Ok i've found the strange noise i was hearing form the front of the car it seems to be the tension pully for the belt it seems to have a bit of play and is moving around, so my question is can it be replaced if so what is involved.

There are lots of pulleys and accessories that can make noise.

If you release the tension on the spring and then remove the belt, you can run the cold engine for 30 seconds. If the sound is gone when you do that you've confirmed it is a related device. At that point, spin each pulley by hand to try to locate which device has drag and go from there.

If the sound remains with the belt off you have anohter issue.

Assuming your E200 is a W210 body, the tensioner pivot arm is removed using a 17mm hex. The easy way to get to it is to remove the radiator and fan.

The tensioner damper shock sometimes develops a bad bushing which can create a rattle, about half the time it can be removed w/o removing the pivot arm.

The tensioner roller pulley has sealed bearings which go bad occasionally, it is not too difficult to replace.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Thanks TM I'll check all the pully's tomorrow to be sure i'm right and it is in fact the tensioning pully thats gone. one question for ya is you mentsion a 17 mm Hex Where is that as i can only find a 10 mm on the damper and a 8mm on the pully wheel it self. By the way its a 99 E200 and i've no idea what body type it is as its my first merc.

It is indeed a W210 body (E-class).

The 17mm hex is used to remove the tensioner pivot arm that the shock, spring and roller pulley are attached to. It should have a black plasctic cap covering the hex head just like the roller pulley did.

If you put your car and your location into your signature (User CP) it helps everyone here help you. For example, E200 was never available here so will be difficult for you to get engine specific help, but knowing it is a 99 E200 W210 helps as many items (e.g.: tensioners) were used on more than one engine.

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Thanks for the advice TM i took the belt of and ran the engine for about 30 sec and the noise was still there so that ruels out all the pullys.
Again thanks for the Advice

For fun check your left motor mount to see if it is collapsing.

Should measure 13-17mm from the top rubber rim down to the next lower rubber rim. Use a 13 or 17mm bolt head to measure with. You can also lift the engine 1/4" (no more) and then look at the top of the mount from above with a bright light. If any cracks are present they need to be replaced.

I searched for a bad tensioner component on mine for months before figuring out I had a partially collapased mount which manifested itself at the tensioner.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)