With a perfect circulation of oil in engines, the oil filter is featured to prevent contaminants from the engine oil without interrupting the lubricating process. Oil filters are applicable in different types of hydraulic machinery. The device is used in internal combustion engines, both on- and off-road motor vehicles. The great importance of oil filters in modern combustion engines is that 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 get started!
What Is an Oil Filter?
An oil filter is a mechanical device that removes contaminants, dirt, and unburned fuel from circulating. The component allows just the circulation of fresh oil into the engine and it keeps the dirt. This is why the oil filter needs to be treated or changed within some period of time.
An oil filter is used on other vehicle hydraulic systems, such as automatic transmissions and power steering. Gas turbine engines, such as jet, also use oil filters. In short, the filter is used on a car, trucks, motorcycles, boats, aeroplanes, tractors, etc. They all use the component for purifying oil and removing dirt from the oil before circulating.
Diagram Of An Oil Filter
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 entering 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 avoid thick oil from the pump into the engine.
- All moving parts, such as connecting rods, camshafts, and valvetrains, are protected from wear and damage if the filter functions well.
Related: What Is Oil Pump? Its Types and How it Works
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 centre 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 fibres and synthetic fibres such as polyester and glass. it helps to increase filtering durability and efficiency. It’s also saturated with resin to offer stiffness and strength. high-performance filters are designed with more synthetic fibres.
Pleats
The folded filter medium creates a greater total surface area. Well, the thickness of the medium will determine how many pleats there are.
Center Steel Tube
This oil filter part provides structure to the filter and allows filtered oil to return to the engine. The number, size, and position of holes will ensure the effectiveness of the oil flow and not be restricted.
Relief Valve
Because oil can be too thick to filter on a cold start, the engine needs to be prevented from starving. An oil filter is designed with a relief valve that opens when enough pressure is produced to force the calibrated spring downward. This allows unfiltered oil into the centre tube through the top.
End Disc
An end disc, which is made of either fibre or metal, is used to stop the unfiltered oil from leaking into the centre 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.
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 with oil, which may cause damage to its part. 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
In some automobiles, secondary oil filters are used to support vehicles with full-flow filters. It’s designed 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. It is designed to effectively remove metallic contaminants from the motor oil but 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.
Related: What Is An Oil Cooler? Its Function And How It Works
How An Oil Filter Works
The early-production engines did not use oil filters and are even installed with poor-quality oil, which causes frequent oil changes. When the invention of the first full-flow oil filtration system was developed, the problem was solved. Conventionally, oil flows through the filter before reaching the moving components inside the engine.
The working of oil filters is simple and easy 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 then eventually returns to the engine through a larger centre hole.
Most filters nowadays are designed with an anti-drain-back valve, mostly 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 are incorporated with a bypass filter, also known 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 filter allow such oil to easily pass through it. Oil can also bypass the filter when the filter is plugged in. This is because oil is sometimes not filtered, even when a full-flow filter is available in the engine.
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
Unlike the working of the engine when an oil filter is in good condition, the performance level of the engine will drop dramatically. One will notice how the engine will hardly pick up speed as it should in normal conditions. The accelerator will act like it’s not working properly. Serous care should be taken if any of these symptoms occur or else damage will be caused to the essential part of the vehicle.
Sputtering
Sputtering in a vehicle is related to a clogged oil filter. 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. Users that experience such sound should ensure to fix it as soon as possible before more damage is done to the vehicle.
Dropping Pressure
One can read the oil pressure gauge from the vehicle’s dashboard to ensure the pressure is not dropping. Discovering a steep drop in oil pressure is a problem that must be examined. Naturally, engine oil pressure will not drop more than a fraction of a percent while driving. So, a drastic pressure change is a sign of error in the oil flow.
Dirty Exhaust
A clogged oil filter causes black or dirty exhaust to come out of your car. Users will often smell oil burning as it passes into the exhaust pipe. This is a sign of a bad filter that needs replacement as soon as possible before more damage is done.
