Questions about the 451 cdi Engine

[Phoph]

I have a few questions about the 451 cdi engine, that I hope somebody can answer (Fudge or Evilution are two names that spring to mind).

Is the 451 cdi engine different from the 450 cdi engine? If so, what's different about it?

Does the 451 cdi use a diesel particulate filter(DPF)?

How do I change the fuel filter on the cdi? (I have checked Evilution's excellent site, but don't know if I'm looking at the right information.)

I'm asking as I'm interested in using bio-diesel. I'm currently reading a book, and the author appears to be running a 450 cdi on home-brewed biodiesel, but information found here and here suggests that if the engine uses a DPF then the use of biodeisel is maybe not such a good idea.

Both those references (different areas of the same site) are well worth a read if you're interested in engines, biodiesel, or both.

New compatibility issues are arising with the use of biodiesel in engines equipped with actively regenerated diesel particulate filters, a new type of emissions system used in most diesel vehicles since the year 2007. Biodiesel incompatibility has been seen with blends as low as B5.

-and-

The issue of incompatibility arises not from the DPF, but rather from the injection process used to create an exothermic reaction which thereby burns off the soot from the combustion cycle. The resulting ash is then caught in the DPF.

TIA

Phoph

[J500ANT]

Re: Questions about the 451 cdi Engine

I believe the UK cdi does not use a particliate filter.

[10:45PM]

Re: Questions about the 451 cdi Engine

Is the 451 cdi engine different from the 450 cdi engine? If so, what's different about it?

Does the 451 cdi use a diesel particulate filter(DPF)?

the latest reincarnation of the diesel now has a closed particulate filter system, confirmation if you need it is in the sales blurb/smart site somewhere.
Earlier ones didn't , but I can't tell you when it changed just right now. You'll prob be able to find some info on it through google news archives.
here you go for starters: http://www.greencarsite.co.uk/GREENN...brid-drive.htm

http://www.electric-smart-car.co.uk/smart-cars-mhd.htm

They made these running improvements to improve it over the years.

[J500ANT]

Re: Questions about the 451 cdi Engine

I stand by my previous comment that the UK spec cars dont have a particliate filter. If you look in the handbook there is no mention, and if you go on thesmart.co.uk there is no mention of a particliate filter Exhaust gas purification/exhaust gas standard Oxidising catalytic converter/EU4. But if you go onto the German smart.com there is Flue gas / exhaust gas standard Oxidation catalyst with diesel particulate filter (closed system) [5] / EU4

I believe it depends on what the local "importer" has chosen.

[Phoph]

Re: Questions about the 451 cdi Engine

Thanks.

And now I add an additional question - what is a closed particulate filter?

A google search just comes up with results for DPF... I really have to learn about engines. I really do. I'm a man, for goodness' sake, and we're supposed to know all about engines!

[10:45PM]

Re: Questions about the 451 cdi Engine

A closed system uses the engine management to help regeneration from time to time, an open system relies doesn't.

I'm going to do some digging to find out about whether the UK car has it or not, closed or open.

[Fudge]

Re: Questions about the 451 cdi Engine

Thanks.

And now I add an additional question - what is a closed particulate filter?

A google search just comes up with results for DPF... I really have to learn about engines. I really do. I'm a man, for goodness' sake, and we're supposed to know all about engines!

A 'Cat'!

The excerpts that you have quoted relate in their language to VAG group diesel engines using 'Pump Deuse' (sp) and PSA HDI engines namely their 'FAP' range.

I have experiance of the VW regenerative DPF and it's shite, what happens is that when the exhaust gasses are cold (not at the ideal temp) there is more soot, the soot collects on the DFP and clogs it, in a PD engined VW you gat a light on the dash that informs you that your DPF is regenerating, then it all goes tit up and you get another, in the Caddy and Crafter you then HAVE to drive at circa 4000 rpm for about 15 minutes..... (15 - 20 miles in 6th at 80mph..... sound good?) hopefully you'll assist it's NON self regeneration..... if you're unlucky or a multidrop driver you'll then get a RED light and go into SAFE mode, you have no option but to have the DPF removed and replaced or sent for reconditioning.... their quite cheap on a crafter, only about £2500 a go..... and because your driving through town doing multidrop deliveries caused it you are unable to claim under warranty for it unless it can be proven there was a fault with the van, like it was over fueling.....

A mate that runs an Interlink franchise leased two crafters and is currently on his 3rd DPF..... he has great brand loyalty now..... NOT!

B5 is a waste of time, but I am sure all manufacturers have to support B5 mix on all EU5 engines..... 99% sure... I know VW, Ford (not the 2.5 or 3l engine) PSA and Merc

Hope that helps....

[J500ANT]

Re: Questions about the 451 cdi Engine

Andrew has had 2 cars with DPF - neither gave any issue, but then he does like to see the needle at the redline on occasion.

[Phoph]

Re: Questions about the 451 cdi Engine

Fudge, I read your post and all I understood was "Interlink franchise".mg:

I have learned what a regenerative filter does, though, so I'm a little more knowledgeable than this time yesterday. But I'm also more confused about the smart cdi. I looked in the owner handbook, and there is no indication as to whether there is a filter, just that there are three options:

• No DPF
• Flow-through DPF
• Wall-flow DPF

I suppose they could be alternative names for Regenerative and Open filters.

I think smart Croydon will be having a phone call from me later today...

[Phoph]

Re: Questions about the 451 cdi Engine

This suggests there is no DPF. Which is good news as it means using biodiesel is an increasing possibility... Once the warranty has expired, of course.

[that_chap]

Re: Questions about the 451 cdi Engine

Hi - n00b here considering a Smart Diesel and surprised by the existence of a biodiesel issue. (For clarity - I'm interested firstly in proper DIN-spec biodiesel, not homebrew, and not straight veg oil "svo".)

If one knew what the problem actually was, then one could consider whether any work-arounds or even extra checks could trivialise the problem.
Knowing what Smart's worry was would at least permit some informed risk assessment.

Those US links suggest that a common design practice for US (truck?) diesel catalysts could result in increased 'fuel dilution' of the engine oil, when running bio.
Diluting the engine lube oil is of course double-plus-ungood.
But 'fuel dilution' happens anyway, and oil change frequency is engineered to prevent major problems.

First dumb question: :newbie: does the UK 2009 rhd 451 cdi actually have such a Cat? The giveaway would be an excessively expensive exhaust system component ...
And then does it dump in extra unburned fuel (on the exhaust stroke) to 'fire up' the Cat? ?? :dollarey:

Such a Cat would be for dealing with particulates.
However, one reason for choosing to use Bio is that the particulates emissions are massively less when running bio! (Hence some folks running bio specifically to get through an MoT test.)
I turned up this reference to the 2007 (so non-UK) cdi having BOTH an "open" Cat AND even so, a bit of a problem with high particulate emissions. http://www.dieselnet.com/news/2007/06daimler.php Which sadly does not sound very 'green'.
Interestingly, there is NO mention there of after-combustion injection to 'fire' the catalyst - which is what the US articles say leads to fuel dilution -- rather it mentions 2-stage injection before combustion (to control diesel noise!)
And there is mention of a different (wall-flow) filter being considered "for 2008". Hmmm.

So what have we got in the UK in 2009?


If the problem isn't fuel dilution of the engine lube oil, what is Smart's objection to pukka DIN-spec bio?
Do they have the same objection in mainland Europe?
Does anyone have any 'factory' contacts to ask?

Proper bio, as well as reducing particulates, should actually be better for injector wear than fossil diesel. And with pump diesel throughout the EU being up to 5% bio without any signs or warnings, no modern diesel can have ANY bio-reactive fuel system parts (like natural rubber).

So what's the problem?

[that_chap]

Re: Questions about the 451 cdi Engine

As a 'PS' to that lot, I came across this

http://media.daimler.com/Projects/c2c/channel/documents/1546307_PI_smart_e.rtf

RTF (wordpad/textedit) document which claims that the cdi meets the Euro IV spec even without an 'open particulate filter' - but that one is fitted 'as standard' to reduce particulates by a further 40%.


And then it has this rather strange bit about an alternative second generation biofuel from Mercedes-Benz

As an alternative, the smart fortwo cdi can also be powered by innovative SunDiesel® synthetic fuel, without the need for modifications to the engine.
Mercedes-Benz introduced this second generation of bio-fuels as early as 2003. In contrast to conventional bio-diesel, which is manufactured using oil crops, SunDiesel® is created from a variety of organic materials – including wood and plant waste and other agricultural waste material. Therefore, this fuel does not present a threat to food crops. The advantages for the environment are numerous. SunDiesel® is almost completely CO2 neutral – the carbon dioxide produced by the engine during combustion is no greater than that absorbed from the air by the plants while growing. The alternative fuel is free of sulfur and aromatics and reduces the emission of carbon monoxide and hydrocarbons by up to 90 percent.

Hmmm.
Is it perhaps merely a case of "only use products supplied by M-B" ???

[that_chap]

Re: Questions about the 451 cdi Engine

Sorry, but there's a 'PPS'

M-B Press Release (July 2008) http://www.emercedesbenz.com/Jul08/1...rid_Drive.html

smart is also improving the environmental footprint of the diesel model in model year 2009 {ie October 2008 onwards} with a new closed diesel particulate filter instead of the open version that was previously used. The new system reduces the particulate mass in the exhaust gas to a minimum and, thanks to intelligent engine control, it is virtually maintenance-free with a long filter service life. With combined consumption of 3.4 litres per 100 kilometres (NEDC), the smart fortwo cdi with a 33kW/45 bhp engine continues to be the world's production car with the lowest consumption and, with emissions of 88g/km, it is still the CO2 champion. In future it will also hold a top position in terms of particulate emissions.

So it looks like a 'closed' filter from late 2008 onwards ... and for the UK too presumably?

[Phoph]

Re: Questions about the 451 cdi Engine

That it can be used with SunDiesel is interesting. I'm sure it's really no different from 'normal' biodiesel (which I saw being made today - very high quality, and very impressive). I find that, at least, very encouraging, together with the fact that there is no mention that Sundiesel can't be used with the closed particulate filter.

But what exactly are Open and Closed systems? I called smart Croydon today but didn't get to speak with anyone who could answer.

[that_chap]

Re: Questions about the 451 cdi Engine

...
But what exactly are Open and Closed systems? I called smart Croydon today but didn't get to speak with anyone who could answer.

Well I found this

The catalytically-coated ceramic monolith
contains long narrow channels open at one
end and blocked at the other. The exhaust gas
is forced to escape by passing through the
filter walls, trapping particulate matter (soot)
in the filter. At a high exhaust gas temperature,
the soot particles burn away and transform
into harmless carbon dioxide. The filter also
destroys carbon monoxide (CO) and diesel
hydrocarbons (HC).

in a PDF brochure for a 'wall flow filter', linked from this page http://www.dcl-inc.com/index.php?opt...d=15&Itemid=27


I presume that an 'open' one has tubes that go right through... Maybe that means an open one has to run hotter to be effective, because the particle's residence time is so short?

Incidentally, the 'wall-flow' product made no mention of needing to post-inject fuel to get the catalyst hot enough. (Which I think unlikely in a high fuel-efficiency engine anyway.)
No post-combustion injection, so no potential for the post-injected fuel to dilute the lube oil.


Sorry, but I cannot see the catalyst (or fuel dilution of the lube oil) being valid concerns.
However, I can understand concern about 'homebrew' bio (and boutique production!) Its reasonable to say 'if it ain't certified, it voids your warranty'.
But to say "no bio unless its M-B bio" does rather sound as though it might be marketing, rather than engineering, inspired.