Strange Noise: Timing Chain
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
17,14 & 26 & their sub assemblies all guide & tension the chain. The chain is tensioned both mechanically & hydraulically.
I doubt that the accident had anything to do with it unless the impact dislodged something that was loose already. They just sometimes fail. Sh-t happens.
I had a new W202 in 1998 with the pre Kompressor version of the M111 engine. The chain tensioners & the camshaft adjuster failed in the first 2000Km's of that cars life & became noisy. They replaced the chain & tensioners & did the Benz deburring exercise on the adjuster. All was quiet for 2 weeks & the cam adjuster started making a noise again so they replaced that too. That was the end of the problem & it never recurred.
On high mileage engines that have not been adequately maintained with proper oil change interval & correct approved oil the chain sprockets on the cams & crankshaft can become worn. Then even if you fit a new chain the sprockets wear the new chain until it starts slapping around & giving the tensioners a hard time. If that is the case then you need to replace the sprockets & the chain & tensioners.
You need to open up the cambox & chaincase & inspect everything properly after using an engine stethescope to ensure that that is where the noise is coming from.
Good luck!
I doubt that the accident had anything to do with it unless the impact dislodged something that was loose already. They just sometimes fail. Sh-t happens.
I had a new W202 in 1998 with the pre Kompressor version of the M111 engine. The chain tensioners & the camshaft adjuster failed in the first 2000Km's of that cars life & became noisy. They replaced the chain & tensioners & did the Benz deburring exercise on the adjuster. All was quiet for 2 weeks & the cam adjuster started making a noise again so they replaced that too. That was the end of the problem & it never recurred.
On high mileage engines that have not been adequately maintained with proper oil change interval & correct approved oil the chain sprockets on the cams & crankshaft can become worn. Then even if you fit a new chain the sprockets wear the new chain until it starts slapping around & giving the tensioners a hard time. If that is the case then you need to replace the sprockets & the chain & tensioners.
You need to open up the cambox & chaincase & inspect everything properly after using an engine stethescope to ensure that that is where the noise is coming from.
Good luck!
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Thread Starter
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w203 M111 E20 ML EVO
if it was the timing chain why wasnt the sound louder when I opened the oil cap ?
also there is no logical explanation for the issue to be the timing chain mechanism because when i disconnect the s/c the sound goes off by 80% which wouldnt make any sense
also there is no logical explanation for the issue to be the timing chain mechanism because when i disconnect the s/c the sound goes off by 80% which wouldnt make any sense
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From: 1 hours drive north of Sydney Australia
2007 W204 220CDI Classic Sedan
Have you borrowed or bought a stethescope yet?.
This site has many knowledgable participants but few have ESP (Extrasensory perception).
This site has many knowledgable participants but few have ESP (Extrasensory perception).
Super Moderator
Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Please try removing one spark plug coil at a time so that the engine does not fire on that cylinder & see of the noise reduces.
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w203 M111 E20 ML EVO
tomorrow I will try the following:
1. Check the Headers for leaks
2. Remove the sparks one by one
3. Replace the timing chain tensioner
If I try all of the above and the noise still goes one, Im selling the car
1. Check the Headers for leaks
2. Remove the sparks one by one
3. Replace the timing chain tensioner
If I try all of the above and the noise still goes one, Im selling the car
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Please replace the timing chain at the same time. Never fit a new tensioner to an old chain.
I have listened to you clip many times & it sounds mechanical & typical timing chain box noise.
However - in the area you think the noise is coming from the only thing I can think of is a piece of Cat honeycomb that has broken of & is rattling in the exhaust. It simply does not sound like headers.
Are you absolutely sure that the car is not storing any codes?
EDIT - & don't remove the spark plugs, just cut power to them one by one & listen to the noise change. We need full compression on all cylinders.
I have listened to you clip many times & it sounds mechanical & typical timing chain box noise.
However - in the area you think the noise is coming from the only thing I can think of is a piece of Cat honeycomb that has broken of & is rattling in the exhaust. It simply does not sound like headers.
Are you absolutely sure that the car is not storing any codes?
EDIT - & don't remove the spark plugs, just cut power to them one by one & listen to the noise change. We need full compression on all cylinders.
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From: 1 hours drive north of Sydney Australia
2007 W204 220CDI Classic Sedan
Thinking out of the square about your red circled location , I had a piston skirt part from the rest of the piston once in a 4.4 L Rover/Buick engine. The broken piece did not part from the piston as it was held by the jigsaw effect. The knocking noise became more pronounced as the wear increased.
Just a thought...a piston.
Just a thought...a piston.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Yes JC - Thats why I want him to unload cylinder by cylinder. It would show up small end bearing, piston etc. failure.
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w203 M111 E20 ML EVO
well, i checked the the headers and they are alright... all i can think of at the moment is a bad alternator as i removed the right belt today again and it was pretty much silent...
MBWorld Fanatic!
Joined: Mar 2008
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From: 1 hours drive north of Sydney Australia
2007 W204 220CDI Classic Sedan
Thread Starter
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Joined: Aug 2009
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w203 M111 E20 ML EVO
stethoscope sucks, wasnt able to locate nothing with it. I dont recognize the noise when using it. I bet its a bad alternator as the noise goes away after removing the right serpentine belt - as in different case( if it was coming from inside the chaincase ) it wouldnt go away.
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w203 M111 E20 ML EVO
I know Glyn but that stupid mechanic of mine told me he stills hears the noise after removal of the belts. when i told him to do it again he sais " oh i dont seem to hear it now" arrgghhh
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w203 M111 E20 ML EVO
thanks man. Monday its the BIG DAY! After replacing the alternator and put the car back together Ill stand by the ignition key... hold it in my hand, say my prayer and turn it slowly while my agony and tension hit red! The greatest moment.. a moment of silence as after starting the car Ill be either too happy or too sad...
