Timing chain?
Thread Starter
Newbie
Joined: Jul 2025
Posts: 3
Likes: 1
2012 C180
Timing chain?
Hi!
Bought a 2012 C180 with 129.000 km 3 months ago. Now done 136.000.
Ever since I bought it I have noticed a rattle on startups. It’s worse when the engine is warm, quite a bit worse. On cold starts it’s still sometimes noticeable but definitely less common. I’ve attached a link at the bottom of the text to a video of me starting the engine on a hot summer day after driving for 2 hours. I checked for codes and the car shows none what so ever.
So the question is, what exactly is the problem? Timing chain? Camshaft adjusters? Both? How many hours of labor are we talking for a local mechanic with little experience in changing timing chains.
When doing the chain, is it enough to change chain alone or will that be just a waste of time?
To be honest, Im thinking of changing to a w212 in 6-9 months or so. Anyone reckon if the engine will hold until then or is this urgent?
Any help would be appreciated greatly!
Link
https://youtube.com/shorts/rCbMM3ngLlc?si=JkxMpGjcVcNCOVT-
Bought a 2012 C180 with 129.000 km 3 months ago. Now done 136.000.
Ever since I bought it I have noticed a rattle on startups. It’s worse when the engine is warm, quite a bit worse. On cold starts it’s still sometimes noticeable but definitely less common. I’ve attached a link at the bottom of the text to a video of me starting the engine on a hot summer day after driving for 2 hours. I checked for codes and the car shows none what so ever.
So the question is, what exactly is the problem? Timing chain? Camshaft adjusters? Both? How many hours of labor are we talking for a local mechanic with little experience in changing timing chains.
When doing the chain, is it enough to change chain alone or will that be just a waste of time?
To be honest, Im thinking of changing to a w212 in 6-9 months or so. Anyone reckon if the engine will hold until then or is this urgent?
Any help would be appreciated greatly!
Link
https://youtube.com/shorts/rCbMM3ngLlc?si=JkxMpGjcVcNCOVT-
Super Member
Joined: Jun 2017
Posts: 608
Likes: 107
From: Western NC
2009 MB C300 Sport 4matic
Cold start vs hot rattle would point more towards the tensioner failing over a slack chain per us "shade tree' mechanic's take. A change out would just as well include the chain albeit easier/cheaper to just change tensioner plus no need for chain breaker/riveter tool. If you are going to trade her in a failing tensioner might make it for quite a while if you don't push the RPM's, drive like a "senior" ! You could also in the meantime try a little BMW 5W-60 syn. oil drain/refill and see if the warm rattling gets better..the stuff is a bit hard to find and pricey. Or some Rotella 10W-50 might do the trick.
In summary, timing chain noise more noticeable at startup, idle classically. If you get a P0016 or P0017 code in the future that would suggest the chain has slipped a tooth.
In summary, timing chain noise more noticeable at startup, idle classically. If you get a P0016 or P0017 code in the future that would suggest the chain has slipped a tooth.
MBWorld Fanatic!
Joined: Sep 2013
Posts: 2,377
Likes: 703
2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
While at 136,000 km you could have camshaft adjuster failure, the noise in you video is no where near as bad as what that failure produces. Failed adjusters also throw codes, so lacking them is a good sign. A “stretched” chain or a bad tensioner seems like the most likely culprit. It is not uncommon for M271 engines to need chain replacements around 160,000 km. If the noise does not get better with higher viscosity oils, replacing the chain and tensioner may be in your future. A chain jumping a cog on M271 could be fatal to the engine because of valve/piston interference.
