Oil Filtration System: The Ultimate FAQ Guide

This guide covers all information about oil filtration system.

From definition, components, working principle, specification, function to features, among other critical aspects.

So, if you want to an expert in oil filtration system, read this guide.

Table of contents hide

What is Oil Filter?

This is a mechanical component that will eliminate dirt, contaminants, and fuel that fails to burn from circulating.

It will enable fresh oil to circulate in the engine and prevent contaminants from doing so.

That is why it is important to replace or clean it after some time.

It is possible to find it on a vehicle’s hydraulic system like the power steering or automatic transmission.

Engines that use gas turbines, for instance, jets, will use an oil filter.

In summary, all automobiles use an oil filter for purifying oil by eliminating contaminants.

oil filter

Oil filter

What is an Oil Filtration System?

This is a unit that will perform the function of removing contaminants from the engine, hydraulic, lubricating, and transmission oil.

What are the Benefits of Having an Oil Filtration System?

Here are the benefits of using an oil filter system:

Prevention of Wear and Tear

These filters will prevent the moving components of the engine from wearing and tearing out.

This increases their durability.

Extend the Life Span of An Engine

Engines require clean oil to circulate to make them perform in the best way.

The best oil filtration systems will inhibit contaminants and dirt from reaching the internal parts of the engine.

The effect of this will boost the engine’s power and its life span.

Prevents the Heat in the Engine from Spiking

Low-quality oil will eventually make an engine overheat.

As contaminants build up in the oil, it will wear out the engine and prevent heat conductivity.

Oil filtration systems assist in keeping the components of the engine by ensuring their lubrication.

The pure oil-free of contaminants will prevent the engines from overheating.

It Protects the Engine Against Oil Oxidation

The oil in cars will oxidize no matter how suitable or unsuitable the road conditions you are driving.

Oxidation adds more contaminants to the oil thus lowering its efficiency.

The oil filtration system will prevent contaminants from getting inside the engine.

This helps in preventing the motor from damages.

What are the Types of Oil Filters?

Here are some major oil filters you will find:

Mechanical Oil Filters

These filters have bulk material or pleated paper filters.

It will trap the contaminants that suspend in oil.

Magnetic Oil Filters

This is also a type of secondary oil filter that provides additional support to full-flow oil filters.

It is suitable for eliminating metallic impurities from the oil.

However, they will not remove dust or grime.

Sedimentation Oil Filters

These filters allow contaminants that are heavy than oil to settle at the bottom of these filters with the assistance of gravity.

Centrifugal Oil Filters

This is a rotary sedimentation filter that applies centrifugal force and not gravity to eliminate contaminants from the oil.

It is hard for impurities to block this kind of filter than it is for conventional filters.

Besides, they also separate water from oil since oil is lighter than water.

High Efficiency [HE] Oil Filters

They are a kind of by-pass oil filter.

Also, they show to extend the intervals of oil drains.

Besides, their pore size is around 3 micrometers, which studies show to lower engine damage.

Some fleets increase the oil drain interval to around 5 to 10 times.

Full-flow Oil Filters

These are some of the most common oil filters.

They are also known as primary oil filters.

It functions by eliminating contaminants from the oil that the engine utilizes.

Also, they are suitable for colder temperatures.

This is because cold temperatures will make the oil thicken.

Besides, full-flow oil filters will enable oil to move freely in the engine than other types of filters.

If a filter is restrictive, the engine may fail to get oil hence causing it to wear and tear.

This filter will provide adequate oil to the engine to ensure it performs well.

Secondary Oil Filters

These are also known as by-pass oil filters.

Some automobiles need secondary oil filters to provide support with full-flow filters.

Also, the design of these filters makes them purify not more than 10% of the engine oil.

This makes secondary oil filters eliminate contaminants that a full-flow filter did not remove from oil.

Besides, they lengthen the life of motor oil.

They will also provide extra protection to the engine.

Cartridge Oil Filters

This is a type of full-flow filter which is easy to use and is not that complex.

One will mount this filter in an upright position.

This enables one to easily access and inspect it without the need to remove the oil in the system.

Cartridge oil filters are available as metal and fiber.

The most common type is fiber since it is easy to recycle.

Spin-on Oil Filters

This is also a type of full-flow oil filter.

It has steel canisters that have a paper element.

Besides, it is easy to install and fix as it is simple and needs fewer tools.

Spinner Oil Filters

This is a type of secondary oil filter which applies centrifugal force to remove impurities from engine oil.

Spinner oil filters have the capability of producing over 2000 newtons of force, which is more than gravity.

They have the advantage of eliminating the tiniest impurities from motor oil.

Thermal Chamber Oil Filters

First, they operate by filtering all contaminants from the oil.

Secondly, they heat oil thus increasing the temperature of the oil.

This means some particles will burn up by the increase in temperature.

Diff types of filters

Diff types of filters

What is the Difference Between By-pass System and Full-Flow System?

Here is how these two compare:


This system has pumps that send pressurized oil via a filter to the bearings of the engine.

Thereafter, the oil goes back to the sump through gravity.

For dry sump engines, a second pump evacuates oil that reaches the sump then proceeds to a remote tank.

This filter protects the engine from wear and tear which happens due to abrasion.

full flow system

Full flow system


This is a secondary system in which bleeds from the primary oil pump will supply oil to the bypass filter.

The oil then returns to the oil tank by not passing the engine.

This secondary system will maintain the condition of the oil by keeping off dirt, water, soot, etc.

This assists in keeping the full-flow system free from blockages.

bypass system filter

Bypass system filter

They were once common in commercial and industrial applications to lower maintenance costs.

Nowadays, they are common in private applications.

Also, this system must not alter the oil feed pressure in the full-flow system.

One can achieve this effect by ensuring it is independent of other systems.

What are Pressure Relief Valves?

This is a system that allows oil to bypass the filter when it encounters a restrictive flow.

Also, it will assist to supply the engine with oil.

A filter bypass happens when the filter clogs or oil thickens due to cold weather.

A pressure relief valve is a common component to include in oil filters.

The excess oil that drains from filters has an anti-drain-back valve that holds oil within the filter if the engine shuts down.

This happens to prevent a delay in the oil pressure from building up once you restart the system.

When you do not have an anti-drain-back, pressurized oil has to fill the filter then go towards the parts of the engine.

This situation can cause moving parts to wear and tear quickly due to the lack of oil.

Pressure vavle

Pressure valve

Why is it Important to Have Clean Motor Oil?

When you do not clean oil, it will saturate with particles and impurities that will cause wear and tear of the engine parts.

Dirty oil will damage the pump and the bearings as well.

Therefore, clean motor oil ensures the engine parts remain in good working condition.

Also, clean motor oil enhances the longevity of these parts and lowers maintenance costs thus saving you some money.

How Does an Oil Filtration System Work?

Here is how an oil filter works:

Entering the Filter

The pump of the engine oil makes it move into the filter via the perimeter holes at the base of the plate.

An anti-drain back system opens as oil starts to enter the oil filter under pressure.

This membrane shuts when the engine is not functioning thus closing all the holes of the filter.

It works by ensuring the oil remains in the filter hence preventing dry starts where an engine powers on with no oil.

Filtering Process

Dirty oil passes via the filter media under pressure.

This makes impurities stick on the filter and oil passes through via the central hole.

Exiting the Filter

The clean oil now exits the filter and into the engine.

What are the Parts of an Oil Filtration System?

These are the parts that make up an oil filter system:

Tapping Plate

This is the entry and exit part of the oil filter.

Also, it has several small holes around its edge that enable oil to flow freely into the oil filter.

A threaded hole at its center allows oil to flow out of the filter as it enters the engine.

Anti-drain Back System

This is a rubber valve with flaps.

It operates by preventing oil from entering back to the filter when the engine is shut down.

This component is important as the filter is usually between the middle and bottom parts of the engine.

Filter Medium

This part has several microscopic celluloses and synthetic fibers like glass and polyester.

It functions by enhancing the efficiency and durability of the filter.

Besides, it has resins in it to offer more stiffness and strength to the medium.

More synthetic fibers are available in high-performance oil filters.


This is the part of the filter that has several folds thus increase the surface area.

A large surface area ensures oil gets into contact with this part thus an effective filtration process.

The thickness of the medium will determine the number of available pleats.

Central Steel Tube

This part will provide sturdy support to the filter.

It also enables oil that has undergone filtration to exit the filter and enter the engine.

The amount, dimension, and position of the holes enhance the effectiveness of the flow of oil.

It also inhibits oil restriction.

Relief Valve

Thick oil can prevent the filter from filtering it, especially on a cold start.

This means you need to prevent the engine from oil starvation.

Relief valves will open when there is enough pressure force to make the spring move downwards.

This enables dirty oil to enter the filter via the top section.

It also ensures there is oil within the filter at all times.

End Discs

The function of this part is to prevent oil that has not undergone filtration from leaking back to the central steel tube.

The material that makes up this part can be fiber or metal.

Also, the end disc bonds to both ends of the filter medium.


This is a metal that functions as a leaf spring.

It is responsible for keeping the filter medium together with the end disc tight on the tapping plate.

What are the Symptoms of a Bad Oil Filtration System?

Here are some signs that will show an oil filtration system is bad and needs replacement:

A Poor Performance

One sign of an oil filtration system that needs replacement is that the car will not accelerate like it usually does.

It may feel that the acceleration pedal is not functional.

The engine will operate but not as efficiently and even light sputtering may lead to huge problems.

When you continue operating the machine under this circumstance, essential parts of the engine will break down.


Sputtering is a situation when the oil filtration system is not releasing oil efficiently.

This means the automotive will not maintain its speed.

The sputtering may start softly but worsen over time.

Always replace the filter when you notice such a problem to eliminate the sputtering.

Metallic Noises

The metallic parts will come into contact with one another since there is a clog in the oil filtration system.

This is evident when the machine is operational as you will start hearing metallic noises coming from the engine.

In such a situation, stop operating the machine immediately to prevent further damage to the engine.

It is advisable to replace the oil filtration system and apply more oil to the system immediately.

A Drop in Oil Pressure Gauge

In vehicles, you can see the oil gauge pressure displaying on the dashboard.

Pressure drop is a sign indicating an error in the flow of oil.

When you notice a pressure drop, take caution as it may lead to irreversible damages to the engine.

Dirty Exhaust

Exhaust fumes exiting the vehicle can be dirty or black when the oil filtration system has clogs.

Also, you may sense burning oil smells as it passes via the exhaust system.

It is advisable to replace the oil filtration system immediately.

Cleaning the filter can eliminate clogs and sludge that accumulate over time.

This will prevent extra damages to the engine and the environment too.

What Sources Will Contaminate Oil?

Here are some sources that will contaminate oil:

External Environmental Sources

Moisture may enter the system through external elements like water blasting at high pressures, washing, etc.

Air Vent

This part may cause particles, dirt, and water to enter the engine and contaminate the oil.

Internal Environment

There are instances where condensation in the engine can introduce water in the oil.


Water may form due to oxidation.

High temperatures and dirty oil lead to the formation of acids, water, and resins.

Rust and Corrosion

Water causes the formation of rust on metals.

This may enter the oil system and contaminate the oil.

Leaking Coolers

When the cooler is leaking, it will introduce water in the oil’s reservoir.

These contaminants will eventually lead to:

  • Corrosion of the metals in the system.
  • A reduction in the lubrication system thus leading to wear and tear.
  • It may cause a diminish in the dispersion rate of oil.
  • Components in the engine may isolate or stick.

What Types of Filtration systems Exist in the Market?

There are two types of oil filtration systems:

Primary Oil Filtration System

This is the first filtration step that involves screening and eliminating most of the impurities in the oil.

They perform a bulk of the oil filtration process and may let few sediments pass through.

These sediments may prevent the freezing of oil in cold temperatures or from thickening.

The manufacturer usually installs these filters.

Secondary Oil Filtration System

This stage involves cleaning the oil of all remaining contaminants from the primary oil filtration system.

They work with the primary oil filtration system.

Besides, they only filter up to 10% of the oil.

Also, they work independently of the primary oil filtration systems.

What is Beta Rating?

It is the ratio of the number of particles before filtration to those after filtration.

A higher beta ratio means the oil filter has a high capture efficiency.

This means it is a piece of vital information when one is selecting an oil filtration system.

They highlight how efficient the filter is with contaminants of various sizes.

It originates from a Multipacks Method for Evaluating Filtration Performance on Fin Filter Element [ISO 16889:1999].

Beta ratio

Beta ratio

What is the Function of Oil in an Engine?

Engine oil has several functions and they include:


This is the main function of engine oil.

It functions by lubricating the moving parts of the engine which are always in friction.

Therefore, it lowers friction thus enhancing the lifespan of the engine by preventing tear and wear of engine parts.


Energy is lost by combustion and the friction between the mechanical components.

This allows the temperature of the engine to increase.

The lubrication aspect of the engine oil helps to relieve heat through the lubrication circuit.

It enhances the coolant, which only cools some areas of the engine.


Although less well known, the cleaning capacity of the engine oil is important.

Microscopic deposits are built into the engine and live in suspension.

They can comprise debris or residues of combustion.

Not using engine oil means the engine will clog and its output will decrease.

The engine oil flow constantly takes these contaminants to the oil filter, where they filter out.

Prevention against Corrosion

Oil combustion releases corrosive acid that can destroy the metallic components of the engine.

Through the addition of additives to new engine oils, corrosion slows down.

However, with time and in the presence of oxygen, the engine oil will oxidize and no longer prevent corrosion.

That is why one has to replace engine oil regularly.


Engine oil also improves the sealing of the engine and, more precisely, the sealing of pistons and cylinders.

A protective film deposits between the different components, and seal clearances that may occur.

Gap Filler

The space between the piston and cylinder is not that smooth.

Engine oil will assist in improving efficiency and performance as a gap filler in these parts.

Fuctions of engine oil

Functions of engine oil

How Does Inline and of Line Fundamentals Compare?

Inline uses pressure or system flow like suction filters, pressure filters, and bypass filters.

Off-line means it works from the tank via the filter and back again to the tank by a separate pump in constant flow.

What are Some Features of a Good Oil Filtration System?

They include:


This illustrates the ability of the filter to hold contaminants with no need for replacement.

The type of media and the configuration of the filter influences its capacity.

A better capacity means better mileage.

As the filter reaches its capacity, it releases unfiltered oil into the engine through the dump valve.

Housing Design

Lack of standards in the automotive industry means every manufacturer and model has its specifics.

The weight and design of the housing determine if you can install it in your car.

Ensure the specifications of the filter are in line with your vehicle’s requirements.

Type of Filtration Media

All oil filters have a material that filters oil.

This material can be synthetic, cellulose, or both.

Synthetic comes from polyester, nylon, or glass, and offers the highest filtration rate as it has tight fibers.

This means it can eliminate even the tiniest contaminants.

Cellulose is cheap than synthetic media and has low quality.

Blending these media offers the best deal in terms of cost and efficiency.

Ease of Use

Oil filtration systems are of varying shapes and sizes.

Ensure the one you choose fits your engine.

What are Some Trends that Influence an Oil Filtration Technology?

Internal combustion engines offer better consumption and emission requirements.

This is one of the trends coming up in addition to others still in development.

What is it Reasonable to Buy an Oil Filtration System?

A good system allows your engine to operate optimally and be durable.

It also prevents damages due to wear and tear.

How Often do You Need to Replace Your Oil Filtration System?

It is suitable to chance oil filtration systems every time you conduct an oil change.

This translates to 10,000 km for petrol engines and 15,000 km for diesel engines.



Other considerations are when the service engine light is on and you drive in extreme conditions.

Does Synthetic Oil Require a Special Oil Filtration System?

It is important to confirm with your vehicle’s manufacturer lest you void your warranty.

Also, oil filters for modern vehicles can clean out any type of oil.

Major manufacturers of motor oil do not recommend special oil filtration systems for synthetic oil.

This is because better oil filtration systems are good at removing contaminants.

What Happens When You Fail to Change Your Oil Filtration System?

These include:

  • A loss in the engine oil pressure.
  • Internal damage to the engine.
  • No lubrication to engine components.
  • Faster wear and tear of engine parts.
  • Pollution of the environment.

Is There a Difference Between Synthetic and Conventional Oil?

Synthetic oil is better than conventional oil.

Also, it offers high performance and protection than conventional oil.

Conventional oil uses less-refined base oils than synthetic oil.

This means conventional oil has less chemical stability, oxidizes easily, and loses the protective qualities quickly.

Is it Possible to Use an Oil Filtration System Twice?

It is advisable to use a new oil filter once it’s full as it is cheaper than a new engine.

Should Your Pre-fill an Oil Filtration System Before Installing?

Pre-filling the filter with oil ensures the engine does not start dry.

This provides the engine with enough lubrication as it builds up the oil pressure.

What are the Benefits of a Synthetic Oil Filtration System?

Synthetic oil filtration systems offer:

  • High engine efficiency
  • Better capacity
  • Durability.

When is a Premium, High-Capture Efficiency Oil Filtration System a Good Choice?

There are several high-performance oil filtration systems in the market.

Instances to use this filtration system are:

  • When you are driving luxury car engines
  • High-performance driving like motorsports.
  • When you are dealing with high-performance engines.
  • In extreme cold starts.
  • For long engine life.
  • They are suitable for low viscosity oil.
  • When conducting towing services.

As you can see, there are many factors to consider when choosing oil filtration systems.

That’s why at FilSon, we offer perfect solution for all your oil filtration systems.

Contact us today for all your oil filtration system’s needs.

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