The oil filter prevents contaminants from entering the engine oil without disrupting the lubricating process, ensuring perfect oil circulation in engines. Oil filters are applicable in different types of hydraulic machinery.
Internal combustion engines, both on- and off-road motor vehicles, use this device. The great importance of oil filters in modern combustion engines is that they allow first-class lubrication for seamless operation.
An effective oil filter is crucial for an engine because it prevents damage from dirt particles, soot, or unburned fuel in the oil. Today you’ll get to know the definition, functions, parts, types, working principle, diagram, and symptoms of a bad oil filter.
In this reading, we’ll learn what an oil filter is, its diagram, functions, parts, types, and how it works.
Let’s begin!
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What Is an Oil Filter?
An oil filter is a mechanical device that removes contaminants, dirt, and unburned fuel from circulating. The component allows only fresh oil to circulate into the engine while trapping dirt. For this reason, it’s necessary to treat or replace the oil filter periodically.
Oil filters are made for filtering impurities from hydraulic, lubricating, transmission, or motor oil. Internal combustion engines for both on- and off-road motor vehicles, powered airplanes, railroad locomotives, ships, and boats, as well as static engines like generators and pumps, are their main applications.
Other vehicle hydraulic systems, like automatic transmissions and power steering, utilize an oil filter. Gas turbine engines, such as jets, also use oil filters.
In short, the filter is used on cars, trucks, motorcycles, boats, airplanes, tractors, etc. They all use the component for purifying oil and removing dirt from it before it circulates.
Oil filters are also necessary for gas turbine engines, such as those seen in jet airplanes. Many different kinds of hydraulic machinery need oil filters. The oil industry itself uses filters for oil recycling, pumping, and manufacturing. These days, most engine oil filters are either “bypass” or “full-flow” (inline).
Functions Of Oil Filters
Oil filters play a crucial role in maintaining engine health and performance. Here are the primary functions of oil filters:
- Engines provide dirt particles and combustion residues such as dust, metal debris, oil carbons, etc. oil filers collect these particles from the oil before it enters the engine. The oil filter cleans the engine oil, as consistent engine performance depends on clean oil.
- Soot gets into the oil and soil and thickens it. Oil filters consist of several thinning holes that keep thick oil from the pump from getting into the engine.
- All moving parts, such as connecting rods, camshafts, and valvetrains, are protected from wear and damage if the filter functions well.
- An oil filter is frequently a part of other car hydraulic systems, such as those in power steering and automatic gearboxes.
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Major Parts of Oil Filters
Oil filters consist of several key components that work together to ensure effective filtration. Here are the major parts:
Tapping Plate
A tapping plate is an entry and exit point on the oil filter. It contains small holes around the edge, which allow the free flow of oil into the filter container. The threaded hole at the center is where the oil flows out and it faces the engine.
Antidrainback Valve
The oil filter part is a rubber valve with a flap that holds oil from flowing back into the filter when the engine is not running. The filter required this because it’s located toward the middle or bottom of an engine.
Filter Medium
A porous filter medium contains microscopic cellulose fibers and synthetic fibers such as polyester and glass. It enhances the durability and efficiency of the filtering process. Additionally, resin saturation provides stiffness and strength. high-performance filters are designed with more synthetic fibers.
Pleats
The folded filter medium creates a greater total surface area. The thickness of the medium determines the number of pleats.
Center Steel Tube
This oil filter part provides structure to the filter and allows filtered oil to return to the engine. The holes’ number, size, and position will ensure that the oil flow remains effective and unrestricted.
Relief Valve
On a cold start, oil can be too thick to filter, so we need to prevent the engine from starving. A relief valve in an oil filter opens when sufficient pressure pushes the calibrated spring downward. This allows unfiltered oil into the center tube through the top.
End Disc
An end disc, which is made of either fiber or metal, is used to stop the unfiltered oil from leaking into the center tube. This end disc is bonded to each end of the filter medium.
Retainer
A retainer is a bit of metal that acts as a leaf spring. It keeps the filter medium and end disc tight against the tapping plate.
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Diagram Of An Oil Filter
Types of Oil Filters
There are several types of oil filters, each designed for specific applications and needs. Here are the main types:
Full-Flow Oil Filter
The full-flow oil filter is the most common type used on cars, which is also known as a primary oil filter. Its purpose is to purify and eliminate impurities from all of the engine’s oil.
Full-flow filters are specifically designed to work in colder temperatures; cold weather causes motor oil to thicken, and the oil is thick during a cold start.
These filter types allow the oil to move more freely through the engine than other types. If a filter is too restrictive, the engine may be starved of oil, which may cause damage to its parts. This is why the full-flow filter is better, as it provides sufficient oil needed for the efficient performance of the engine.
Cartridge Oil Filter
The cartridge is a type of full-flow oil filter that is less complex and easy to use. It’s mounted upright, which makes it easily accessible for inspection without needing to remove the oil. These filter types are available in both metal and fiber, but in most cases fiber, which makes it easier to recycle.
Spin-On Oil Filter
A spin-on filter is another type of full-flow oil filter that contains a steel canister with a paper element. Car owners can easily fix it themselves since the installation is simple and it requires minimal tools.
Secondary or By-pass Oil Filter
Some automobiles use secondary oil filters to supplement full-flow filters. The design aims to purify less than 10% of the engine oil. The secondary oil filter will then clear off any contaminants that a full-flow filter wasn’t able to remove. These filter types extend the life of motor oil and ensure additional protection for the engine.
Spinner Oil Filter
A spinner oil is a type of secondary oil filter that uses centrifugal force to trap contaminants from the engine oil. Some of the filters can generate more than 2,000 force, which is greater than that of gravity. These filter types have the possibility of removing the tiniest contaminants from the motor oil.
Magnetic Oil Filter
Just like the spinner oil filter, a magnetic oil filter is also a type of secondary filter that supports the full-flow version. The design effectively removes metallic contaminants from the motor oil, but it does not clean dust and grime. Magnetic oil filters don’t need replacement like the other types. All it needs is regular cleaning to keep it functioning.
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How An Oil Filter Works
The early-production engines did not use oil filters and were even installed with poor-quality oil, which caused frequent oil changes. The development of the first full-flow oil filtration system solved the problem. Conventionally, oil flows through the filter before reaching the moving components inside the engine.
The working of oil filters is simple and straightforward to understand as oil enters the device through a series of small holes on the outer edge base flange. The oil then moves through the filter for cleaning, which eventually returns to the engine through a larger center hole.
Nowadays, most filters come with an anti-drain-back valve, typically in the form of a rubber membrane. This part is often located at the perimeter holes in the base flange.
The membrane opens as oil enters the filter case under pressure. When the engine is at rest, this membrane closes the holes. The system valves maintain oil within the filter and prevent engine dry starts; that’s for an engine to start with no oil.
Modern internal combustion engines incorporate a bypass filter, also referred to as a secondary oil filter. They protect the engine from starvation under certain situations, i.e., in very cold weather that causes oil to be thick, bypass oil filters allow such oil to easily pass through it.
Oil can also bypass the filter when the filter is plugged in. This occurs when the engine, even with a full-flow filter, fails to filter the oil.
Symptoms Of Bad Oil Filter
A bad oil filter can lead to various symptoms that indicate potential issues with your engine’s lubrication system. Here are some common signs:
Bad Engine Performance
When an oil filter is not in excellent condition, the performance level of the engine will drop dramatically. One will notice that the engine struggles to pick up speed, unlike its performance under normal conditions.
The accelerator will act like it’s not working properly. Serious care should be taken if any of these symptoms occur or else damage will be caused to the essential part of the vehicle.
Sputtering
A clogged oil filter causes sputtering in a vehicle. it happens when the oil filter is unable to release oil as it should, which causes the car not to keep up with the speed you deserve. Light sputtering could lead to a bigger problem.
Metallic Sounds
A faulty oil filter can cause oil starvation in the engine, and when this happens, metals will grind against each other. The occurrence of metallic sounds when the engine is running is a sign that something is wrong with the oil flow. Those who hear such sounds should promptly address the issue to prevent further damage to the vehicle.
Dropping Pressure
One can read the oil pressure gauge from the vehicle’s dashboard to ensure the pressure is not dropping. Examine the problem if you notice a steep drop in oil pressure. Naturally, engine oil pressure will not drop more than a fraction of a percent while driving. A significant change in pressure, therefore, indicates an oil flow error.
Dirty Exhaust
A A clogged oil filter can result in your car emitting black or dirty exhaust. Users will often smell oil burning as it passes into the exhaust pipe. The smell indicates a malfunctioning filter, necessitating immediate replacement to prevent further damage.
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Conclusion
An oil filter is a crucial component in maintaining an engine’s health by removing dirt, debris, and contaminants from the engine oil before it circulates through the engine. Clean oil ensures better lubrication, reduces wear and tear, and extends the life of both the engine and the oil itself.
Regular oil filter replacement is essential for keeping the engine running smoothly and efficiently. Whether in daily-driven cars or high-performance vehicles, a properly functioning oil filter plays a major role in ensuring long-term engine reliability.
FAQs on Oil Filter
What is the purpose of an oil filter?
An oil filter removes contaminants and particles from the engine oil, helping to protect the engine’s moving parts and maintain performance.
How often should an oil filter be changed?
Depending on the vehicle and oil type, you should typically change the oil filter every 3,000 to 7,500 miles.
What happens if I don’t change my oil filter?
A clogged or dirty oil filter can restrict oil flow, reduce lubrication, cause overheating, and lead to serious engine damage.
Are there different types of oil filters?
Yes. Common types include mechanical, magnetic, cartridge, and spin-on filters, each designed for specific applications and performance levels.
Can I reuse an old oil filter?
No. Oil filters are designed for single use and should be replaced whenever the oil is changed to ensure optimal engine protection.
How do I know if my oil filter is bad?
Symptoms include low oil pressure, dirty exhaust smoke, metallic noises from the engine, and dirty or thickened oil.