The pistons are not actually pitted, there is just carbon deposits on them. As for the scratch, when you run your finger across it you cannot feel it. Only when you run your fingernail across it can you feel a very slight imperfection.

The engine ran fine until the chain broke, it happened all of a sudden. Only thing to note is that under load and high rpm there was a noise coming from the front of the vehicle. I could not replicate it under normal conditions and whether it has any correlation to the chain breaking I don't know. I tried to dianose the noise but I could not narrow it down. It could have been anything, my a/c pump is seized, my alternator pulley makes noise, or just normal diesel noise, I don't know.

My tower are intact. The arms and camshaft lobes have very bad wear and scoring on them. The only thing that actually broke was the chain.

I will try to take pictures tomorrow, it is dark outside.

This is a personal decision.

If this where my vehicle........................................

#1. Replace the valve guides, regardless.
#2. Replace the cam shaft and towers.
#3. Install a new head gasket.
#4. Install a new timing chain.

Enjoy the car.

IMO: Going further may well run $3k - $7k, depending on parts / labor.
Unless you are prepared to do 100% of the work, and live without the vehicle a month or more.

.

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Good advice from all, so I will add nothing, except to ask, how many miles on the car when it happened and was it the original chain??

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2012 Mercedes ML350 Bluetec 102K (hers)
2005 Corvette 55K (fun car)
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1998 Volvo S70 T5 Turbo 211K (kids)
1994 Ford F150 4WD 246K (firewood hauler)
1983 Mercedes 300D 384K (diesel commuter)

The car had 232,385 miles on the original timing chain.

That was the plan, to go through the top end. New valves, valve guides, timing chain, timing chain tensioner, timing chain guides, full engine reseal kit, and do work on the cooling system while I am in there. All the work will be done by me on days off and evenings. The vehicle has already bee sitting for around three months and I expect it to sit another three at the pace I am going.

I thought about just fixing the head and then putting the engine back together but I just wanted to get some opinions from the mercedes gurus on the forum.

I do agree with this but at the same time I think that that is also a lot of money to spend on an OM616

Rough estimates for what I'd expect that to cost here in clog land =>

head gasket 80 euros - timing chain 80 euros (IWIS) - camshaft is about 100 euros (last time I looked) - should replace followers (about 25 euros each => 200 euros) - camshaft towers good second hand about 30 euros each => 150 euros (I think there are 5!) - valve guides are cheap but then valve seats need to be re-cut and then the valve should ideally be re-ground so a redone head is at least 300 euros here...

...that's the best part of a grand

Now I know clog land != US of A but you know even with a fair amount of smart shopping I can't imagine it is going to be much under $500

I'm not trying to be negative but - well - you know????

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1992 W201 190E 1.8 171,000 km - Daily driver
1981 W123 300D ~ 100,000 miles / 160,000 km - project car stripped to the bone
1965 Land Rover Series 2a Station Wagon CIS recovery therapy!
1961 Volvo PV544 Bare metal rat rod-ish thing

I'm here to chat about cars and to help others - I'm not here "to always be right" like an internet warrior



Don't leave that there - I'll take it to bits!

Have you inspected the vacuum pump yet? That is a common item that can break the timing chain when it fails.

IMO it is cheaper and less work to put in a good used engine.

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