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
Tell your mechanic once again to start the car before fitting the belts & then again after fitting them. You might still have a noisy pulley.
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Joined: Mar 2008
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From: 1 hours drive north of Sydney Australia
2007 W204 220CDI Classic Sedan
Light Dragon,
If the noise is not apparent with the Aux belt removed then it must be coming from one of the auxilliarys.
Taking a guess that it is the alternator may not be cost effective. The noise may be coming from any auxilliary.
With a noise as loud as you have any decent mechanic with a stethescope would be able to diagnose which item run by the aux belt the noise is coming from. It is simply a matter of going to each on numerous occasions for the noise comparison.
I would not be putting in a new alternator until I was sure that it is the offender. Tensioners cause a lot of problems & probably wear our first. followed by idler pulleys, air conditioning compressor & the belt itself.
Look after your back pocket & proceed step by step. The mechanic will only be too happy to try things at your expense. Sounds as if he needs to have a little gentle pressure applied or go to someone else.
If the noise is not apparent with the Aux belt removed then it must be coming from one of the auxilliarys.
Taking a guess that it is the alternator may not be cost effective. The noise may be coming from any auxilliary.
With a noise as loud as you have any decent mechanic with a stethescope would be able to diagnose which item run by the aux belt the noise is coming from. It is simply a matter of going to each on numerous occasions for the noise comparison.
I would not be putting in a new alternator until I was sure that it is the offender. Tensioners cause a lot of problems & probably wear our first. followed by idler pulleys, air conditioning compressor & the belt itself.
Look after your back pocket & proceed step by step. The mechanic will only be too happy to try things at your expense. Sounds as if he needs to have a little gentle pressure applied or go to someone else.
Thread Starter
Senior Member
Joined: Aug 2009
Posts: 290
Likes: 1
w203 M111 E20 ML EVO
Carsy friend, the noise goes away when removing the right aux belt. if the right aux belt is on and remove the left one the noise is still there. now, the right aux belt connects to the s/c the tensioner and the alternator. the s/c and the tensioner were both replaced with brand new and only the alternator remains to be replaced - guessing that's it, causing the problem. I so much wanna end this adventure tomorrow, pls pray for me as well hehe 
Last edited by LightDragon; Sep 18, 2011 at 06:54 AM.
Super Moderator
Joined: Jun 2008
Posts: 19,942
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
OK - you never told us you had replaced the belt tensioner which is why I suggested you take the good practice of starting the cars sans belts first.
Thread Starter
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Joined: Aug 2009
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w203 M111 E20 ML EVO
ok here's the deal.... afterr alllll this time. i bought a new c-class. i removed the larger crankshaft pulley+headers from the old one and installed them on the new and vice versa(the normal exhausts from the new transfered to the old one). THE NOISE FROM MY OLD C-CLASS HAS DISAPPEARD!! WTF!!! and i cant define if im hearing the strange noise on my new one or not, my mind messes with me... why has the strange noise disappeared from the old one new its back to normal ?????
Thread Starter
Senior Member
Joined: Aug 2009
Posts: 290
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w203 M111 E20 ML EVO
I finally figured it out... ITS A ****IN MANIFOLD LEAK! THEY ARE CRACKED SOMEWHERE AND THE SOUND I HEAR IS ESCAPED AIR! DAMN! I VE BEEN THROUGH ALL THIS PAIN AND EXPENSES WHILE THE SOLUTION WAS SO SIMPLE! ****IN MECHANICS THEY SUCK! Thank God i found out what happened and ended up with a better w203, the only thing left is sell my old one and Ill be right there I started
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Junior Member
Joined: Sep 2011
Posts: 63
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From: new jersey
06 c280
well my check engine light was on i forget the code but it turned out i had to chain my balance shaft. it was making a wierd sound then the check lightcame on so i would get it checked out cause it cost me 2500 to fix my balance shaft ill post up pics and show you how intense it is its about 22 hours of work
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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
Yes - this is a known problem on some M272 engines. They had sintered sprocket wheels on the balance shaft drive. Replaced with good old steel ones & all is now OK.
