OK, so my '04 E55 went in for service "F" the other day, and one of the things I asked them to check were the Belts.

They did check them, and said they needed replacing, due to the appearance of cracks etc. Over the 'phone cost for R&R was $299+tax.... so I thought better than that, and passed, deciding I could do it myself.

So here goes with the Serpentine Belt DIY... probably a 1/2 hour job all told.

I found a thread on the E-Class section (here) that gave a rough start to the idea. The E55 engine is a little different (at least on mine!) in that the tensioner is "upside down" in relation to the PDF in that thread (copy here for reference)

The belt part number is A113 997 02 92 and runs about $75+tax at the dealer.
[I also bought the new supercharger belt at the same time (A113 997 01 92 @ $32+tax]



Tools needed:
5mm dia drift (I used a small Allen key)
17MM 12pt socket (make it a deep one or put it on an extender!)
Extension tube (or use a longer handle ratchet) - I used some 1" conduit
a length of "stick" (to aid in gently pushing the belts into place)



Remove the top front cover and the two inlet tubes.
Pull up on the cover, and ease the tubes front off the inlet boxes (pulling towards you) , then back away from the front housing section by the radiator (push them towards the rear of the engine).



Then you need to remove the supercharger belt and there's a great thread here on how to do that...

https://mbworld.org/forums/w211-amg/239591-supercharger-belt-replacement.html

The first trick was in trying to determine how the tensioner worked. It's located just to the upper right of the main crank pulley, but the nut used to rotate it is kinda hidden below the belt (and there's not a great deal of room to get at it either). You'll see that it doesn't match the detail on the regular 211 tensioner PDF.. and I could not see a latching/locking pinhole like the supercharger one has.



So, place the socket and ratchet on the nut, and rotate Counter Clockwise (lefty loosey) about 60 degrees or so... note the clearance from the ratchet to the main crank pulley... that's why you need a deep (but not too deep) 17mm socket!!



Now slip the loose belt off the idler pulley to the upper left of the main crank pulley.



Now, ease the tension off the ratchet and let the tensioner pulley go back. You'll feel the limit being reached and I encountered no harm in letting it do so.
Remove the ratchet/socket off the idler pulley.
The belt now unravels off the ribbed pulleys etc, but you find getting it off the Power Steering pump pulley a little "tight" to say the least!!
The belt has very little room to slip through, between the pulley and one of the feed/return tubes.



Once it's removed, then start feeding the new belt back on in the reverse sequence.

I found the hardest part to be getting the belt back over the Power Steering pump... There is so little room to get hands in and manouver, but pushing the belt upward and at an angle (with the belt's ribs downmost) between the pipe/pulley worked pretty easily (eventually!).
I used the stick to assist with pushing the belt down and under the crank pulley, and then feeding the belt round everything except the idler pulley to the upper left of the crank pulley.

Put the socket back on the tensioner, rotate CCW (left) to ease the tension, and then slip the belt over the top of the idler.

IMPORTANT - Ensure that the belt is cleanly located/centered in the grooves of any of the pulleys it's fed over!!

Increase the tension on the tensioner by letting the ratchet/socket rotate clockwise, and then remove.

Quick visual check and replace the (new) supercharger belt and you're about done...



Start the engine and perform another visual (no probs for me!).
Turn engine off, replace the air tubes and cover.

Job done and $200 saved in the process.

 

thanks for sharing your write up...not too many of these floating around

 

Awesome work and write up!!

 

Thanks... just trying to add back to all the info you guys post...

 

nice writeup clive...
i now know who to call when i need my belt replaced...

 

Good Job! Great pics.

 

Fyi both of those belts are only $20.00 here http://www.mercedespartssuperstore.com/

take the a off the part # when searching.

 

Can we make this a "sticky?"

 

thank you,great write up.

 

very cool of you for doing this, thank you!

 

PLEASE HELP! I can't get to the 17mm socket on now because the the tension release fitting is somewhat behind the crank pulley so the socket wants to go on at angle because the crank pulley is in the way...???? 713-865-1748.

 

Great writeup

Hmmm are you sure the socket is behind the crank pulley? I've never seen that before. How did you get it behind the pulley in the first place? It is a bit difficult to get the socket on but with enough playing around you should be able to get to it. If you have to, just go form the bottom of the car, it may make it easier for you.

 

I just replaced mine last night. My friend has a lift, so I did the tensioner from below (as suggested in WIS for our vehicles). The "hardest" problem about this was figuring out how it fit back on. I had a diagram and picture but once you take the old one off and have all those fly wheels and cranks staring you at the face, you realize that if you don't get it back on correctly, you aren't going anywhere... The 17mm socket fits easily on the correct place and there is a spot for the drift to fit, but you cannot see this from above... It needs to be up in the air. And you can get the lower parts of the belt on very easily from below...

 

With a pulley upgrade it is very difficult to get to the tensioner bolt from the top as stated above. I go through the bottom with a box wrench,done in minutes.

 

How did you guys manage to get the new belt on? I had the tensioner as far back as it would go and can't slide the belt on, still. Not even close!

 

Do you have the right belt for your car? I did mine as well following this guide and had absolutely no problems getting the belt on... Or, are you routing it right?

 

I am routing it right... I hope they gave me the right belt! lol It's the same size as the old one, just a tiny bit smaller (being new and not stretched)

 

$51 here >> https://www.getmercedesparts.com/oem...des-parts.html

 

SC Belt removal and installation is a breeze. 30 seconds max.

Serpentine Drive Belt installation is extremely difficult. Takes over 2 hours. Not 20 minutes. You can't even get your hand in there. You have to use a long wooden paint stick to get it on the pulleys. New belt is tighter, You have to slip it over the Coolant Pump Pulley last because this pulley does not have a lip and it is the most accessible. Take my advice: Just write a check and have it done.

 

I just did this in a parking lot after loosing the belt in the mountains.

I had a 17mm wrench and that is it! Route the new belt through all the accesories EXCEPT the water pump. Once the belt is properly secure grab the center of the belt (right by the WP) and pull up firmly over the water pump pulley. I did this with one 17mm open end wrench. It took me 45 minutes to install. It took medium force to lift the tensioner with the belt.

A good tip for those who can't access the tensioner bolt with a 180 pulley installed or have no tools...

 

Just did this today. I also highly suggest leaving the water pump last while reinstalling. It will save you a few hours and some swearing.

 

Makes it a lot easier if you pull the fan shroud

 

Pulling the fan shroud is harder than changing the belt?

 

its pretty much impossible to get arms and hands where they need to be unless you have a supermodel helper that has skeleton arms and squirrel hands

anytime i do belts, alternator, waterpump etc on front of car I pull the fan shroud assembly as makes life much easier and keeps your arms and hands from being cheese grated.... fan shroud is easy to get out too

 

You don't have the right tools, then.

I would like to know if I did something wrong when I pulled the fan shroud when I did my alternator. That thing was a ***** and a half to get out, mostly becuase I couldn't disconnect my upper radiator hose on the left.