pulley noise

[ggc]

I have just bought my very first mercedes. It is a 1997 C240 elegance auto.
The car itself seems to be in excellent condition but about three weeks into my ownership a noise has appeared. It sounds like a loud clicking or rattle coming from one of the pulleys and it only happens when the engine is at normal temp. Also it it much more noticeable when the engine is idling in gear. A slight touch of the throttle and it disappears.
It is difficult to pinpoint the source but one of the pulleys appears to vibrate in sync with the noise (this is a small pulley with a star shaped nut on it to the right of the cam and diagonally down from it)
I don't know what this pulley is for and I have never seen a car with so many pulleys on one belt before.
Does anyone have any ideas what this pulley does and/or if it could be the cause of the rattle?
Thanks

 

[television]

It should be just the idler ass; that needs replacement, lots of info here if you do a search.

Malcolm

 

[ggc]

Thanks, will look it up

 

[cobra427]

hi

I get the same on my C200 '99. Its the idler... I just drop a load of oil down the front and back of the thing and it goes quiet...

I do it once a year on av.. I went through a flood the other day and had water at one point running up the front of the bonnet!!!! next day squealy bearing noice fom the front - a few drops of oil and its gone again.. :O)

 

[42847]

noisy w202

my 2000w redg c200 had a similar noise at 70000m and 142000m it was a pulley wheel and engine shock absorber it could be same thing if you pm me i can give you part numbers required

 

[kth286]

cobra427

Do not drive through floods that deep.

If water got into your engine and caused a hydraulic lock you would now be looking at a bill for £1000's for a replacement engine.

 

[television]

cobra427

Do not drive through floods that deep.

If water got into your engine and caused a hydraulic lock you would now be looking at a bill for £1000's for a replacement engine.

Too true, and with all of the low Electrics around and modules, turn around and go the other way.

Malcolm

 

[ggc]

Sorry 42847 I'm new to this type of thing. How do I pm you?
Tried sending email but didn't work

 

[42847]

forget private message just ask me on this system

 

[anyweb]

hi

I get the same on my C200 '99. Its the idler... I just drop a load of oil down the front and back of the thing and it goes quiet...

I do it once a year on av.. I went through a flood the other day and had water at one point running up the front of the bonnet!!!! next day squealy bearing noice fom the front - a few drops of oil and its gone again.. :O)

anyone got a photo of this idler ?

i'd like to check mine out, could explain the same noise in my engine

 

[C220GJS]

Anyweb, There isn't an idler pulley on your engine, I expect cobra427 is talking about the tensioner pulley which does tend to screech as the bearings wear,and yes a few drops of oil to the pulley shaft front and back can quieten it for a while but the pulley will need to be replaced soon.http://www.detali.ru/cat/oem_mb2.as...GM=717.417&CT=M&cat=19K&SID=20&SGR=045&SGN=03
Geo.

 

[anyweb]

thanks c220gjs,

is it part number 26 in that pic that i should oil ?

 

[C220GJS]

Anyweb, part 26 is just a plastic cover for the nut,part 20 is the pulley and you can try oiling it front and back where the shaft passes through it to cure the screeching .
Really it's best to slip the belt off and spin the pulley to feel for roughness and play in the bearings, if it's rough or there is noticeable play you should replace the pulley.
Geo.

 

[anyweb]

thanks Geo good advice as always

cheers

anyweb