DPF cleaners.

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Billy Bananahead
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Re: DPF cleaners.

Post by Billy Bananahead »

It doesn't help if you drive with cheap and nasty supermarket diesel in the tank.
I always use the "super" with more detergents which helps the DPF stay cleaner.
johnnyboxer
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Re: DPF cleaners.

Post by johnnyboxer »

Richard Simpson Mark II wrote:As said...modern diesel cars are not suitable for pottering about on short journeys.

I don't know if any of the pour-in products work. You can buy electronic tools that enable you to force a 'hot' regen if the car won't do it on its own.

A very important, and often misunderstood point is that using the wrong engine oil will quickly clog the DPF with metallic ash that cannot be removed with thermally. Modern oil has a lot more than oil in it, and one of the things it contains is zinc dialkyldithiophosphate (aka ZDDP). This is designed to decompose at higher engine temperatures and its components form an anti-wear coating on components such as cams. The coating is wiped off by rockers etc, and then reforms.

And there's the problem. All engines have residual oil on the bore, left by the descending piston, which gets burned in the combustion stroke. The metallic elements in ZDDP are caught in the exhaust stream then accumulate as ash on the ceramic filter. Eventually they partially fill the filter, leaving little room for soot and causing a massive increase in backpressure! Unlike soot, they don't burn.

Engine manufacturers now specify what are called Low or Mid SAPS (sulphated ash, phosphate and sulphur) oils, which contain less ZDDP and more of other non-metallic anti-wear additives for DPF-equipped engines. If these oils are used, the ash doesn't build up so fast, but many garages and car owners don't understand this and use the 'wrong' oil.

If you are interested (someone must be) there's an article in the December 2020 Transport Engineer that you can download here

http://www.transportengineer.org.uk/tra ... -magazine/

Can't think who wrote it...
Indeed
The village garage who services my Hilux with dpf and used low ash oil
Seems to do the trick
Other thing with a lot of engines, if you only do a partial regen, but be unburnt diesel ends up in the sump and the oil level rises and dilutes the oil and leads to premature engine wear Image
2 years ago we went back to a petrol car after 20 years of diesel cars
We only use Diesel engines in our commercials now as they get worked
We buy things we don't need



With money we don't have



To impress people we don't even like
Richard Simpson Mark II
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Re: DPF cleaners.

Post by Richard Simpson Mark II »

And if the oil/fuel mix in the sump gets high enough the pistons splash it in to the combustion-chamber and you get a diesel runaway.

Great fun to watch, if you are not too close, and it's not your vehicle.

https://video.search.yahoo.com/search/v ... ction=view
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bowber
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Re: DPF cleaners.

Post by bowber »

Thedktor wrote: Sat Dec 05, 2020 6:39 am My lad's 2.0 tdi Astra would occasionally do a regen, basically it pumps extra fuel into the exhaust to burn off the soot. You know its doing it cos it smells and the fan runs.

He bought some Halfords stuff which everyone "on the internet" swears works - it is designed to lower the combustion point of the soot. I was very sceptical but it does appear to work!

He did take it for a blast up the motorway in 4th which undoubtedly helped but has been fine since.

I think later engines say 2014/15 on burn much cleaner so don't clog up the DPF so easily, pre that engine technology was not quite good enough and the DPF was kind of a cover-up of sooty engines. Just my theory :)
My in laws bought a new Vecrta estate, they eventually gave it to their son who used it for a while until suddenly it started filling the sump with diesel, after it was in and out of the garage a few times at vast expense he sold it for a couple of hundred quid just to get rid of it, new injectors, various static regens etc. Perfectly good car ruined by a poorly designed "environmental" system.

Steve
Richard Simpson Mark II
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Re: DPF cleaners.

Post by Richard Simpson Mark II »

Also a Daihatsu problem...it's what killed many a Fourtrack.

The excess fuel washes the bores, which wears the rings, which increases the seepage of fuel into the sump, which originates on the Daihatsu from poor injector sealing.
Sanqhar
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Re: DPF cleaners.

Post by Sanqhar »

johnnyboxer wrote

"2 years ago we went back to a petrol car after 20 years of diesel cars"

The same for me.

Diesel particulate filters are flawed technology.

My post "fix" Yeti only seemed to have "active" regenerations whereas before the fix they all seemed to be "passive". I had a free replacement EGR and once the trust building measure guarantee ran out, I bailed out.

Pleased with my 1.5 Sel dsg

tom
... and today was a good day in the life of...
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Hugh
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Re: DPF cleaners.

Post by Hugh »

Greetings,

Richard, when I was an apprentice I spent some time in the 'commercial' section and remember a truck doing exactly that. The mechanic I was working with told me to get down in to the pit as the engine of a Bedford TK screamed for about two minutes before self destructing with parts flying up through the workshop roof and every direction in between. Very scary :shock:

TTFN

Hugh.
Richard Simpson Mark II
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Re: DPF cleaners.

Post by Richard Simpson Mark II »

If an engine is 'making oil'...ie the level is going up, not down, the dipstick, then this is an early warning.

Yes, when they grenade, it is a sight never forgotten.
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