Jun 10, 2015, 01:02 PM
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How do I replace my serpentine belt?
Member
Joined: Dec 2012
Posts: 216
Likes: 1
2004 CLK 500 with AMG Package, Not Convertible
Refer to this:
http://benzbits.com/M112/BeltRouting.pdf
#4 is the idler pulley. When you replace it, you just remove the Torx bolt and swap the pulley with integrated bearing. #7 is the tensioner pulley. It's replaced as an entire assembly.
http://benzbits.com/M112/BeltRouting.pdf
#4 is the idler pulley. When you replace it, you just remove the Torx bolt and swap the pulley with integrated bearing. #7 is the tensioner pulley. It's replaced as an entire assembly.
As I said, I am at ~78k miles, how much is the life of idler pulley and tensioner? Is it a maintenance item to replace them both? Again, I am not having any abnormal noises or squeaking or anything.
Thanks again
Member
Joined: Dec 2012
Posts: 216
Likes: 1
2004 CLK 500 with AMG Package, Not Convertible
I used this you tube video for guidance: How to Replace the Serpentine Belt and Tensioner - Mercedes C240 C320 E320 CLK320 ML320 V6 - YouTube Looks real easy to change your serpentine belt. I used an ice pick.
So if I understand it correctly, for just replacing the belt, use 17mm socket and rotate tensioner ccw and remove the belt, no need to use any Allen key or anything, correct?
Member
Joined: Jan 2014
Posts: 165
Likes: 8
From: Central California
05 CLK320 Cabriolet W209 & 2011 BMW X3
You need the allen key (Or Something Like It) in place to put the new belt back on. This way you can use 2 hands. I took a picture of mine before removing to ensure correct replacement. I didn't want to trust my memory. Don't forget to remove the allen key rotating the tensioner ccw when you are finished with the replacement. This puts the tension back on the new belt.
Member
Joined: Dec 2012
Posts: 216
Likes: 1
2004 CLK 500 with AMG Package, Not Convertible
You need the allen key (Or Something Like It) in place to put the new belt back on. This way you can use 2 hands. I took a picture of mine before removing to ensure correct replacement. I didn't want to trust my memory. Don't forget to remove the allen key rotating the tensioner ccw when you are finished with the replacement. This puts the tension back on the new belt.
Makes perfect sense. Thanks guys
Senior Member
Joined: Feb 2015
Posts: 434
Likes: 16
From: Midlands, UK
CLK W209
Ah I didn't know about the Allen hole to lock it in release, I just put the belt on everything else, then levered the tensioner and slipped it over it, not too difficult to do.
Shall do this when I change my tensioner tomorrow.
Shall do this when I change my tensioner tomorrow.
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Member
Joined: Dec 2012
Posts: 216
Likes: 1
2004 CLK 500 with AMG Package, Not Convertible
Member
Joined: Jan 2014
Posts: 165
Likes: 8
From: Central California
05 CLK320 Cabriolet W209 & 2011 BMW X3
I replaced my original (OEM) with a Continental Elite belt. Continental merged with Goodyear recently. I got mine on Ebay for less than $13 Rock Auto has the same one for $26 Rock Auto has some really good prices though. They are very competitive. They sell a "Belt Drive Component Kit" which includes the belt, tensioner and idler pulley by Continental for $139.79 for my CLK320. I only changed the belt. I always shop around. I generally go to Parts.com for OEM only parts, AutohausAZ, Oscaro, Bosch, Rock Auto, Bilstein.
Member
Joined: Dec 2012
Posts: 216
Likes: 1
2004 CLK 500 with AMG Package, Not Convertible
I replaced my original (OEM) with a Continental Elite belt. Continental merged with Goodyear recently. I got mine on Ebay for less than $13 Rock Auto has the same one for $26 Rock Auto has some really good prices though. They are very competitive. They sell a "Belt Drive Component Kit" which includes the belt, tensioner and idler pulley by Continental for $139.79 for my CLK320. I only changed the belt. I always shop around. I generally go to Parts.com for OEM only parts, AutohausAZ, Oscaro, Bosch, Rock Auto, Bilstein.
I just ordered the belt, more like good to have it.
Senior Member
Joined: Feb 2015
Posts: 434
Likes: 16
From: Midlands, UK
CLK W209
Once they were replaced, I looked at the tensioner and it was wobbling a little, which I thought was a tad strange, so I took the belt off and span the block on the tensioner and the bearings on that we're also soon on their way out.
But you have to change the whole tensioner unit.
And now, the tensioner is still/is not vibrating up and down in operation, so I can only assume the tensioner was past its best too.
They probably had a little life left in them, but I like to keep on top of everything.
MOT on Saturday, but I suspect that it will pass with flying colours.
Member
Joined: Mar 2013
Posts: 155
Likes: 7
2005 320CLK Cab
Dang, wrote too soon. The warm weather is just coming to the North East so I haven't been under the hood yet for anything serious
I get off a plane in St. Louis & wife calls from NJ. She had to call AAA to have the car towed. She had no power, battery light came on she drove it another 1/2 mile anyway. Lovely. Looks like the timing belt is shredded.
Senior Member
Joined: Feb 2015
Posts: 434
Likes: 16
From: Midlands, UK
CLK W209
*auxillary belt. Timing is done via chains on our Mercs. Timing truly would have been a disaster. Don't know how the car would have taken to being driven without the water pump turning though.
Newbie
Joined: Jul 2016
Posts: 5
Likes: 0
CLK320 Coupe
I know I'm late to this thread but I had the same problem not too long ago. Started the car and I heard pully noise. Thinking it was just a pulley to be replaced I drove home. Much to my surprise when I opened the hood the tensioner pulley is halfway off the shaft, with the dust cover and bolt missing. You can buy the pulley alone, but not with dust cover and bolt, so I had to replace the whole assembly. $135 from local auto part store, took about 20 minutes.
Going in I was very nervous about the serpentine belt, but it was so easy. Lots of youtube videos helped.
Going in I was very nervous about the serpentine belt, but it was so easy. Lots of youtube videos helped.
