Mercedes new diesel engine.

[grober]

Mercedes have recently announced their new alloy block 4 cylinder diesel engine- the OM654 which will replace the OM651

Green Car Congress: Mercedes-Benz introducing new diesel family in E 220 d this spring; new OM 654 with 13% lower fuel consumption; diesel ?indispensable?

SOME MORE PICS HERE

http://eurocarfans.jp/?p=34850

 

[tangey]

Following the link shows that although peak torque is the same as the engine it replaces @ 400nm, the new engine it is only at peak for a range of 800 revs, as opposed to 1400 revs. New engine is peak 1600-2400 rpm, old engine peak 1400-2800 rpm.

That seems like a significant step back on that rather important metric.

 

[Deleted member 113659]

MB do seem to let themselves down in the deisel department. They are well behind Audi & BMW in regards to engine choices. (IMO)

Strange that this criticism is so publicised and yet they fail to be listening.

Mind you, what do I know???

Ant.

 

[grober]

A few remarks on the new engine.
1. Its smaller in capacity 1950cc V 2143cc a 9 % reduction

2. It retains the aft engine timing gear altho the lanchester shafts position changes.

3. A significant one -all the elements of the exhaust aftertreatment system are now configured directly on the engine itself and no longer on the vehicle.

4. It has a 13% reduction in fuel consumption and CO2 output

5. EMISSIONS-The new diesel engine is designed to meet future emissions legislation (RDE – Real Driving Emissions). In contrast to the current NEDC measurement cycle, the WLTP (Worldwide harmonized Light vehicles Test Procedure) cycle is aimed at ensuring that the figures for standard and real-world consumption are close together in future.
With support from insulation and improved catalyst coatings, there is no need for engine temperature management during cold starting or at low load. In addition to the advantages in terms of emissions, this results in fuel savings, especially on short journeys.

5 in particular may go some way to explain why the power/torque characteristics may have changed. Pointless having more power if emission regulations stop the vehicle from being used. Mercedes have already fallen foul of this in the recent cold running tests. http://www.mbclub.co.uk/forums/mercedes-news/205237-mb-emissions-law-suit.html Couple that to the future introduction of RDE that might explain it.

 

[Bellow]

The graph shows a 1500 rm torque plateau - am I missing something?

Anyway, a peak is just that. It has no span.

 

[grober]

Here's the old OM651 power /torque curves for comparison - think this is the twin turbo version.

from Mercedes Debuts New Generation Of Four-Cyindler Diesel Engines | eMercedesBenz - The Unofficial Mercedes-Benz Weblog

 

[tangey]

Anyway, a peak is just that. It has no span.

The table in the original article which was linked to in the first post, would indicate that is not the case. One engine remains at peak over 800 rpm range, the other over a 1400 range

 

[mgooda]

Am I right that a new 6 cylinder diesel is also on the cards, OM656??

 

[grober]

Am I right that a new 6 cylinder diesel is also on the cards, OM656??

Correct- the OM654 and OM656 are part of a modular series of 3,4,6 cylinder inline turbocharged diesel engines. I believe they are bringing out a similar series of petrol fuelled engines.

 

[Bellow]

The table in the original article which was linked to in the first post, would indicate that is not the case. One engine remains at peak over 800 rpm range, the other over a 1400 range

The deviations at below and above the quoted rpm range must be when the torque drops to a mere 399 N.m. Possibly (for marketing reasons) 400 is their magic number.
The graph shows the torque curve to be essentially flat for 1500 rpm though.

 

[grober]

some pics here- altho most consist of guys in suits! This happened at the end of 2014 indicating just how long an engine development program takes before they hit the streets.
https://daimler.portal.covisint.com/web/portal/supplierforum_om654_656

 

[Bellow]

...... indicating just how long an engine development program takes before they hit the streets.
]

Diesotto?

 

[nick mercedes]

MB do seem to let themselves down in the deisel department. They are well behind Audi & BMW in regards to engine choices.

Aren't most of the newer engines just Renault engines in disguise?

 

[grober]

Couldn't say. The smaller cam-belted 1500cc diesel found in some models is a Renault engine and Renault contributed to the development of the new FWD A class and spinoff derivative platforms. My guess is this new modular diesel is a Mercedes design as it forms the basis for a family of in line diesel engines, but who knows Renault may have had a strong input at various stages?

 

[JBD]

MB do seem to let themselves down in the deisel department. They are well behind Audi & BMW in regards to engine choices. (IMO)

Strange that this criticism is so publicised and yet they fail to be listening.

Mind you, what do I know???

Ant.

Not sure this is right. Surely developing a whole new Diesel engine lineup is listening

 

[C240Sport97]

when does the new 2 litre diesel being launched in the new E class make into the GLC?

 

[JBD]

when does the new 2 litre diesel being launched in the new E class make into the GLC?

I spoke to head office the other day about this after a customer asked the same question. The GLC product team said it will be at facelift in 2018, so not soon. There was a rather large overhaul of the current engine for the GLC, so I don't think it's necessary.

 

[gIzzE]

3....all the elements of the exhaust aftertreatment system are now configured directly on the engine itself and no longer on the vehicle.

Is it a great idea to build things like DPFs into the engine itself?

I would be interested to see the procedure for replacing it when needed.

 

[Bellow]

More onto than into I think.
This more about having all the kit then the exhaust system where before elements were within the exhaust system. The reason will be to minimise upstream heat loss so that the elements gain temperature as fast as possible from start up.

 

[grober]

It also may make it easier to fit the engine plus emission control elements into different vehicles as designers have a fixed volume unit to work with?