I've just bought a 98 c43 and it doesn't have the drive belt on. I'd appreciate it if someone could attach a belt diagram.

 

Here you go. The diagram is also for our C43 cars.

https://mbworld.org/forums/c32-amg-c...t-diagram.html

 

Now that you have the diagram (see above post from speed43), I would strongly recommend you check the wear on the pulleys before putting on a new serpentine belt. Usual culprit for excessive wear is the idler pulley #7 on the diagram and the #1 automatic belt tensioner. The idler pulley is cheap to replace, the belt tensioner a bit more. With the age of these vehicles, if these items have never been changed, it may be a good time and preventive maintenance to do so. While in there check also for possible wear on the water pump axle.

 

Thanks for pointing that out. I should have mention that too. Specially with what happened to me. I hit the gas pedal hard doing a test run and the belt came off the pulleys. It got shredded after it got loose. I had to remove all the bits and pieces around the water pump pulley. I thought I had it all but some tiny pieces had stayed behind the pump. This caused stress on the pump and 2 months later the water pump went bad.

Belt and water pump were replaced a few years back so they weren’t that old. So it’s far better to replace what Daniel said, well worth it.

 

These are the different sounds one may hear when parts are wearing out: water pump and belt tensioner. Sorry didn't record the idler pulley on the top though. After installing new parts, the engine became super quite which I guess ia always nice to hear.
I guess a short video says it all