A couple questions for you if you don't mind:
-which seals weren't included in the kit?
-where are you getting the torque specs and sequences?

Looking good by the way, almost as clean as when it left the factory!

 

MartinC2S,
Several videos showed the throttle body and mixer box assembly being removed at the front of the engine. Instead of reusing the current ones, I decided to get new ones. There is a flange seal between the exit of the EG cooler that is bolted to the driver's side intake manifold. There were several other seals as on either sided of the throttle servo, which I needed to take apart to clean down stream of where the EGR gas is piped back to the intake air flow. If you have a leaky CCV valve this allows engine oil through the turbo through the intercooler to mix with EGR gas, making a very sticky mess. Removed almost a pound of this from the point they mix together and collect along the air path to the engine combustion chamber. I found the torque spec through a web link that was included in another post on this forum. I will see, if I can find the link. This included many other assembly procedures for things like oil cooler, turbo, and intake plenum.

 

MartinC2S,

This is the post where I found the torques spec for most of the items that need to be removed. It was very helpful as well as the several Youtube videos for servicing the oil cooler seals.
Instructions for Replacing Oil Cooler Seals - MBWorld.org Forums

 

@rapidoxidation "Sure seems like blocking off the EGR plumbing would be a good thing for these engines." Yes it would!

Yes, but one would need an EGR delete tune. The computer calculates raw air (MAF measurement) subtracting it from total calculated volume (MAP x 3.0 liters X RPM) continually adjusting for a target EGR volume intended.
You'll throw codes and possibly a limp mode, without deleting the EGR from the tune maps and controls.

 

I am now putting my ML350 back together, was waiting on a few more seals that I wanted to replace instead of reusing the old ones. I have mounted the air charge manifolds and have them torqued to spec and in proper order, yes there is a specific torque sequence in the MB repair instructions. I have also mounted the exhaust flap servo, which took some thinking to get reconnected to the flap linkage. What I ended up doing was turn the servo max deflection against the spring (CW). This is needed to be done so that you can connect the connection clip to the flap actuator arm on the left side. Then I released the string, letting the arm ret urn to it's home position and connecting the other servo arm connection to the right exhaust flap arm, seen in the photo below. I have also remounted throttle assembly and EGR gas mixing chamber at the front of the engine. Please note that it is very tricky to try and get the tube 'O' ring tube into 2nd tube of the exhaust gas cooler. This tube is hidden under the plastic housing that is bolted to the air charge manifolds at the front of the engine.

 

Please see last photo in the last post that show how the throttle and mixer box is bolted the front of the engine. The other end of the assembly is attached with two bolts to a bracket the is bolted to the side of the engine, see attached photo. Please note that I replace the torx screws with slightly longer socket head cap screws. Torx didn't look to have enough thread engagement?

 

Today I made good progress after getting the oil cooler, air charge manifolds, flap valve servo mounted, and throttle and mixer assembly, yesterday. Today I finished torquing the bolts for the throttle assembly, then I moved to putting the wire back in place and connecting plugs where I could. This allows you to reconnect the injector supply lines that had be moved to get the wire out of the way to remove the air charge manifold. You should remember to reconnect the (2) coolant lines that connect to the driver side charge manifold before putting the wire harness back in position. I also cleaned the mounting surfaces of the turbo pedestal. I went through my assembly notes for the torque the pedestal to the engine block. I found one reference at Peachtree, listed the torque for these bolts as (12NM) this seems low sense the air charge manifolds spec was (18NM), these were smaller bolts as well. I did find that the torque specs for attaching the turbo into the engine block spec is (20NM) and this is for the same sized bolt. If anyone may what the value for this specific torque, please forward? Would like to install the turbo tomorrow, if I get the torque spec question resolved.

 

Well I made good progress again today. I decided to torque the turbo pedestal to the higher torque value of (20NM), since that same value is used to torque the turbo to the engine block. Before installing the turbo, I changed the 'O' ring that mounts on the inlet turbo cooling tube, on the right side of the turbo. With some finagling, I got the turbo in its home position. Special note you need to be careful not to damage turbo temperature probe, on the left side of the turbo. I had to rotate the turbo 90 degrees CW to get the turbo branch line past the exhaust down pipe and the EGR actuator on the back of the air charge manifold. Once in position, I installed the (4) screws that bolt the turbo to the engine. I will leave these loose until I have the turbo exhaust branches connected to the left and right exhaust manifold. These (6) screws are torqued to an initial value of 20 (NM) and then turned an additional 90 degrees. Then the screws holding the turbo can be snugged up and then torqued to (20 NM). Once this is completed, I installed the EGR connection pipe. The last item I started to install was the connection between the turbo exhaust and the exhaust down pipe. I can get the screws to their required torque (20 NM), but not sure if I can complete the second step of turning the screws and additional ( 90 degrees ). May have to take it to the dealer to get this completed. The screws face engine bay bulkhead and they are not very accessible.

Things to Complete list
1) Install O2 probe at elbow of exhaust pipe
2) Install new CCV valve assembly
3) Install fuel rail to fuel rail connection line
4) Double check that all fuel injector supply nuts have been torqued
4) Install new fuel filter ( I will prefill filter with fuel )
5) Install charge air from turbo to front of engine and turbo intercooler
6) Reinstall injector return fuel line
7) Install air intake assembly that connects to the turbo. ( I purchased new seal for this joint )
8) Install all remaining electrical connectors
9) Install rear shield located behind turbo
10) Install new inlet air filters, left & right
11) Install the rest of the engine shielding
12) double check that all electrical and mechanical items
13) test start engine ( May take several tries as fuel lines need to be recharged )
Used a wire to install hard to access screw points

Branch tee connections to exhaust manifolds

EGR connection to EGR control valve

Exhaust Down Pipe-Turbo Exit Connection (Hole is O2 Mtg hole)

Me trying to install the (3) bolts for the turbo to exhaust down pipe and I dropped the bottom bolt ( need to find it today )

Working on turbo exhaust down pipe connection.

 

Again, Great pictures!
Thanks for taking the trouble to save and share your adventure for posterity! I know it adds to the effort.

 

B34chBum,

It has been a real adventure alright, initially I was intimidated by the task at hand and almost didn't start. I have been working on it for a while since the middle of February, even though I am retired. I did get the get the exhaust pipe attachment screws torqued with about 70-80 % of the spec. (90 deg) extra rotation, hopefully that will be enough. I should be able get it finished within the week. I will be very happy to get it back on the road again and enjoying the ride. I will try and put together a full list of items that I purchased.

One of the reasons this job is taking longer is because it Maple syrup collecting and making time in Southwestern Ohio, which means I collect maple tree sap then evaporate it down to make Maple Syrup. I collect approximately 200 gallons of sap and I might get 3 gallons of syrup.

You are welcome on the posting.

Bob Massmann

 

I got the exhaust down pipe to turbo finished connected today. I moved on and mounted the O2 sensor on the exhaust pipe. I then mounted the new CCV assembly, note that really isn't much room between it and the thermal shielding. Along with that installed the left back lifting bracket and the boost control servo that mounts to the turbo, I had removed it, in hopes it would make the turbo easier to handle. I also mounted the turbo exhaust heat shield.

 

I decided to make tools to tighten up the fuel supply lines to the injectors. I found a small offset wrench set at Harbor Freight. I then cut the tool to access the nut around the tube, see photo below. I should get close to finishing today if all goes well.

 

I thought I would post a photo of the modified tool in use, nuts are (2) different sizes (17 & 18 mm ). I was hoping to finish up the job this past weekend but discovered that the somewhere during the process I had broken the center fitting of injector fuel line. Mercedes does not sell the individual parts only the complete assembly. I was trying to get the broken piece out of the hose but it almost appears to be glued in.

Modified wrench in use

Broken Fuel return Fitting

 

I wondered whether to recommend getting the injector overflow line - I commented yesterday on another thread where poster had leak from o-rings, which I think is common.
I replaced 2 injectors last year and bought one 'just in case' and was thankful I did, because one of the circular clips was so fouled by black death soot that it really didn't want to clean up well enough to move/snap/lock but still spin, as it should.
It wasn't exactly broken, but it didn't play well with it's o-ring. I'd just let the injector seal leak go, for too long.

Another risk in this operation is dropping the little wire clip which holds the center fitting. If it falls into the valley after you have the intakes and everything else in place it could be hairy getting it back out.

As you are getting near the end, you might want to try running the motor a few minutes with the foam inserts and air filters off (plug the left one into the MAF assembly, off to the side), and check/double/triple check the connections for leaks, on this line.
It's a very fiddly arrangement, in my humble opinion - engineered for the sake of parts sales.

 

Yes, been there done that. I dropped half of the ball connector clip for the flap servo connection and it disappeared into the valley. I also dropped the bottom screw for the exhaust down pipe and turbo. I found it and tried to pick it up with a magnet, but it is none magnetic, had to use a U shaped piece of wire to pick it up. Have a new return line coming.

 

-"Torx didn't look to have enough thread engagement?"-

There's another bolt which could stand to be 1/4 to 5/16" longer. The bottom one on the turbo muffler in front of the motor.
The drilling in the block goes about twice as far as the bolt actually reaches.
It's another inverse Torx, I think is E6 size. The length from memory is 3 1/2" but because of the standoff length, it only goes into the block a squirt more than 1/4".

It's very easy to over torque and I bet there a a bunch of them which have the block threads stripped.
I had bought the cb-engineering aluminum replacement, so I countersunk where the bolt goes through to get a much better purchase.
I called my local dealership to see about getting a longer bolt, but they didn't list one.
And, the stock Bakelite piece, you can't really countersink it.

(edit)
All this is regarding the CDI version of the 642.
I wonder if that bolt is sufficient on the newer style muffler?

 

@rmassmann great seeing the progress as you are finishing this up. I can relate as I did this last year and brings back memories. Seems like a daunting task until you get into it. Don't forget to check your oil level and remember to refill the coolant if you drained it and keep an eye on it as you restart as you will need to top up. Speaking of restarting, don't be discouraged when you try to start and it doesn't right away. I think it took about 4-5 times trying to restart before it started, ran a bit rough initially but then smooths out after.

Good luck and hope you get it all finished soon.

 

I have been working to complete the engine oil seal leak repair for many weeks now. I started in mid-February. After finally getting the fuel injector return line yesterday, I was able to finish putting sound damping, turbo inlet plenum, and engine filters back on the car. The passenger side filter is a real bear to get in place and took me several tries. Refiled to coolant and then cranked the engine many times before it started. But it is running now and will be taking out on a test ride later today. Hopefully I will not have to do this repair again?

Wish me luck down the road?


Most everything is mounted, Tada!

 

Congrats and really well documented. I hope everything went well.

When I had finished mine, I washed out the engine bay after and removed the lower splash guard to clean it out. Then drove a few days without the splash guard and put a cardboard underneath where the vehicle parked. After a week with no leaks or any other issues noticed I replaced the splash guard underneath and sighed with relief.

 

Mikey178,
Thank you for the note. I had removed all the shielding before I started the job. Center panel was an oily mess and it need to drain. I had one fuel leak, luckily at the fuel filter. Found it after a drive around the block. I haven't had any other leak signs and did a short run trip to the store of about 24 miles yesturday. Yes, there is a bit of hesitation and apprehension driving the car and worrying that I may missed something or did something wrong? Hopefully I will get to enjoy it for many more miles. I believe this is the nicest car I have ever owned, having only bought (3) new cars since I started driving, Volore station wagon, VW Rabbit diesel and Honda Accord. I will be working on the parts list, vender list, and price over the next couple of days to post to the forum.
Take care, BM

 

Looking forward to seeing that information. It ill be really valuable for all of us looking to undertake this job in the future.

 

Please see the attach document with final expenses for my oil cooler repair. It also includes part numbers and cost for extra part that were not included with the basic oil cooler repair kit. I have taken my ML on one long drive since the repair with no issues, was very pleased with the cruising MPG of 33.5. Hope the part numbers help

 

This is great, thank you very much for shairng this.

 

I've just done had mine done, search around for the best price, in Australia the common price was $230+ but I found one on eBay for $75 delivered. Brand new and is identical to original including parts number. Took just over 30 minutes to replace and the old one was filthy.

 

I was astounded at the amount of soot that had accumulated down stream of were the EGR gas is introduced into the manifold supplies as well as intake charge manifolds. I removed almost a pound of soot from that part of the engine. This car only has 88K miles. My next task is to replace the broken rear suspension springs. I am going to replace with Bilstein spring and hopefully avoid broken spring issues. Left and right are both broken, and are broken near the bottom of the coil.