Just mark the cams for reference. You don't want to lock them in place as you are turning the whole rotating assembly while feeding the new chain.

 

Sak....here is what the dealer replaced on mine. Major items are timing chain, cam sprocket (not sure why only one?), tensioner and a bunch of seals and orings.

Hope this helps,

 

"Valve cover is the cam bearing halves so torque is crucial."

Yes, it's an interesting design that probably saves MB some money. Not sure if they have caused issues or not, so maybe smart engineering. I actually went out and got a new 1/4" torque wrench because the torque specs are pretty light. Had to convert N-M to In-Lb on all the instructions.

"Is there a special service tool that holds the cams when you have cover off?"

Yes, but I'm struggling to understand why it would be necessary. Once you verify that the timing marks are aligned, you split the chain then turn the crankshaft nut to rotate the new chain into place. If you have the cam locks in place, you sure aren't going to get far.

 

Krusty, thanks for posting this. Verifies my parts list. The copper seals and o-rings are for the injectors, those items are one-time use. If you read the Jeep forums (a lot of diesel Jeeps used this same engine until Fiat switched to an Italian one) the Jeep guys have had bad problems with the o-rings leaking and causing what has been termed "black death" which is solidified diesel fuel. You see it on the Sprinter forums too. So the procedure for changing them out is well documented. I ordered all of those as well after reading those posts. Finally, the 6 bolts are one-time use bolts that old the fuel rail in place. From what I can tell they are one-time use because they have loctite on them already; not sure why they don't just specify using loctite when you re-install. They are not high-torque but probably subject to vibration. The rest of the stuff is generally MB-specific gasket maker (loctite 5970 for the cam cover) and cleaners and greases for the injectors.

I've got all the tools and parts assembled, now just need to do the job when I can find a spare few hours.

 

i actually have seen a tech on a different repair "forget" there is a cam fixing tool installed and trying to turn the crank with a long breaker bar... nothing like a broken crank pulley bolt to spice your workday and turn a $2500 job to a $5000 one

 

As I mentioned earlier I had wanted to stay with a 5w40 oil. The Castrol edge oil that I have using, has been harder to get.

Anyone using or have knowledge of the motul 8100 extra clean. It is 229.51 rated.

Thank you.

 

Have you tackled this yet? I'm debating on doing this myself to save some cash. But I have a few more questions. I haven't purchased a manual to see the full procedure but from what I've found online it's not really complicated just time consuming. But I keep hearing that you need to pull the engine! Why from what I can tell looking at it the valve cover removal doesn't need the engine pulled and there is plenty of space between the radiator and the engine to get to the front end of the motor for the guides. I can see it on a E-Class but the GL seems to have plenty of room. The chain splitter looks to be a few hundred dollar tool but apart from that just normal tools that I already have. Am I missing something big here that makes it a bigger job than it looks?

 

I'm more than half way through it. Whether it's difficult or not depends on your mechanic skills, but it is undoubtedly time consuming. I've got the new chain in (you absolutely need two people for this part of the job, and don't think that your wife is going to do it, you need somebody that is good with a wrench) and working on riveting the new chain together. The WIS shows this being done with the factory tool with the right side intake camshaft installed, but the gear on the camshaft interferes with the tool, making it seemingly impossible. On top of that, the bolt to remove the sprocket on the cam is hidden under the cylinder head, so that can't be removed to rivet the chain with the cam out...not a great design.

I'll figure it out, just need to find the time to do it.

I've been working slowly and carefully, and started another thread (search: timing chain in the X164 forum) and at this point, I've probably got 20 hours into the job. If I were to do the job again, it would take 1/2 that, there is a steep learning curve, unfortunately. For instance, I wasted 2 hours just removing the valve cover. You are supposed to use the slide hammer to take it off, but that sucker is glued on and you have to use a ton of force to do it. Looking at what it would cost to replace it, your brain is not keen on applying that force. Plus, I had to fabricate an adapter to make my slide hammer fit...and I also removed the left valve cover to make sure I had the timing marks on both sides to work with - that alone was an extra 3 hours.

Anyway, look for my other thread. I'll write up a DIY when I'm finished. And no, you don't need to pull the engine.

And FYI, I can change engines on my BMW race car in 10 hours with no help, so the fact that this job has already taken double that has me in quite a foul mood.

 

Is the new chain thicker or has greater tensile strength than the old one ? Why is the damn chain stretching ?? tensioner pushing it too hard due to oil starvation ?

 

I don't think they have updated the chain in any way. But mine was stretched considerably. The new one went in *tight* because the old one felt very loose. I'm guessing 10-12mm over the length.

Anyway, I don't think anybody knows why. My guess is that lack of oil pressure to the tensioner results in insufficient pressure on the chain, which then moves around more than necessary and that extra movement results in the wear. Holding the chain in your hand you have a difficult time imagining it could stretch.

 

I have a 2012 with the same issues. I replaced the tensioner and it now rattles all the time, not just on startup. Is going to shop tomorrow to get chain replaced. Was reading all the post to see if there were any alternatives. SO FAR, I HAVE NOT FOUND ONE. I have 73k miles on my 2012

 

Hey man, do you think as a preemptive measure I should change the tensioner, from what it seems it goes bad and then pushes the chain way too far causing it to stretch.. does this make any sense ? Lol
I'm at 50.2k and so far no chain rattle, .... oil cooler is a different story though...

 

its good prevenative maintenance

 

I agree. I actually bought two tensioners when I did the timing chain job recently. I'll swap in a new one after about 25k miles. They're only $75, so no big deal if it helps prevent the chain stretching again. The timing chain replacement is not a job I want to repeat anytime soon.

 

2010 gl350 owner... I know this thread hasn’t had much activity but I’m just hoping one you nice guys can give some advice.
my gl has 135k and that knocking sound in starting has been around for about 80k... dealer service advisor said it’s normal. Ow it’s getting worse and sounds worse when in reverse or making turns. I’ve spent a lot of money on the air suspension, oil leak and was wondering is it worth repairing the timing chain or sell the car. I love the car but the repairs seem to be piling up. Worried something major is going to go wrong while driving....scared to drive very far with it. Was quoted by a certified Mercedes tech who has his own repair shop for 1900 to replace the timing chain. But from reading the thread it seems there’s going to be lot of other parts that need to be replaced. Any advice is greatly appreciated by this newbie....Thanks in advance......Geo

 

I did the timing chain job myself last winter. There are no other parts that you need to change along with it, except for some very small items (washers, etc.) I suppose, like any job, that there are some things that you could do "while you are in there" but really it's just the chain. $1900 is a pretty good price. It's essentially ALL labor, as the chain and tensioner are not terribly expensive and the rest is shop supplies.

 

Add my 2013 GL350 to the stretched timing chain list. 79k highway miles, serviced as scheduled at MB dealer, no towing. Replaced chain at 79k. Now 95k and hopeful it won't happen again.

 

How do you use your GL?

 

90% highway, no towing

 

At 75K I had the chain stretched -- I would love to know why? I suspect for some reason MB spec oil might be good for emissions and not so great for lubrication. Worthy of a read: http://www.stephensservice.com/bluet...ssuesproblems/

 

Nice, should be a must read for anyone wanting a diesel and any current owners.

 

my experience with the om642 motors is not aligning to what the guy wrote in that article.

 

Alx - have you seen differences in the Sprinters versus the SUVs? Seems the Sprinters have somewhat less problems with oil coolers? And I have seen Sprinters with over 500K miles on them.

The only thing I have done pertaining to the article is removing the engine cover. That did make a difference in engine temps while towing in AZ. (logged it).

 

My local dealer built a new service area that basically doubles their shop space just for the diesel MB's and Sprinters. It does not speak to their dependability. I don't know the guy who wrote the article but it echos what I heard from MB technicians and from what I've read over the years on the issues. What he is saying about the oil makes perfect sense.

 

i do see sprinters too. they do not appear to be more or less reliable. some of them are starting in the morning and stopped at night- so best case scenario. others though are delivery vans that see few dozen starts each day. what i do know for a fact is that i already saw 3 of them with more than million miles on the stock engine and transmission. i also have several 07 gl320s with more than 500k miles on stock engine/ tranny. i have yet to see any gassers with more than 300k miles. the several i have seen at about 250k were all on their death beds in terms of compression and top end wear. just data points.