How do oil filters work

Motor oil is a vital component to the health and longevity of your engine. It is responsible for keeping the engine clean and its moving parts lubricated. If the oil is dirty, tiny particles can wear down the surfaces of the engine and potentially cause some serious damage. That is why vehicles are equipped with an oil filter.

Oil filters have two main functions. They are responsible for removing contaminants from the engine oil that can build up over time, and they keep the oil where it needs to be at the time it needs to be there.

Waste Filter

Mechanics often refer to oil as the lifeblood of your vehicle. You can think of the oil filter as the kidneys. Our kidneys filter waste from our blood and regulate our salt and water balance, helping us to remain healthy. If they fail, waste products and water can build up in our body, leading to potentially life-threatening complications.

Like the kidneys, your oil filter removes harmful waste. It keeps your engine running smoothly by catching harmful dirt, debris, and metal fragments in the oil. Without the filter, these particles can reach vulnerable engine components and cause damage. When the junk is filtered out, the oil stays cleaner longer, bettering the performance of your engine.

Keeping Oil in the Right Place at the Right Time

Beyond keeping the oil clean, the parts of the filter work together to keep the oil clean and help to send it to the proper place at the proper time.

Parts of the filter:

  • Tapping plate. Motor oil enters and exits the filter through the tapping plate. The tapping plate consists of a large center hole surrounded by smaller holes. The oil goes in through the smaller holes and then through the filter material and then exits into your engine through the large center hole. 
  • Oil filter material. The material that catches the debris in the oil is made up of a combination of synthetic fibers. It is folded into pleats, creating a larger surface area.
  • Anti-drain back valve. This valve closes to keep oil from making its way back into the oil filter from the engine when the vehicle is shut off.
  • Relief valve. Oil thickens when it is cold outside, which makes it difficult to move through the filter material. To make up for this, the relief valve will discharge a minimal amount of unfiltered oil to lubricate the engine until it warms.
  • End discs. These discs are on the end of either side of the filter and are made of either fiber or metal. They keep the oil that hasn’t been filtered from entering the engine.

You needn’t remember all these parts but understanding how they work together shows you how important it is to maintain regular oil and oil filter changes.

Replace the Filter Regularly

As you use your vehicle, the filter gets dirtier, and will not function as effectively. This means that there will come a time that the filter needs to be replaced.

Your vehicle owner’s manual is your best source for telling you how often oil filter changes should be performed on your vehicle. For most modern vehicles the average amount of time is every five or six thousand miles.

If you are changing your filter at the appropriate intervals, you are less likely to experience any negative effects, however, if you put it off too long you may notice the following symptoms:

  • Low oil pressure
  • Change in exhaust color
  • Acceleration trouble
  • Metallic type noise under the hood

Trust Meridian Automotive

At Meridian Automotive, every oil change service includes an oil filter replacement.

During your oil change service, our highly skilled technicians will drain out the old oil and replace the oil filter, then add clean, factory recommended oil to your vehicle. We will also adjust your tire pressure if needed, and inspect all fluid levels, air filters, and wiper blades. Call 208-888-3797 or schedule an appointment online.

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