Help Required! (CLK320)

[DayTrader]

Hi everyone - to start with I love driving and cars but have no idea what goes on under the skin!

I have inherited an X reg CLK320 and today it has started making a whining noise which gets louder as the revs build - I think it is coming from the thick rubber belt which is at the front of the engine...

Couple of questions:

Is this the cam belt? (I have no idea what it is called!?)
Is this a common problem?
Is it easy to fix / how much should I be looking to pay?

Cheers in advance, I will now hang my head in shame at my lack of knowledge!

Edit: Should add the car is from 2000 and has a naughty 150k under the belt!

[mbtech01]

Your vehicle does not have a cambelt - it has a timing chain which is maintainance free. The belt your talking about is as Mercedes describe it the 'poly v belt' which in simple terms is your fan belt.
Its hard to diagnose the noise/whine your on about without hearing & seeing the vehicle. It could be several things, a noisey alternator, worn power steering pump, faulty air conditioning compressor pulley - all these items are driven by the poly v belt & the first point of diagnosis would be to remove the belt, run the engine & see if the whine disappears. If it does then you've narrowed the problem down to one of listed components, alternator, pas pump, compressor or possibly idler pulleys or tensioner pulley.
If your not handy with the spanners & don't feel competent enough to remove the belt, then i'd recommend you take it to a Mercedes specialist or local trustworthy garage to have the problem diagnosed. It shouldn't take many minutes to make an accurate diagnosis.

[DayTrader]

Thanks for taking the time to answer - just what I wanted!