Engines

Mercedes-Benz OM642 engine (2005-on)



Available from 2005, the Mercedes-Benz OM642 was a 3.0-litre V6 turbo-diesel engine which replaced the five- and six-cylinder OM647 and OM648 engines.

Manufactured in Marienfelde, Berlin, and Stuttgart-Untertürkheim, the 2987 cc OM642 engine had 83.0 mm bores, a 92.0 mm stroke, a 72-degree ‘V’ angle, an aluminium block and cylinder head, common-rail direct injection (operating at up to 1600 bar) with piezo injectors each with eight injection nozzles, a variable geometry turbocharger (VGT or variable nozzle turbine, VNT), double overhead camshafts (duplex chain driven), compression ratio of 18.0:1 and a diesel particulate filter. Furthermore, the OM642 engine had a counter-rotating balance shaft between the cylinder banks.

In early 2014, Mercedes-Benz’s ‘Nanoslide’ cylinder wall coating was introduced for the OM642 BlueTEC turbo-diesel engine for greater fuel efficiency and mass reduction.

Engine Capacity Peak power Peak torque Model Years
OM642 DE 30 LA red. 2987 cc 140 kW at 4000 rpm 440 Nm at 1400-2800 rpm W164 ML 280 CDI 2005-09
W164 ML 300 CDI 2009
W211 E 280 CDI 2005-09
W251 R 280 CDI 2007-09
W251 R 300 CDI 2009-12
150 kW at 4000 rpm 500 Nm at 1400-2400 rpm W164 ML 300 CDI 2010-11
W212 E 300 CDI 2010
W639 Viano 3.0 CDI,
W639 Vito 120 CDI
2006-10
OM642 DE 30 LA 2987 cc 155 kW at 3400 rpm 540 Nm at 1600-2400 rpm W164 ML 350 BlueTEC 2009-11
X164 GL 350 BlueTEC 2009-12
W211 E 300 BlueTEC 2007-09
W212 E 350 BlueTEC 2009-13
W251 R 350 BlueTEC 2009-12
W463 G 350 BlueTEC 2010-on
OM642 DE 30 LA 2987 cc 165 kW at 3800 rpm 510 Nm at 1600 rpm Chrysler 300C 2004-10
OM642 DE 30 LA 2987 cc 165 kW at 3800 rpm 510 Nm at 1600-2800 rpm /
510 Nm at 1600-2400 rpm
W164 ML 320 CDI 2005-09
W164 ML 350 CDI 2009
X164 GL 320 CDI 2006-09
X164 GL 350 CDI 2009-10
W203 C 320 CDI 2005-07
W204 C 320 CDI 2007-09
W204 C 350 CDI 2009
X204 GLK 320 CDI 2008-09
X204 GLK 350 CDI 2009-10
A209/C209 CLK 320 CDI 2005-10
W211 E 320 CDI 2005-09
C219 CLS 320 CDI 2004-09
C219 CLS 350 CDI 2009-10
W251 R 320 CDI 2004-09
W251 R 350 CDI 2009-10
W463 G 320 CDI 2006-09
W463 G 350 CDI 2009-10
W639 Viano 3.0 CDI,
Vito 122 CDI
2010-on
OM642 DE 30 LA 2987 cc 170 kW at 3800 rpm 540 Nm at 1600-2400 rpm W164 ML 350 CDI 2010-11
W204 C 350 CDI 2009-11
W204 C 300 CDI 4MATIC 2011-13
X204 GLK 350 CDI 2010-12
A207/C207 E 350 CDI 2009-11
W212 E 350 CDI 2009-10
W212 E 300 CDI 2010-11
OM642 DE 30 LA 2987 cc 173 kW at 3600 rpm 540 Nm at 1600-2400 rpm W221 S 320 CDI 2006-09
W221 S 350 CDI 2009-10
OM642 DE 30 LA 2987 cc 170 kW at 3800 rpm 540 Nm at 1600-2400 rpm W212 E 300 CDI 2011-13
W212 E 300 BlueTEC 2013-on
OM642 DE 30 LA 2987 cc 185 kW at 3600 rpm 620 Nm at 1600-2400 rpm A207/C207 E 350 BlueTEC 2013-14
W212 E 350 BlueTEC 2013-14
C218 CLS 350 BlueTEC 2013-14
OM642 DE 30 LA 2987 cc 190 kW at 3600 rpm 620 Nm at 1600-2400 rpm W166 ML 350 BlueTEC 2011-on
X166 GL 350 BlueTEC 2012-on
A207/C207 E 350 BlueTEC 2014-on
W212 E 350 BlueTEC 2014-on
C218 CLS 350 BlueTEC 2014-on
W221 S 350 BlueTEC 2010-13
W222 S 350 BlueTEC 2013-on
OM642 DE 30 LA 2987 cc 195 kW at 3800 rpm 620 Nm at 1600-2400 rpm X164 GL 350 CDI 2010-12
W204 C 350 CDI 2011-13
X204 GLK 350 CDI 2012-on
A207/C207 E 350 CDI 2011-13
W212 E 350 CDI 2010-13
C218 CLS 350 CDI 2011-on
W251 R 350 CDI 2010-12

OM642 Engine Problems

Knocking or ticking noise at idle – crankshaft main bearing

In February 2013, Mercedes-Benz issued Service Bulletin LI03.20-P-048278 for Mercedes-Benz models that had OM642 diesel engines. According to LI03.20-P-048278, these vehicles may exhibit an intermittent knocking, ticking or knocking noise at idle and at engine speeds up to 1500 rpm. Specifically,

  • The noise would occur after a mileage of approximately 32,000 kilometres or after an oil change;
  • The noise could be clearly heard in the area of the first crankshaft main bearing;
  • The noise would not be present when the poly-V belt was removed;
  • The noise was a pulse-like crackling that occurred at irregular intervals; and,
  • 20 pulses (ticking) represented a ‘justifiable complaint’.

These symptoms were attributed to a ‘run-in effect’ or defect of the first crankshaft main bearing shells. To verify the complaint, the poly-V belt was to be removed to see if that eliminated the noise. To fix, the bearing shells of the first crankshaft main bearing were to be replaced.

Oil cooler leaks

Pre-2010 OM642 engines were susceptible to oil cooler leaks due to heat-related seal degradation. In 2010, Mercedes-Benz introduced more durable Viton seals which could be identified by their purple colour (the previously used seals were orange).

TWC temperature sensor

The TWC temperature sensor (part no. A005 153 40 28) was susceptible to failure and was subsequently replaced with part no. A007 153 74 28. When the temperature sensor fails, the check engine light may illuminate and issue the OBD-2 diagnostic code P2031.

Swirl valves, blown fuse and ‘limp home’ mode

The positive crankcase ventilation system vents to the inlet of the turbocharger. However, the vented air may contain too much oil to easily pass through the swirl motor valves which are downstream of the turbocharger. Once this oil and sludge begins to accumulate, the swirl motor valves may become inoperative and blow a fuse that controls other sensors which are required for the engine and emissions systems to operate properly. As a result, the vehicle will enter ‘limp home” mode and limit engine speed to 3000 rpm.


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