nobody: MB engineers: *smokes blunt* " hey, lets put timing chain on a back of Engine and also lets put Fuel pump on back side of engine. That would be hillarious"
+Chris Comley breat to drive but you wouldnt want the cost of owning one when the timing chain gives issues! they have really messed up what would be a fantastic engine with 2 simple things. timing gear at the rear of the engine instead of the front, and having a single timing chain instead of a duplex (double) chain.
Same principle as bmw's N47, chain behind, same place of the starter, same place of the high pressure pump, balance shafts, om651 just a copy of the N47
Plözlicher Motorschaden bei w204 220 cdi 190000km om651 trotz regelmäßigem service, nie wieder mercedes, bereue jetzt dass ich von bmw auf mercedes umgestiegen bin
@@CxBattalCx that is some dirt in the engine it would cause only one problem conecting rod bearing better check who touched your engine oil cap and dipstick
worst mercedes diesel engine ever in terms of reliability and maintenance/repairs. timing chains (in the UK at least) fail regularly on them, because theyre single not duplex chains like their predecessors, as do tensioners fot the chains. plastic water pumps are known for failing at as little as 30,000 miles, and the timing gear is fitted at the GEARBOX end of the engine, meaning that instead of being a relatively minor job of removing the timing cases etc from the front of the engine while the engine was in situ, like the older OM646 and 611 engines, its now an engine removal job to fix the timing chain faults! some have been seen to fail at as little as 80,000 miles and NO WARRANTY offered on the job in the UK despite the older engines running needing no attention for 3, 4 or more times this mileage!
+Peter Lattimer The chain being at the flywheel end is actually *very* good engineering. 1) It allow the front end of the engine to be more pedestrian friendly in an impact 2) As the flywheel end of the crank is not subject to the same torsional vibration as the free end, the chain has a *much* easier life as does the cam. Many large engines have cam drives at the flywheel end for this reason - older MB truck engines did this (I'm thinking of engines like the OM442 14.6 litre V8 which had a flywheel end gear drive to the cam in the centre of the vee) The balance shafts are the two small gears at the lower end of the gear train, they will run at twice crank speed in opposite directions to each other, as the 4 cylinder engine's main imbalance is the secondary vertical forces. In terms of winding a new chain into the engine, I can't see that it makes much difference to the job if the chain is at the front or rear, but, if there's gross wear and the chainwheels themselves need changing, that will be a difficult job - hopefully, MB have got the material spec for these chainwheels right.And a single row chain will survive becase of the significant reduction of torsional vibration in its power source, Going the whole hog with a silent or hevo chain might have been even better though.
you seem to be missing the point im making, certainly in the case of the OM651 and im almost sure these will suffer the same fate in that its NOT a case of merely winding on a new chain. the chains actually SNAP they also wear the chain guides meaning that the chains rattle before they snap, and there are cases of cam chainwheels breaking up on the OM651 also. the OM651 is proof if it were needed that a single chain isnt up to the job, and whilst theyre tested to huge mileages, in test mules etc, they rack up the miles in a very short space of time. here in the UK at least, many cars can reach 10 years old before they reach 100,000 miles ie the private buyer, rather than fleet buyers. it is these private buyers who have these issues with chains snapping and it is those same private buyers who will avoid buying mercedes vehicles for their personal or business use, and it will eventually have the knock on effect that the reputation for reliability issues will be widely known and fleet buyers will also avoid the brand because the potential for large bills becomes too great. the chain should be a duplex or even triplex chain as a minimum, or relocated back to the front of the engine where it has always been in the reliable mercedes engines. as for the big truck engines running with the chain at the flywheel end of the engine, im pretty certain those engines also dont have what is little more than a bicycle chain driving all the important and expensive parts. owners in the UK have had bills for £5,000 to repair OM651 engines sue to timing chain issues on cars barely 4 years old in many cases which, on what is supposed to be a premium marque, the slogan of which translates as 'the best or nothing' i find unacceptable. it is, like the rust era of the late 90s and early 2000s a classic case ofcutting costs at the cost of quality
Where are these OM651s with snapped chains? I see none in my garage. Literally not one and we look after hundreds. The chain is short and not under huge loads, driving only the cam. The rest is gear driven and very well designed. What I do see on the engine however is ancilliary items such as plastic fuel filter housings beginning to break up due to heat at relatively modest mileages. Remember that this engine in various forms powers dozens of different MB vehicles. everything from the new A class to the E and sprinter and vito vans too. There must be hundreds of thousands out there, many with huge mileages (we see commercials here with in excess of 250K and some private cars with similar) with no reported issues. If there was a genuine problem it would be more than this hearsay going around. It would be a full scale recall or legions of unhappy owners along the lines of the piezo injector recall on the same engine a few years ago. But that just isn't happening, all I see are happy owners generally. Now the BMW N47 engine is a case of an engine having a genuine issue with the timing gear - thousands of affected cars and all the ensuing hassle. I respectfully disagree with your opinion that a single chain isn't up to the job, my experience proves otherwise and from a technical engineering standpoint, the set up is very good. Duplex would be used if the chain were longer and driving pump/crank etc but in the 651 the lower load and short chain length means simplex is fine. I repeat, I have yet to see one snap in service. As to cost cutting, the helical gears on the bottom of the engine are the expensive way to do it and are very well executed on the 651. I have seen this part of the engine in the flesh and it easily betters anything BMW or VAG are currently doing in their engines. Very, very nice quality that I would be extremely confident of achieving big mileages.
+stevepising high mileage engines don't see the issue as much as low mileage ones. there are plenty of chain and chain wheel issues in the UK. the forums are full of them. very few would advise buying an OM651 engined vehicle here, and would suggest that an OM646 EVO engine is a much more reliable power unit.
Don't forget the 651 was introduced in 2008. I have customers who have been running early 651 s at 10-15k a year with no issues in this area. These are now pretty old cars with around 100k or less. I tell customers who are interested that with a chain cam engine to make absolutely sure that the oil is always changed on time and there should be no problems. So far - no snapped chains or even rattly ones. As I say, there just aren't the problems that people are saying there is. As for the forums, well you hear lots of things on them. Take with a pinch of salt I think. There is much scaremongering out there by people with agendas and as always I prefer to get my info from the real world from the people with direct experience. I will stand by my comments above and say the OM651, while not without a few small issues is a good engine.
That's a too short presentation about this engine! What about the low- and high pressure oil circuit? And what about the oil valve, what blocked in a lot of engines and destroy them? Because the low oil pressure destroy the whole crankshaft line! We owerhaul in our workshop a lot of 651 engines with the same crankshaft/oil pressure problem!
@@PumpUptheJam81 Hi Luke! Yes...after we overhauled the first 3-4 engine like this...and the issue continue persists, we realized what was causing the problem. We replaced the valve (with sensor) in the oil circuit with a simple aluminum plug...with this method we increased the oil pressure in the engine. We tied the old valve with sensor to the engine and pluged in the sensor, so the engine control system has no errors. Before you buy the Sprinter with this engine...you have to check the oil filter cartridge! If in the filter's layers are iron filings, it means that the line from the crankshaft is ruined (game over :-) )
@@vanyiszabi Hi there! when you say Oil you mean the pressure for the diesel lines? I have a C207 250CDI from 2011 (the one with the 5 speed gearbox) it had just 72000 km and the engine was destroyed. No idea how it happened. The mechanic suspected overheating (without any warning in the dash) a water line dislodged and engine was stuck now now no idea if the water line was dislodged while driving or at the end while parking (saw smoke and then the car shut off) I was getting the error P0087 Powertrain which has to do with not enough pressure for the diesel which happened only when hitting the pedal gas fully down (kickdown) car was entering in limb mode and after restarting the error went away. I was never doing this since it happened and car was fine until the engine was dead. Now we have replaced the engine with one from UK which had only 25k miles (end of 2015 model) The mechanic used the oil pump from new engine, injectors from new engine, oil cooler from new engine but he used my own turbo since he said it was different the new one. I went to a tune up shop to check the HP and it was much less than stock around 190 Engine power instead of 204 . The guy at the tune up shop said something about the turbo maybe losing some air in the flaps. Also the error it came back! the oil pressure error i mean! how is it possible with a new engine and new pump etc etc.
After 250 000 ready for trash. I have changed 3 engines in my c klass 2011 two of them and one in Sprinter . Camshaft wich has to much movement left to right 0.4 millimeter when it comes from production is simply stupid from Mercedes factory. OM651 has lots of problems try to find 320 or even petrol 1.8 wich is much more reliable .
