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Alan's Column

Spreading the word


Part II


Dual Oil Filtration

Part II

Blue thingee

Having introduced ourselves to you and initially described what we are about, it is time to elaborate on our subject of filters and filtration. An informative explanation is certainly needed especially where vehicle owners are concerned. Once one understands the reason and practicalities of the filter system, its capabilities, and its failings, then the whole story becomes clear, and you the end user will certainly view the situation in a different light.

First of all lets examine what happens to the oil. Contrary to belief, Oil in itself does not wear out. However it is subjected to the rigors of the planet which none of us can escape. IE Water moisture, Dust particles, Pollen, Hot and Cold atmospherics, added to which it has to contend with the products of combustion as well when applied to IC engines.

Engines being subjected to frequent and extreme temperature changes, aided by the presence of a water jacket surrounding the cylinders, generate condensation. When this occurs internally, the water moisture ends up being absorbed into the oil. This in turn starts a chemical reaction, which if not controlled, induces the oil to becoming acidic. The presence of acid in the oil then attacks metallic parts of the engine eating into components and vital parts such as bearing surfaces.

To combat the effects of this unwanted intrusion a chemical additive package is added to the oil to protect it from the rigors of atmospheric dust, water, and combustion product intrusion.

This is the product that determines the useful working life of the oil.

All the time the chemical additive package remains active and strong enough to protect the oil from the environment, the oil is able to work effectively at protecting your engine. Once the strength of the additive package is lost then the oil on its own is no longer able to protect your engine and its working parts effectively, therefore necessitating the established routine of periodic oil changes.

The next area of attack on the oil comes from the dust in the atmosphere. Just about everybody has witnessed how much dust is floating in the atmosphere of a room when looking into a shaft of sunlight streaming through a window. It is quite frightening, considering we are all breathing this mixture into our lungs. An engine also breathes air. This means as the air passes through the engine block, the oil too is absorbing dust. The amount of dust the oil carries round the lubrication system of the engine determines the abrasive wear rate mechanical parts are subjected to. If the AIR filter fitted to your cars engine was made so that it absorbed all dust particles entering the system, your engine would be starved of air and therefore would not run. After a period of time the oil in your engine is carrying so much dust pollution it is impossible for it to protect your engine in the way it was intended. Hence the reason for fitting the best effective filtration system that can be employed.

Now a few facts and figures to highlight the problem we are dealing with.

Water intrusion in any quantifiable form in any oil dependent fluid power system is extremely bad news for reasons described above.

Solid particle and dust intrusion: Particle content of a size of 3 microns and larger generates abrasive wear damage to moving parts. (The human eye is just capable of visually seeing solid particles of 12 microns in size in natural light with no magnification.) Your current oil filter at best can only stop and hold solid particle content of 20 microns in size and larger from circulating round the engines lubrication system. To be any more effective oil flow circulation would be compromised, resulting in oil starvation. However, to avoid wear we need to filter out solid particle content from the oil to a level below 3 microns. We operate at level of 1 micron.

When you replace your vehicles oil filter, you trust it is the right one for the car. If it is a genuine replacement part from your dealership then there is no question, it is designed for your vehicle. However: When buying alternative units from other suppliers, unless specified for your vehicle, it is worth remembering you could be using one of four types.

The four types are categorized as follows.

1st and cheapest unit is made up of just a plain filter element with no built in safeguards.

2nd contains a filter element with a non- return drain valve fitted specifically to stop the oil draining out of the canister.

3rd contains a filter element with a non -return drain valve and a pressure relief valve just in case the oil flow through the filter element becomes restricted. This valve opens up effectively bypassing the filter element allowing oil circulation to be maintained.

4th contains a filter element which is assembled with a non -return valve and a pressure relief valve, also added is a perforated support tube mounted through the centre of the element, this tube supports the filter element and stops it from collapsing. inwards. A condition that could occur under extreme pressure conditions or if the filter element becomes so clogged with sludge compounds that oil flow is severely restricted.

It is not easy to recognize which type is supplied for a particular vehicle, although one can see by looking at the mounting plate end, if the element is fitted with a non- return valve.
We always use types 3.and 4.for safety reasons.

Now we look at the second filter fitted to our unit. This element is designed to work on the bypass principle, so called because the oil passing through this filter is returned to the sump or oil reservoir without circulating through the engine system.

The density and design of the filter media which goes into making up this element is such that it cannot be used in the main oil flow stream, as it would restrict any such flow rate, starving the working parts from oil lubrication. We also ensure that the correct working pressure of the lubricating system is maintained and fully protected by deliberately limiting the oil flow rate through this filter element, control is by means of a metering jet. The actual volume of oil passing through this filter element is not critical so long as the flow rate is adequate enough to remove any unwanted contamination faster than it can accumulate in the oil, and of course, after passing through this element, the oil is able to be returned back into the engine sump.

The make up of this filter element also separates and retains any water intrusion that is absorbed by the oil, as the oil passes through this filter, the special fibre mix allows the oil to flow through the media but, any water passing through the media carried by the oil is trapped and retained by the fibres. The heat generated by the engine evaporates the water content held by the fibres, maintaining its separation from the oil dispersing it eventually through the breather system and out to atmosphere via the exhaust. There is quite a debate on how this cycle of events is achieved. Whatever the answer, the system is extremely effective at producing the desired effect. One major point that is not given much consideration is, that the build up of contamination whether it is either water or solid particle content is a slow process and an accumulative one, therefore the process takes time. In other words, if both water and solid particle content were fed to the oil by the shovel full, then of course nothing one did in the way of filtration protection would work. This point is often overlooked. By fitting the bypass element into the system any pollutant material present is removed before it has a chance to accumulate. This means the additive package that protects the oil is preserved and not activated. The oils visual condition after many thousands of miles will show no signs of sludge build up or emulsification. The oil will however change its appearance to a brown colour retaining a transparency and clean look, whereas, an oil not protected with a bypass filter system will eventually change to a black non transparent appearance. The reason the oil changes to a brown colour is because of oxidation. The condition is caused through heat generated by combustion and is quite a normal process, and is harmless. It is off putting though, and takes a little getting used too. Laboratory tests are available to confirm an oils condition, and such tests are quite useful for determining the general health of an engine.

Most people think of an engine as a power tool that can be used to travel from A to B. and it is something that more often than not is subjected to considerable abuse. One feature to emerge is quite noticeable. It is the enhanced smooth vibration free running of an engine when fitted with our system, Your engine is in fact a precision machine designed for a particular purpose and therefore should be treated with the same respect as a precision machine tool designed to manufacture a precision made product. If the vehicle owner trains his or her mind to this way of thinking and follows routine maintenance procedures the vehicle you drive will always transport you to your destination with utmost reliability. Your overall servicing costs will have been reduced to an absolute minimum, and time lost waiting for a breakdown recovery vehicle to rescue you from the hard shoulder on a motorway or else where will only be necessary in a real emergency.

I hope you have found this explanation interesting and informative.

Later on I will put together a page or two together with some statistics which will bring home to you just how uneconomic owning your own vehicle really is when considering the big picture, and what it means for the future of transport.

Alan Roper

4 May 2005

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