oil, filter, PCV valve, and replacing the dirty air filter is good enough. However, if clogged oil galleys are discovered, it is usually recommended to flush the engine oil and replace the oil filter at least twice within the first 1,000 miles to ensure the engine’s oil galleys are clear of debris.