1990 3.0l v6 belt routing mercedes 300 - 300-Class Mercedes-Benz Cars & Trucks

Go to the following link and the first photo shows the belt routing. I hope this helps as I know changing the belts on these vehicles can be a major pain in the neck.
Pelican Mercedes Benz Tech Article Mercedes Benz Drive Belt Replacement...

The ancillary belt routing diagram for a 1991 mercedes-Benz 300 TE

The ancillary serpentine belt routing diagram for a 1993 Mercedes-Benz 300

These can be real tempermental so I recomend and have done it this way professionally, pull up on the belt as hard as you can and pull towards you. Make note of the routing before you remove the belt as these can be tough to remember. I start at the power steering pump which is on the driver's side and pull. When you install the belt (in the same fashion) locate the writing on the belt and make sure that installed that you can read it like holding a book in your hand. If it is upside down you may get squeels and squeeks even on a new belt. The reason it is done this way even by Mercedes techs is because the tensioner that is used has a very thin adjuster rod in the back of the unit and usually breaks when turned. Once that breaks, you are looking at replacing the entire tensioner ($200 - $300). Not worth it!! Let me know if you need anything else.

if not painted over it will be on the radiator support when you open the hood or on the underside of the hood.

2001 MERCEDES-BENZ C320 - V6 3.2L 3199cc GAS FI N

Belt Routing Diagram Multiple Accessory


DAYCO Catalog

I hope help you with this (remember rated this help). Good luck.

Click on the link below, enter the year,make,model and engine of your car, then click on the Belt Diagram link to get a diagram for your serpentine belt. Best of luck!
Greg

http://www.mvreader.com/multiview/dayco/index.php?bgInterchange=1&l=n

This may be of some help.

It is a straight forward procedure, but getting it around the fan is tight. Just put a wrench on the belt tensioner pulley, and pull up on it to loosen the belt. While holding the tensioner up, slip the belt off. Just make sure you draw a diagram of the belt routing, before taking it off.

I know it's a little large, but here's the belt routing diagram you are looking for. Hope it helps!