tjts1

MB approved oil is for gasoline engines, not diesels hence the timing chain stretch.
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Getting the chain guides installed is a project. You have to pull the front timing cover which requires pulling the oil pan which requires pulling the engine from the car. If your car has a removable subframe you might be able to do it in the car. It's a massive project regardless. You could go in through the oil cap with a boroscope to inspect the guides. My guides still looked new at 220k miles but I replaced them anyway because I was doing a complete rebuild.

TxRzrBk

By MB oil, I mean oil approved for this specific vehicle...this ain't my first rodeo

alive19

I'm not sure if you have to drop the pan to get the timing chain cover off. You do have to remove both cam covers though. So It's a big job (twice as big at least).

tjts1

This row of screws attaches the upper oil pan to the front timing cover. You can only access these screws by dropping the lower oil pan and pickup tube. When reinstalling the front timing cover it needs to go back on the engine BEFORE the upper oil pan. So one way or another upper oil pan is coming off if you want to do the chain guides.


Also the upper oil pan cant come off without the rear crank seal coming off first. The rear crank seal bolts onto the block and upper roil pan. That means engine needs to be separated from the trans. The bottom 3 bolts around the seal attach to the timing cover.



I suggest just inspecting the chain guides with a boroscope camera and replace the chain through the passenger side valve cover. Oddly enough in this engine the plastic chain guides tend outlive the chain.

Yes I know, 229.51 and 229.52 oil that lacks an API CK-4 diesel oil rating because it's engineered for gasoline engines not diesels. These oils don't contain soot dispersant chemicals common to diesel oils so the soot ends up working as an abrasive in the timing chain elongating the holes where each link pivots. This is the reason your timing chain stretched despite your short oil change intervals. The metal in each link didn't stretch, the holes in the links expanded. Keep using 229.51 or 229.52 oil and you'll be replacing the chain yet again.

Good luck

John CC

OK, now I'm completely confused. The point of the dispersants is to keep the soot in suspension in the oil. Doesn't it then stand to reason the soot would be more efficiently carried to the chain (and everywhere else) where it could more easily do its dirty work?

So, what are the tradeoffs between using the CK-4/MB228.51 oils, the MB229.51 oils and the MB229.52 oils? (Besides the 3% decrease in fuel consumption.)

tjts1

Dispersants in diesel oil prevent the soot from clumping together and turning into sludge. It also binds to the surface of the soot so it can't stick to metal surfaces in the engine where it can do damage.

All I can tell from the data Mercedes provided is that 229.51 oil is recommended for a bunch of gasoline engines and 228.51 oil isn't. I've never seen an 229.51 or 229.52 oil bottle that also carries an API CK-4 diesel rating. If someone finds one please correct me. I have seen SN gasoline rating and 229.51 on M1 5w30 ESP. Every 228.51 oil I've seen also has the CK-4 or the older CJ-4 diesel rating somewhere on the bottle.


I think most of the fuel economy claim comes from the use of low viscosity oil, not the additives. There are similarly low viscosity CK-4 oils with the appropriate diesel additives if that's what you're after. The whole goal of recommending these low SAPS gasoline oils for use in diesel engines was to protect the DPF from clogging up with ash before the emissions system warranty runs out. If that comes at the expense of your timing chain, well that's your problem not Mercedes'.

kajtek1

tjts do you have any lab tests to support all those theories?

tjts1

I asked mercedes to release any lab tests they used to come up with the 223.2 sheet but they didn't respond. You should ask them too, maybe you'll have better luck. I'm glad to see you're as skeptical of their theories as I am.

kajtek1

What makes me different from you is that I put money where my mouth it and pay for lab tests.
Never had any oil-related engine problem on about 20 MB i bought for me and my family members and I follow FSS or Assist recommendations to full extend, even exceeding them occasionally.
Bare in mind, FSS originally was programmed for using dino oils and my 1998 ML320 was running 13k intervals on dino oils just fine, before lawyers forced MB to change the recommendations.

John CC

Actually, a least for my OM651, I'm pretty sure the timing chain is covered by the extended warranty.
(Confirmed:
The emission control system warranty shall cover the following parts or systems:
...
• Engine timing chain,
...)

tjts1

That's great news for your 651. Perhaps TxRzrBk can get his timing chain replaced under warranty. I'm guessing MB will find an excuse to deny the warranty claim but it's worth a try.
That 229.51/229.52 gasoline oil really f***ed him over.

John CC

I'm sure that's the only possible cause for his problems.

Not like any rod bearing I've ever seen... (or heard).

tjts1

If you've got a different idea I'm sure TxRzrBk is all ears. Or are you suggesting he keep doing the same thing and expect different results? Timing chain replacement every 20k miles on 229.51 gasoline oil sounds delightful.

alive19

Respect to your knowledge. The photos of the oil sump are awesome illustration of being correct in what you say.

Something would have to be stuffed in the engine to wear a chain in 20k miles. My original chain had 200k kms and doubt it had anything apart form the standard oil. Assuming the oil isn't contaminated and watered down with diesel or gelling with biodiesel, the chain should still be ok. If the tensioner is not extending, then either the chain is not stretched, or the tensioner is broken. It doesn't seem plausible both the tensioner and the chain would both fail after such a short time. I had a look at my tensioner, it is only extended about 5-10mm, about 1/3 what it used to be before the chain replacement.

Go through all the injectors. Make sure there are no fuel leaks on the high pressure side, nor any leaks through the brass washer on gas side. Injectors tend to tick louder when they have issues.

Check your accessory belt and pulleys. Don't think ticking would come from that but it's something that you would have touched to do the chain.

Then I guess you could start to put a screw driver on different parts to see whether it gets louder somewhere. HP fuel pump, AC compressor, heatsheilds?

John CC

1) there doesn't seem to be a rash of timing chains failing at 20K miles.2) just because he used 229.51 oil and had a timing chain failure doesn't prove cause and effect. Maybe it's the brand of cigarettes he smokes.
3) I have 80+k miles on the original chain. Carfax indicates regular dealer servicing for the first 70k. Does that prove anything?
4) if the chain is wearing abnormally, wouldn't that show up as metal in the oil analysis?
5) we don't actually know for sure his current problem is the chain, or if it is somehow related to something that happened during the previous replacement.

It would be really helpfull if you could explain the reasoning behind the recommendation of 229.31, 229.51 and 229.52 over 228.51. That way we could make our own decisions rather than relying on non-scientific statements like "That 229.51/229.52 gasoline oil really f***ed him over.".

tjts1

If you're going to use 229.51 gasoline oil in your om642 diesel engine, stock up on zip ties. You're going to need them.

John CC

Are you old enough to know what "you sound like a broken record" means?

kajtek1

Some idioms still last for generations and are repeated when nobody remembers where they come from.
My favorite is

'Don't throw the baby out with the bathwater'

care to find explanation without google?

TxRzrBk

I got the new tensioner today and installed it. Mind you I already removed and checked the existing tensioner and did not find anything wrong with it. When I removed the tensioner previously I pumped all of the oil out of it so that I would have less hassle getting it to thread straight.
Today when I removed the tensioner for the second time there was a very small chunk of what looked like casting sand lodged in the oil inlet. I tried to remove the debris with a small pick and it fell back into the tensioner so I'm still unsure what it is.
I checked the two oil ports on the motor side and found them to be clear.
After installing the new tensioner the chain slap at startup is gone and the motor sounds normal.
I think I dodged a bullet on this one however time will tell if there is any lasting damage.

alive19

Touché. I'm glad someone else had a problem getting it back in. I put in a new tensioner (old one looked fine, but I'd already bought a new one) and was shocked now much force was needed to compress the tensioner before the threads engaged. At one stage I even thought i'd cross threaded it. I'd forgotten that little nightmare.

Glad it was a simple fix. Well done picking up the noise and doing something about it.

TxRzrBk

Edit- the INA chain does not have oil holes...it also came with moly "break-in" lubricant
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There is a top and a bottom of the timing chain, the oil holes between the teeth need to be facing up. I did not think it would be possible to install the chain upside down until I saw a video of a guy installing the chain that way...I am still not sure how he did it.

As an aside, I am about to replace my chain for the second time due to a clogged tensioner that stretched the chain yet again.

TxRzrBk

I ordered an INA timing chain and it came riveted together, when I replaced my chain before I used a febi chain and it did not come riveted.
Did anyone else have to deal with this?

tjts1

Yeah, what's the problem?

TxRzrBk

Do you reuse the pins? It didn't come with new pins.

John CC

I thought you said it was already riveted together. Or, do you intend to break it and feed it in then reconnect it?