What does EOLYS actually do?

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What does EOLYS actually do?

Post by Harlequin »

As title - what does it actually DO in a HDi engine?
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Re: What does EOLYS actually do?

Post by MikeT »

It "lowers" the combustion temperature of soot particles. IOW, the particles would not combust so well without it.
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Re: What does EOLYS actually do?

Post by Stickyfinger »

MikeT wrote: 20 Jun 2017, 16:58 It "lowers" the combustion temperature of soot particles. IOW, the particles would not combust so well without it.


Does it ?.....I thought it attaches itself chemically to those particles and as the Eolys itself oxidises it acts as a "starter" agent for the soot particles............I may be wrong.
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Re: What does EOLYS actually do?

Post by Paul-R »

It acts as an agent to reduce the temperature at which the trapped soot particles oxidise. I suppose it's correct in a way to say that the trapped particles wouldn't combust so well without it and they would then clog up the filter quicker.

On other marques that don't use EOLYS the combustion in the filter runs at a much higher temperature when the trapped soot is burned off.
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Re: What does EOLYS actually do?

Post by MikeT »

Stickyfinger wrote: 20 Jun 2017, 17:11
MikeT wrote: 20 Jun 2017, 16:58 It "lowers" the combustion temperature of soot particles. IOW, the particles would not combust so well without it.


Does it ?.....I thought it attaches itself chemically to those particles and as the Eolys itself oxidises it acts as a "starter" agent for the soot particles............I may be wrong.


Not sure what you mean here Alasdair "the Eolys itself oxidises it acts as a "starter" agent"? AFAIk, the additive doesn't combust (oxidise as you call it), hence why the DPF has to eventually be replaced or professionally cleaned with other nasty chemicals.
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Re: What does EOLYS actually do?

Post by Stickyfinger »

A catalyst to start the combustion of the particulates....................
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Re: What does EOLYS actually do?

Post by MikeT »

Stickyfinger wrote: 20 Jun 2017, 21:04 A catalyst to start the combustion of the particulates....................


Yes, it's a catalyst. I think we're agreeing aren't we? :-D
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Re: What does EOLYS actually do?

Post by Paul-R »

I think we're all agreed on that.
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Re: What does EOLYS actually do?

Post by Harlequin »

So - if the EOLYS is in the tank (via the pump or squirted in) then it actually helps the burning process?
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Re: What does EOLYS actually do?

Post by MikeT »

Paul-R wrote: 20 Jun 2017, 21:56 I think we're all agreed on that.


I'm all for being educated and I guess the context of the OP question maybe needs refining as well but for the purpose of eolys additives role in diesel emissions. my poorly constructed laymans response suits me just fine. :)
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Re: What does EOLYS actually do?

Post by Paul-R »

No implied criticism from me and I hope that you haven't taken it as that.
Harlequin wrote: 20 Jun 2017, 22:05 So - if the EOLYS is in the tank (via the pump or squirted in) then it actually helps the burning process?
Yes, exactly. The purpose of any catalyst is to help a chemical reaction (which is what burning is) take place at a lower temperature. Normally this is so that less energy is used to make a desired product. In this case it's the reduction in temperature that's important.
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Re: What does EOLYS actually do?

Post by Harlequin »

So EOYLS helps things burn . So what is the role of the DPF with it?

*leading question - I don't think my eoyls is being squirted into the fuel tank , ergo, if I drain some off and I manually put in 30ml a tank full)
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Re: What does EOLYS actually do?

Post by Paul-R »

The DPF firstly holds the small particles in place and stops them exiting into the atmosphere. Then, when the filter is sufficiently clogged, the burning process is initiated and the filter holds the particles in place until they're burnt away.

Once the particles have been oxidised there's an extremely small residue of cerine and non-combustible matter left in the filter which will eventually mean the filter needs a very deep clean or even replacement.
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