There's not enough room for me to work in there. Looks like I have to take out the fan...

 

Rubbish loads of room just like a 350

 

Very timely video, I'm been contemplating replacing my v belt..
Thanks

 

Update: Replaced the serpentine belt (the skin on my arms is a little worse for wear, I'm afraid - even though I used towels over the fan shroud). Checked all the pulleys. Everything is solid/no movement. However, the water pump whines when spun by hand. That's an expensive R&R, I'm told... Regardless, success! Thanks, everyone, for your expert judgment!

 

I'm thinking about doing this on my 350 this week. Is there a recommended brand of belt to get? And should the tensioner be replaced as a matter of course?

 

If i was you i will also drain the coolant and replece it.
Start with jacking up the car or put the car on ramps
Remove under tray
Connect a hose to radiator drain port and unscrew the screw
Disconnect the radiator electric plug
Remove the hose from thermostat and radiator
Remove electrical fan from radiator it has 2 latches on both side's and just pull it up
Now you have full acces to the belt tensioner, use a 17 or 19 mm socket with a long handle and a nail or a hex to lock the tensioner,
Now you can remove the belt and inspect the pulleys
There are 2 sizes belts be careful
Also now you can change the thermostat and thermostat gasket if you want.
Putting back the belt you start with the crank pulley
Imgur: The most awesome images on the Internet

 

belt should be mb brand in my opinion
and yes, replace any parts like the tensioner and pulley while you are in there

 

Thanks for the info. All sounds reasonably straight forward

 

Did this job today, no problems at all. The belt was the original from 2005 and 80,000 miles so no wonder it was squeaking.
I also changed the tensioner and the 2 idle pulleys, all of which were noisy.
Used genuine Mercedes parts so a bit more expensive but I thought it better to be safe than sorry.
What a difference, the engine is now so quiet.

 

Thanks, Avel

Your advice is well taken ! Vlad

 

Update: Had to replace belt, again!

After driving up to Virginia (a wonderful drive up through NC & VA, AND five laps @ VIR!!!), I was waiting at a light near my home & all the warning lights came on & my steering got real hard. "That damn serpentine belt, again! Good thing it happened here!". Pulled into an auto parts store lot, got towed to a local shop. They replaced the belt, and the Idler Pulley - which broke! - and I was back home in less than 1-1/2 hrs from alert! Double-checked my installation to make sure the belt was on correctly. Either it wasn't, or it was time for that pulley to go!:grin:

 

Hi to all just a few updates on replacing serpentine belt on 2005 (uk spec)slk200.
To release the tensioning pulley you require a male torx T60 socket which locates just below the tensioning pulley , you have to feel for it. Insert socket into cut-out and turn Anti- clockwise. The belt will slacken but you will have to keep the tension on the ratchet as there is no locking pin. Once released you can relieve the tension
Route the belt and when you are ready to place the belt over the final pulley tension pulley again and slip belt over whichever is your last loop . I would not recommend the tensioning pulley as your last loop as the ratchet gets in the way
Hope this helps
Marauder

Helpful hint from @marauder1964

 

If you take the fan out you can do the job easily in 1/2 hour. Just take note of how you take the belt off and you should not have a problem. I had to replace my alternator and they say you need to undo power steering tubes and a hole pile of stuff, The belt was about the only thing I had to do aside from the fan and even that you can do with next to no tools. Don't sweat it mate you'll do fine.

 

re: "new" SLK320: I'd replace all fluids & rubber components easily reached (belts hoses, tires) and put latteritems in baggies for the next owner. I'd also add Bluetooth. Check all sway bar and suspension bushings then check everything out, HVAC operation particularly. I like sheepskin seat covers.

Some things do not do well in storage, even climate controlled.

 

The procedure is documented already

Drive belt (serpentine) replacement

www.slkworld.com

I am here to convince anyone contemplating a belt replacement - don't be afraid of removing the fan. If you have the skill to replace the belt, the fan is easy. Having room to work makes this easy. I suspect the total time will be a wash because you can work so much more quickly with the fan out.