In reply to Davesvo :
Full disclosure: I'm a complete hack and am basically making this up as I go along. Like the old bumper sticker says, "don't follow me, I'm lost too!"
With that disclaimer, I would consider going ahead and doing the crank and rod bearings. You don't have to worry about using a sub-standard replacement since nobody makes them except Kobelschmidt or whatever. I know it adds a few bucks, but if you're going all that way anyway...
First time poster, long time reader of GRM magazine and forums.
Why, you ask? What could possibly drive you to post after all this time?
Another Weiß Shiesse Wagen, of course!
We bought this 2010 W164 ML350 to tow our small camper trailer. It works fabulous as both a small tugboat, and a runabout when unhitched. But it has one small problem. It has an appetite for the 'stuff'. You know, the slippery stuff. M-B approved motor oil. She's hooked on it, doing a quart in only 200 miles, then throwing a recurring code for too frequent DPF regen and restricted DPF. So it's time for the intervention. The usual: Teardown engine, decarbonize pistons, replace rings, clean out oil sludge, etc.
The pic shows about where I'm at today, engine is almost ready to come out. My question for the hive mind is: Does the tranny really need to be dropped before engine removal? WIS clearly says to separate trans and remove, then pull engine out the top. I've never had to do that on a modern car, only antiques where the trans doesn't have a mount.
Thanks for starting this educational thread, and thanks for any info or tips on engine removal.
In reply to FJ40Jim :
Welcome to the excrement exhibition!
I don't know about the ML, but WIS says I have to remove the trans on the GL in order to pull the engine. I disregarded that instruction and simple unbolted the trans and torque converter from the engine and flywheel, respectively and der Scheißmotor came right out the top, no problem. With the hood in the service position and the core support crossmember removed, there was plenty of room to bring the motor forward and out. Now, I did put a jack stand down there to support the bell housing side of the tranny, and I think I used a floor jack to support it and fiddle with the angle to get the motor separated.
Good luck on your adventure! Are you going to do new valve stems and seals as well, or is it all blowby for you? How many miles do you have on the old girl?
Thanks for the info, WAE.
FWIW, the ML (W164) and GL (X164) are pretty much the same, except for the Xtendedness of the GL that allows for 3rd row seating.
So yeah, I went ahead and removed tork convertor bolts & bellhousing bolts, then picked up engine off mounts and it just slid right apart from bellhousing. There is a small bottle jack holding up the front of the tranny to keep it in roughly the correct position. Engine came out easy, it was getting all the stuff disconnected that was time consuming.
The vehicle has 160K on it, but the paint, interior and undercarriage all look very good for the miles, which is why I'm fixing the engine. The turbo has minimal play in it, the centrifugal oil separator on the back of the head is in good shape, the oil filter had no sludge in it. There is no obvious smoking gun for oil consumption. Engine is on stand now, exploratory surgery will happen this weekend. First I hafta churn through some customer pay work to be able to afford this rebuild.
Todays progress:
And a pic of happier times earlier this summer when we first bought the trucklet and didn't realize how much oil it was using:
In reply to FJ40Jim :
They're good looking, aren't they? And I'm betting it towed that camper like a dream, too! I'm anxious to hear what you find when you crack your Scheißmotor open!
For mine, I'm going to receive 2 new exhaust valves, 2 new intake valves, and the head install kit this week some time. After going back and forth with the whole bolt situation, I decided to not take a chance with it and just ordered up 16 new bolts from AutohausAZ. They're a little less expensive on the bolts than idparts. I'm taking tomorrow and Friday off work, so I want to start cleaning things up and getting stuff ready for reassembly. I also need to take a good look at the oil pump and see if it got damaged by the bearing material that was coming loose.
Excited to see this coming together. The GRM Forum will earn the honor of repairing TWO overcomplicated Mercedes minivans. 
Tom Suddard said:Excited to see this coming together. The GRM Forum will earn the honor of repairing TWO overcomplicated Mercedes minivans.
Hey now! According to the title, mine's a station wagon!
In reply to FJ40Jim :
Welcome to the madhouse, Jim! Good to see you here.
Today's first step was to make a determination about the oil pump. I was pulling big ole chunks of metal out of the block, so the chance that those chunks made their way through the pump was pretty high.
I dug out the bins of parts and took a little safari through plastic baggies and stuff and finally found the pump. They say that things are always in the last place you look and in this case that was true... but it was also in the second and fifth places that I looked. Apparently I was remembering the size of the pump incorrectly and looked right past it twice. That problem solved, I broke out the E10 socket and zipped the three bolts out so I could get a good look. Once it was open and I could see the impellers and inside of the housing, it wasn't great news:
Not a fan of how that looks. Looks like I'm going to go ahead and order up a new one. The good news is that I can continue on and just come back to the pump later once I have a chance to get it in.
So I spent some time cleaning instead. Right head valve cover gasket surface is ready.
In reply to Tom Suddard :
There is a minivan built on this midsize platform:
In reply to wae :
The oil pump housing would be OK to run. The problem is the gears that have processed metal. The wear is quite visible on the drive faces.
On some crude engine (domestics) the gears can be flipped over in the pump so that the unworn coast sides of the gears are making contact, effectively yielding a new pump. Prolly not possible on this unit, because M-B.
My tech question of the day: The turbo on my engine has some play in the shaft. Minimal detectable endplay (guestimated .003-.005") but the radial play seems excessive at .015-.020".
The craptabulous WIS has no service/wear specs for the turbo.
Digging around in the stash, found the FSM for Volvo/VW D24T 6cyl turbodiesel. It specs a max of .020 radial clearance, which sounds huge, but maybe makes sense at 100k RPM. And the blades of either wheel come close, but don't contact the housing.
Thoughts?
In reply to FJ40Jim :
With the caveat that I am far from an expert, my understanding was always that you should expect more up-and-down movement on a turbo than in-and-out since you can only try to measure the axial clearances when there isn't any oil pressure. It's weird to me that they don't list any specs in WIS, though. Even if there isn't an official M-B overhaul parts list for the turbo, you would think that they'd have a value to check for to trigger selling a whole new $4,000 turbo.
As far as the minivan is concerned, there's a well-documented saga of the AMG version of those here on this very forum. In fact, that's what fed my hubris into thinking that I could tame one of these things in the first place. It's a great read: https://grassrootsmotorsports.com/forum/build-projects-and-project-cars/r63-amg-the-unicorn-of-my-destruction/110824/page1/
I think the turbo is fine with that play. the radial I would not worry about at all. the end play sounds good at .003" to .005". Typically the radial play is pretty big with no oil pressure. I go with if it's not hitting the housing its good this could be wrong but that's what I do.
On a separate note, While reading through the Mercedes WIS I see a note on Connecting rods needing to be replaced after removal (or opening) due to dimensional accuracy. What are your thoughts on that? I know you replaced at least one rod, did you measure the big end on the others for out of round?
In reply to Davesvo :
I put the rods back together with the original bolts - excuse me, with the original assembly locking elements - although I don't think I ran the full torque sequence on them. I think I just brought them to "snug-with-a-3/8-ratchet" for fear of snapping the used "locking elements". I used my bore gauge to check roundness and found that the #2, which was the one that was banging around, was definitely a bit ovoid, but the other 5 were still pretty round. I don't recall off the top of my head what measurements I got on them, but I recall that it didn't move the gauge very much.
If the rods weren't $300 each, I'd be more willing to entertain the possibility of replacing them.
IIRC turbos with journal bearings have a floating shell between the inside and outside, which cuts down a lot on the relative speeds going on in there. This also means there is twice as much play when there is no oil pressure, because there are two oil clearances not one.
You're also measuring really far away from the bearing, relatively speaking.
That is why it generally boils down to "if the wheel don't scrape, it's good"
I've had some other stuff going on that's been keeping me away from this, but I've been getting a few things done.
Parts: I've got new valve seals coming in, the head kits are here, and the second new set of crank bolts have arrived. I think I need another cylinder's worth of valves because as I'm looking at piston #1, there's positive evidence of the exhaust valves having been in contact.
Tools: A little birdie told me that I'm getting a valve spring compressor for Christmas, so that'll be cool. I also picked up an angle gauge so I can properly follow the torque procedure. I also brought the parts washer out to the shop, put it on wheels, added a bucket warmer from Tractor Supply, and filled it with Oil Eater. I put in two gallons of the stuff along with 6 gallons of water and it's not really enough to submerge the pump all the way. But I'm not sure that I want to add any more to the tank now because after running a few parts through, it's pretty black.
Cleaning: I filled the right head's intake side with brake cleaner and got in there and scrubbed as best I could. It was just completely nasty and full of carbon. Once I get the valves out, I'm going to run it through the parts washer and scrub away some more to get the rest of it cleaned up. This is most of the carbon that I got out of the intake side of the right head:
Notice the brake cleaner leaking out of the intake valve. I suspect that the valves are nastied up with carbon and not sealing all the way. I'll clean those up and give them a little lapping compound.
I also put the intake manifolds in the washer. Talk about nasty:
Here's the other one:
Look at all that carbon built up in there. Naturally that interferes with the swirl flaps, not to mention that it's constricting the airflow and putting a bunch of crap into the combustion chamber and crankcase. I neglected to get a good "after" picture, but most of the junk is out of there. There's still a bit, but I think a bottle brush that you'd use to clean out a carboy will work pretty well to scrub it the rest of the way.
Regularly scheduled progress: Well, take a look at these:
That is the crankshaft installed and fully torqued. Not all frozen up this time, either!
I also managed to get the #1 piston installed before I was too tired to go any further.
wae said:In reply to Davesvo :
If the rods weren't $300 each, I'd be more willing to entertain the possibility of replacing them.
I'm probably a little late on this but it could be possible to have the rods resized. They cut the mating surfaces and bore/hone a new round hole.
In reply to Jerry From LA :
You can't cut the mating surfaces of a fractured rod, the fracture point is what locates the cap.
One CAN get oversized bearings, but I bet Mercedes does not offer them if they tell you to replace the rod. The aftermarket does make them for some engines, generally for rebuilders. It makes little sense for a home rebuilder to pay a shop to resize the rods and then buy some expensive specialty bearings if it is just about as cheap to just buy new rods, sometimes cheaper. A rebuilder can just set the new guy in front of the rod hone with a pallet of old rods and let him go to town 
WAE, I'm glad you are making some progress!
Don't want to hijack your thread but I thought this info might help someone else who finds this thread.
I did pull my engine completely apart and did a full inspection. The oil control rings on mine were fully packed with carbon and stuck in the grooves. I have never seen a piston so carboned up come out of a running engine. Upon inspection all the cylinder bores looked great until i put my bore gage in them and started measuring. They were all right at the top limit of dimension and out of round except 1, cylinder number 5 is .002" out of round at the top, and even though that is not much the WIS says Max is .007mm or .00027". So if this was just a sbc or ford I would have honed it and run it... this thing needs bored and oversize pistons. Then there is the heads, the exhaust valves stems look ugly and the rockers match, also the lifters look ugly where they sit in the heads, so to do it right I would need to have the heads done and new valves put in, new rockers, new lifters etc. After adding this all up I started to look at what my options are. Started looking into remans or used engines. As we all know used engines are ridiculous for something that may be just as bad as what we have. So kinda as just a lets see how Proud MB is of this engine I called my local dealer for prices on engines. Turns out MB now has reman engines in several flavors from long block all the way up to complete engines. The best deal is on what they call a Basic engine, as it comes as a long block with new injectors and oil cooler, just need to swap intake, exhaust manifolds turbo, wire harness, vacuum pump, high press pump and any other bolt on stuff. The surprise? Price, out the door with tax was under 8k with a 4 yr 50k mile warranty. I know that sounds kinda expensive but after adding it all up to fully rebuild mine and the chance of missing something or having a failure that i'm on the hook for it does not make sense for me to rebuild this one. My new "basic engine" will be in tomorrow.
In reply to Davesvo :
It's certainly a lot less work and, like you said, fewer opportunities to screw things up. That doesn't sound like a bad price, considering. I think I worked out that if I were to put in new "everything" - pistons, rings, rods, bearings, oil pump, timing, seals, valves, gaskets, etc. - it would be about $6k. So another 2k to have it done for you and get a warranty sounds like a fair price.
One thing about my engine is that while the intake is just full of carbon and nasty, the valvetrain was relatively clean. I'm guessing that maybe your engine might have stretched the oil change interval even more than MB recommends?
In reply to wae :
Your numbers are right on with what i priced out to do the whole thing, just about 6k. I also can't have this thing apart for several months and the machine shop i trust is backed up for 2 months, MB had the reman in the warehouse so that was also a factor for me.
I am not the original owner we picked it up at about 85K on the clock. I did oil changes every 5-8k from that point on, but i have no idea what happened before me. Issues started with a clogged DPF and limp mode out of the blue. after that Noticeable oil use started this all happened at about 115k. I kept cleaning the dpf and chasing the oil issue until now at 125k I just can't trust to let the wife take it anywhere. I did not expect to see the wear on the valve stems or rockers, and it's only on the exhaust valves the intakes look perfect. I have my doubts that it is a oil issue as the rod and main bearings literally look brand new, as in I would have put them back in with out hesitation, not even scuff marks on any of them. Cams, followers on the rockers and cam bearing surfaces also look perfect. Timing chain I believe has some significant wear as the molded plastic on the crank sprocket and the balance sprocket is worn down and chipped off in several spots, the chain is also very sharp on the edges indicating some wear. I'm fully blaming the emissions system for this engine failure, just not sure how to stop it from happening again. I am definitely considering not using the MB recommended emissions system protection oil, I may go with a regular hd diesel oil maybe Amsoil. I just need to find out from MB what they require for service documentation to honor any warranty that might come down the road.
It's really a shame, if that one cylinder had been in line with the others I would have ball honed it and threw new rings in and put it back together and done the heads.
I started putting pistons back in but ran in to yet another problem. How I missed this before, I don't know, but in addition to having its connecting rod out-of-round and its rings all beat to heck, the #2 piston is also.. dented. I don't know if it happened before or after I took it out of the engine, and I'm not sure how I walked out of the shop without getting a good picture of it, but a screenshot from a video:
So... now I'm also looking for a piston.
Since that's on hold a bit, I went ahead and started taking the head apart. Just more carboned-up, sludged-up nastiness in there. The head's in the tank right now so I can get it cleaned out the rest of the way and then replace the valve seals. I'm also collecting more evidence of valve-to-piston contact as I've re-installed the pistons, and I think there are a handful more valves that need to be replaced. Here's the "before" pictures of the right head. Keep in mind that I've already been soaking them in brake cleaner and the Berryman's spray and have gone in there with brushes and stuff to try to clean all that crud out.
Reminds me of rodding out TDI intake manifolds. I have pulled 32oz drink cups full of carbon from them, and they have very short runners and tiny plenums.
They always drove a LOT faster after this procedure!
In reply to Pete. (l33t FS) :
Mine should drive much faster, too. But then, it's averaged about 0mph over the last two and half years, so not a high hurdle to clear.
You'll need to log in to post.
