W209 CLK 320 Brake Woes

iainjo

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CLK/2007/2.2
I've had a long standing problem with the parking brake with the foot pedal not springing back once released. It started with it not coming all the way back up and the light staying on until giving it a little help hooking a foot underneath to bring it up all the way. That developed into it only springing back a small amount when released and when lifted dropping back to where the ratchet starts. So today I took the panel off under the rear seat and gave it a good going over with penetrating oil whilst working the brake. It hasn't made any difference so far, it looks more like a problem with a mechanism that pushes the pedal back up so when it's light I'll dive into the footwell for a look. Any tips on what to look for would be a big help?

Job no. 2 was to replace the rear discs and pads and looked quite easy from what I'd seen. Getting the pads out was the first challenge and try as I might I could not budge the pin holding them in place. As I was getting nowhere fast I thought I'd check the disc. It was easy enough to remove the caliper and gain access and the torx screw holding the disc came out easily enough. Then to the disc, I gave it a bit of persuasion with a rubber mallet and still it would not budge off the hub. I repeated this, giving it as much persuasion as I dare and still it wouldn't move. It would however rotate around the hub, it easily spun round 360 degrees and more with little effort. It just wouldn't pull away and felt is if something was holding it in place. Again, any tips on what to try before I give in and get my local garage to take a look? I've limited space to work on the car, what space I have is on a slight incline so even taking car with 2 jacks and chocks I'm wary about getting under the car for a closer look.
 

joderest

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it sounds very much like the parking brake shoes are holding the disc on, have you tried slackening the adjuster off through the hole in the disc (bolt hole) you may need a torch to see the adjuster.
If this is the case, you must have a large lip on the drum, and if so, disc replacement may well be called for.
If the pads are the same as my ML, then the pins punch out with appropriate size punch.
 

joderest

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regarding the foot parking brake issue, may well be the return spring on the pedal has either come off or broken
 

gassed up

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2011 C207 350CDI;2010 C207 350CDI sport;2010 SLK300;2004 C209 320;2000 C208 230K;
1st problem 1st: You need to start at the rear brake back plates and check/free/lubricate all the linkages and fulcrums. Ensure the cables aren't gummed up. 2nd problem is probably a consequence of the 1st problem, if the handbrake shoes aren't releasing properly they will be holding the drum/disc firmly in place. Wind the manual adjusters back via the access hole and ensure the operating levers on the back plate are free, a little BFI should then have them loose.
 
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iainjo

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Thanks all.

I didn't know about the parking brake shoe adjuster :oops: I'd watched a couple of YouTube videos and I must have flicked through that step. I'll certainly have another go, is it recommended changing anything else? The back plates look to have seen better days and the wear sensors look ok other than one has a chip in the plastic where it's clipped into the caliper.

I'll dig down into the footwell to see if I can locate the return spring.
 

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