Borrowed time?! ⌚ ☠

[clk320x]

I thought the timing chains never need replaced one of the reasons I kept my old w203 cdi. It's on 260k but I suspect it was clocked back so could be closer to 300k . No issues with the timing chain... I am looking to replace it with a w211 which I think are better build than the w212

No they are supposed to last the life of the engine unless they fail prematurely for whatever reason.

My 250 is now on 174k and my 320 on 265k and I have had zero timing chain issues.

 

[horatio]

I thought the timing chains never need replaced one of the reasons I kept my old w203 cdi. It's on 260k but I suspect it was clocked back so could be closer to 300k .

The old Om611/646 engines have a duplex chain at the front of the engine which should be indestructible if it's looked after.

I believe the 651 has a single row chain tucked away at the rear of the engine...

 

[Tonygw]

Mine started to rattle at 90K and mine is a c250 cdi OM651 engine 2012 model. I think its rare for this to happen. Mine has a good service history.
You WILL know when it starts to make the noise. Its a distintive clack clack noise for 2-5 seconds when starting from cold and as it gets worse you will hear it on some hot starts. Mine got progressively worse over a 3 month period but the car drove spot on. If your unsure go onto you tube there are plenty of videos showing the noise.

I got mine changed and all is quiet now. Mine had stretched at a couple of points along the change which made it somewhat intermittent as to if the noise would occur or not.

If you dont hear the noise then dont worry. And if you do, imminent failure isnt going to happen you have time. And the good news is its not a mega expensive job. (hundres not thousands!)

From reading a lot about this, its not a major issue and if you dont hear anything drive smug... if you do, then time to get it replaced.

But dont fret about it.. just enjoy...and keep an ear out now and then for any clack clack noises at start up.

 

[Monkeylegend]

Just over 311k on mine and the previous two went the same and no timing chain issues with any of them, so relax and enjoy.

 

[andym2]

You can use an oscilloscope to check the timing difference between the camshaft and crank sensors, which can show if the chain has stretched. Basically you get the waveforms from each and measure the phase shift between them. If the timing chain stretches then the cam will lag behind the crank.