Redex Diesel System Cleaner

AdrianC

David713 said:

fred246 said:

White spirit is good for cleaning things.

So is hot soapy water but I wouldn't put that in my fuel tank.

I have to admit, I'm astonished that Fred - of all people - should fall for the snake-oil-profit-centre-upsell.

David713

AdrianC said:

David713 said:

fred246 said:

White spirit is good for cleaning things.

So is hot soapy water but I wouldn't put that in my fuel tank.

I have to admit, I'm astonished that Fred - of all people - should fall for the snake-oil-profit-centre-upsell.

He probably saw a YouTube video extolling the virtues of the stuff.

Goudy

Most diesel additives will contain various amounts of 2-Ethyl-Hexyl Nitrate (2-EHN) along with some other chemicals that are mainly there as lubricants.

2-EHN is a cetane improver and the higher the cetane rating of diesel, the better the fuel burns as it has a lower autoignition point, which is the point it self ignites when compressed. As diesels are compression igntion engines this lower autoignition point leads to a quicker, more complete combustion.

So it does tend to improve mpg and reduce emissions, it's not totally snake oil.

It also reduces diesel knock a little so owners do tend to notice an "improvement" when using it.

Now why would you use it, as already suggested you can buy higher cetane "Super" diesel from the pump, but that does have a slight drawback.

Most modern, higher cetane "Super" diesels use a synthetic gas to liquid component and this actually reduces the fuels density and so the energy the engine can get out of it. This is offset a little against the improved combustion, mpg etc though.

To use a bit of higher 2-EHN content additive in regular diesel every now and then is probably a little more cost effective than using "Super" diesel 100% of the time. It will nudge the emissions down a little and should improve mpg over the less dense "Super" diesel as you are now burning a higher cetane, denser fuel, though you probably wouldn't notice it in the pocket unless you did millions of miles.

As for MOT, all things being equal, running either through the tank a week or so before should help the emissions, but neither are going to mask a fault that creates a serious emission problem.

AdrianC

Goudy said:

2-EHN is a cetane improver and the higher the cetane rating of diesel, the better the fuel burns as it has a lower autoignition point, which is the point it self ignites when compressed.

So it fires earlier.

Not a problem in modern diesels which automatically adjust pump and injection timing. Last thing you want in an older one, though.

fred246

I have tried a couple of bottles of Millers Diesel Power Ecomax in the 16 years and 170000 miles I have done in my diesel. You try and convince yourself that it might be better. I obviously wasn't impressed enough to keep using it.

justworriedabit

Morning OP

Mr J used it on his car many blue moons ago when we had older cars, useless.

They rarely are worth it - decide for yourself if you may benefit - link from a well known motor mag

https://www.autoexpress.co.uk/car-news/33200/fuel-additives-are-waste-money

BOWFER

AdrianC said:

BOWFER said:

I'm sceptical about additives, but one I did read very good reviews for is ARCHOIL AR6400 D-MAX pro diesel DPF cleaner.
It's not cheap, it's +£20 for 400ML.
I've got a bottle in the garage for if/when the wife's Evoque DPF displays a light.

https://www.thedieselgarage.com/attachments/sds-20ar6400-20nl-en-pdf.36025/

40-45% kerosene
30-50% a curing agent for epoxy adhesives
20-25% a petrol product

And for that, they charge £50/litre.

If it works, i don't give a damn.

AdrianC

BOWFER said:

AdrianC said:

BOWFER said:

I'm sceptical about additives, but one I did read very good reviews for is ARCHOIL AR6400 D-MAX pro diesel DPF cleaner.
It's not cheap, it's +£20 for 400ML.
I've got a bottle in the garage for if/when the wife's Evoque DPF displays a light.

https://www.thedieselgarage.com/attachments/sds-20ar6400-20nl-en-pdf.36025/

40-45% kerosene
30-50% a curing agent for epoxy adhesives
20-25% a petrol product

And for that, they charge £50/litre.

If it works, i don't give a damn.

"If" is a very big word for only two letters.

"Placebo effect" is a lot longer.

Goudy

AdrianC said:

Goudy said:

2-EHN is a cetane improver and the higher the cetane rating of diesel, the better the fuel burns as it has a lower autoignition point, which is the point it self ignites when compressed.

So it fires earlier.

Not a problem in modern diesels which automatically adjust pump and injection timing. Last thing you want in an older one, though.

Yes, though more like self explodes sooner under compression.

It's still useful to an older pump timed diesel engines though a modern common rail with multiple and adjustable injection band widths and knock sensors should make more of the fuel.

Very much the same as a modern petrol engine can accomodate higher octane petrol (that resist autoigniting under pressure better than low octane petrol), some engines do it better than others.

It's not so much the timing of injection, though that's obviously important to make the engine run, it's the speed of what's injected igniting under compression. A quicker more complete "bang" is the goal.

Low cetane takes longer and slightly more compression (lost effort) to ignite, so the "bang" takes a tiny bit longer.

Multiple this by 4, 6 or 8 cylinders rotating at 2000, 3000, 4000 rpm and it all adds up.

There are a few other things that have a similar effect as 2-EHN though I wouldn't recommend them in a modern CR diesel engine!

2-EHN is already added to diesel in various amounts, so adding more in small doses isn't going to cause problems.

AdrianC

Goudy said:

AdrianC said:

Goudy said:

2-EHN is a cetane improver and the higher the cetane rating of diesel, the better the fuel burns as it has a lower autoignition point, which is the point it self ignites when compressed.

So it fires earlier.

Not a problem in modern diesels which automatically adjust pump and injection timing. Last thing you want in an older one, though.

Yes, though more like self explodes sooner under compression.

It's still useful to an older pump timed diesel engines though a modern common rail with multiple and adjustable injection band widths and knock sensors should make more of the fuel.

Very much the same as a modern petrol engine can accomodate higher octane petrol (that resist autoigniting under pressure better than low octane petrol), some engines do it better than others.

No, not really - because the ignition point is the same in the petrol. It's the spark timing.

It's not so much the timing of injection, though that's obviously important to make the engine run, it's the speed of what's injected igniting under compression. A quicker more complete "bang" is the goal.

Low cetane takes longer and slightly more compression (lost effort) to ignite, so the "bang" takes a tiny bit longer.

Multiple this by 4, 6 or 8 cylinders rotating at 2000, 3000, 4000 rpm and it all adds up.

Exactly.

Inject the fuel at the same time, and ignition is more advanced.
For the ignition to happen at the same time, you would need to retard the pump timing.