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Just acquired an E250 2013 with the OM651 engine - currently at 80k miles.
On a cold start, engine's a little noisier for a few seconds with a metallic rattle then returns to a nice idle (recordings attached for both cold start and idling afterwards).
Can anyone advised if this sounds like it's time for a new timing chain etc?
Some garages are advising it does - others are saying it's normal and just the hydraulic lifters/tappets due to it being parked for a few days and oil draining down into the sump. Apparently these engines should go past 100k before chain needs thinking about?
Would appreciate opinions to check whether it's actually a job needing doing!
Last edited by DriftR1DR; Mar 21, 2020 at 09:27 AM.
Some things to consider: Rattling noises from the front of the engine on the left, in the area of the turbocharger after cold start could be caused by vibration of aluminum bypass valve inside air duct housing, replace housing currently fitted with plastic valve (part # 6510901407 has not changed) and/or chain tensioner seal could negatively influence the pre-tensioning force this might lead to loosening of the tensioner, worst case oil leakage present.
I have 3 of those engines in my vehicles between 139k and 260k miles in Sprinter, where it works much harder.
You should love the 800 miles range on the tank.
Coming to the noise, I don't hear anything alarming on your file, but noise is pretty hard to diagnose over the internet.
Statistically chain tensioners are weaker item on those cars, so per konigstiger's links, you might want to replace it preemptively and see if that will make difference.
I've just taken a 30 second clip (please see attached) from the passenger side and it doesn't feel like timing chain here.
I've noticed the rattle is coming from the front right side of the engine (if you're sitting in the driver seat).
@konigstiger - when you said front left - did you mean looking at the front of the car or from the driver side as I suspect it may be this aluminium bypass valve now!
Few seconds of noise is typical for tensioner who lose oil in it. They operate using engine oil pressure to extend.
Good luck tracing source of noise on the engine. It is never easy job.
Did you ever find out the cause of this sound? Having the same sound on my OM651 W204 C250 CDI. A very slight rattle that lasts for about 1 second or 2 sometimes (attached). Any advice would be appreciated
Did you ever find out the cause of this sound? Having the same sound on my OM651 W204 C250 CDI. A very slight rattle that lasts for about 1 second or 2 sometimes (attached). Any advice would be appreciated
Hi, it sounds like the air duct issue check this link out
I have the same rattle for a 10-15 sec after a cold start then it goes away. It comes from the front left area where turbochargers and all the related plumbing reside. The timing chain rattle has been ruled out.
Here are a few videos that show where the bypass valve is located and a possible fix. Not a fan of a teflon ring as it will eventually disintegrate but to each its own. New air duct housing with a bypass valve is anywhere from $400-800 depending on a dealership markup that day lol
Czy kiedykolwiek odkryłeś przyczynę tego dźwięku? Mam ten sam dźwięk na moim OM651 W204 C250 CDI. Bardzo lekka grzechotka, która czasami trwa około 1 sekundy lub 2 (w załączeniu). Każda rada będzie mile widziana
It's a pity that so late, the sound is the pressure valve at the turbine, I've had it for 2 years, you don't have to worry. You can do it and 100,000 miles, the only problem is the annoying sound.
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E250 OM651 Cold Start
