What 642 will work?
 

Vehicle in question is a 2009 ML320 that has a bad engine. What years and models of the 642 can be used as a replacement? What would be a direct replacement and what might be used as replacement with swapping components. When I look on car-part they seem to pull of ML and GL vehicles, but not 211 e class. Will an e class engine not work for some reason? I noticed the prices on the ML/GL engines seem QUITE a bit more expensive than the 211 version for some reason. I am going to look at one this afternoon that appears to be in decent shape that I can probably get for around a grand. Supposedly it was run out of/low on oil and supposedly will start with a battery. If that is the case and it will crank and start, it must not have been run completely out and probably now has a bad knock. I am not sure if I am crazy or not thinking about taking on an engine swap 642 project.

What failed on you engine?

Off the top of my head there are many differences such as
Cylinder heads
Engine mount bolts either 8 or 10mm
Ancillary brackets will not fit certain models
engine wiring harness plugs differ
Starter motor can be mounted either left or right
Its the last 3 digits of the engine code you need to match up to ensure it will fit.

These om642 engines knock out number one main bearing if you neglect engine oil changes so the one you are going to look at in reality is not a feasible option unless you intend to completely strip it out and rebuild

https://www.motorreviewer.com/engine.php?engine_id=175

It is used in many cars, Chrysler, Jeep, dodge, sprinter, mercedes including the w211. There should be plenty around. Good luck.

I have no idea what the extent of the damage is. I have not seen the car yet but the current owner says he had it in for service, then left for a trip and it ran out of oil. He says it still will start with a battery so I am not sure. All I can do if I guy it is to get a battery in it and try to start it see what happens. I am going into to the deal planning on just swapping the engine, if I buy it at all. Has around 170k on it.

Yes there are plenty around but there are minor to major differences depending on what model they are installed in.

So against my better judgement I bought this 2009 ML320 Bluetec today for $1k. Guy who owned it said he had the oil changed about 2 years ago (truck has been sitting since), then left for a 4 hour road trip. He says suddenly it starts acting strange and he pulls over and its got a loud knock. He says he checked the oil and the dipstick was dry, never got a low oil level warning. He says he put oil in it then had it towed home. I show up today, throw a battery in it and it fires right up but sounds like a rod is about the go shooting out the side of the block. I load it up and bring it home. When I get home, I made this video while on the trailer, then after unloading it. Just watch the video and you will see what I mean. What the heck is going on with this thing?

https://youtu.be/XVt12FnCSJE

At beginning of video one of my first thoughts were ok rod knock , this then changed to bad injector due to seal or possible injector tip causing knock.... at the end of the video i’m thinking hydraulic lifter / followers problems.

I own 4 OM642 powered vehicles, and each one has its own unique variant of 642.

The basic things are in the same places but a lot of differences in minor bits.

The two SUVs definitely have much different oil pans than the sedans, probably to accommodate the front half shafts from the transfer case.

My kids 2008s (one a ML320 and the other an E320) the sedan dipstick is in the back left corner but the SUV has it on the front right.

Definitely different oil pans.

But from the top they look pretty similar at first glance.

If you really did lose lubrication it’s probably not worth trying to save the engine.

If you do swap engines remember that the injectors are coded with the ECU so either keep the old injectors (and label them in their positions, the cylinders go like this front to back)
3 6
2 5
1 4

Or have access to Xentry to be able to put the code numbers from the new engine’s injectors into your ECU. You won’t be able to run the donor engine’s ECU on your vehicle’s system, the DAS (drive authorization system) won’t do the happy dance with the unrecognized ECU vs. the instrument cluster, central gateway, and VGS (transmission controller in the valve body).

If you have access to EPC it should give you the 642.xxx number of the subject vehicle, and then if you go and do a search on the part number for the complete engine it should tell you the ‘where used’ on all models.

Hooked das up and check engine codes were not related to injectors or cylinders. When I started it up the knocking was back, which then went away again. I noticed it I revved it up a bit the knock would come back then go away again after a few minutes. After it quieted down again I was able to rev it to about 2500 and it was smooth and quiet. Later on the noise came back and a couple of times I got that screeching noise that sounded like the belt. I am wondering if it was the belt or a bearing spinning? At this point the car is at operating temp and the noise is consistent. I went into activations to shut off injectors one at a time and it seemed to me like #4 made no different in its idling condition. A miss seems to accompany the knock, which makes sense. When I shut #4 off it ran the same but still knocked the same. I then went into the values for what I believe to be injector flow rates and it seems to me #4 is way off from the rest. If it was injector knock, i would think shutting off each injector would eliminate the bad one.

I am not really sure how to read this but take a look at the screen shot and see if it tells you anything? Nevermind can't seem to attach it. Here are the results
#1 -1.32 mg/hub
#2 -2.19
#3 2.06
#4 5.08
#5 -2.50
#6 -1.15

I’m still not sure if it’s just an injector or a rod knocking. If it is a rod, can the engine be pulled and the crank pulled and replaced? Or would the engine be toast?

Despite being turned off there is still fuel rail pressure acting on injector

Now that I think about it that could be true. If the injector was stuck open it would not matter if you shut it off or not, fuel would still be streaming out when it should not be.

What about this scenario

Injector fails open, dumps excessive fuel in cylinder

Either the cylinder hydro locks, bending the rod, or a hole gets burnt through the piston

Oil sucked into this cylinder and consumed by the engine thus explaining the oil loss.

(Is there a big oil stain on the bottom, if the oil leaked out the plug going down the highway you would be oil coated all the way under to the back bumper)

I would pull that injector and get a bore scope in the cylinder before going further. It sure sounds like this engine is toast to me if this scenario is what happened.

Horrible way for an engine to die

Its capable of running smooth and quiet so change that injector and see how it runs .. it may need the injector coding to get the best out of it but it may be all it needs to fix it.

I have had an injector go bad on my 06 Jeep GC om642 , chucking clouds of smoke out at tick over ( bad nozzle) rev it to over 1k and smoke would stop and it was smooth as could be. But it bucked and shook at normal idle speed and pinged /knocked /rattled and had to be put in neutral at lights

I may need to see if I can find a cheap or reasonable priced injector around. Depending on how big a pain they are to pull, I could pull one or more out of my 07 R320 that is sitting waiting on the oil cooler seals to be replaced. I kind of hate to do that though but it might be the best way to see if it really an injector or not. Engine appears to be clean and nothing leaked out of the trailer. I do not think a piston is holed because it is capable of running smooth and quiet. I might pull the oil filter too and see if there is any metal shavings in there. I am still not certain if there was actually oil loss or not. If the PO really did not get a low oil message, I would think there was actually not any oil loss, but no telling.