W209 CLK Sport Anti-roll bar bushes, bar lateral location & bolt removal.

[Droverunner]

The final mid-life front suspension and brake check-over item on our 2007 CLK (220CDI Sport) Coupe is the anti-roll bar bushes. ARB and bushes look original.. bar is 22mm dia.

First... reading dire warnings on various "how to" guides I've tried to remove each bolt. They all unscrew about 5mm before getting very tight. Can't really see how you would get to oil the hidden end of the threads for successful removal?? Any ideas appreciated. I'd even wondered about drilling holes about 8mm dia in the alloy subframe adj each bolt end to see them and get oil to the threads.

Next... the anti-roll bar has moved sideways to the passenger side about 20-30mm so it's very close to rubbing on one of the suspension arms that side. Is there an unseen lip on the bar within the bushes that should stop this? In the past on other vehicles I've just levered the bar over to a central position and put on a jubilee clip to stop it from sliding through.

 

[Uncle Benz]

The saddle bracket bolts go right through the subframe. If you feel above there is a channel in the subframe and you can feel the long threaded bits poking through. I usually get a good couple of fingers full of grease and massage them into the exposed threads (oo er) before trying to undo them. It is a pain if you snap them off, but it is possible to drill them out and either helicoil or put a nut on the top, in the subframe channel.

 

[thebiglad]

Wind out the bolts as far as they will go easily, then spray the exposed threads with a lubricating product such as white grease, then wind them back in. This will spread the lube into the threads in the sub-frame and ultimately the rusty end of the bolt.

Do this several times and eventually the bolts will come out without drama.

 

[Oldspanners]

The bolts go right through the subframe (on my W203 C class anyway) for about an inch. You can see this from the top on the drivers side and spray penetrating oil on them and then slowly work them back and forward repeating the process. They are also locktited on the threads as well as an inch of rust at the top.
It took me a good half hour to get out one side but as you know you can feel the strain on them and they will snap easily.

 

[LostKiwi]

Wind out the bolts as far as they will go easily, then spray the exposed threads with a lubricating product such as white grease, then wind them back in. This will spread the lube into the threads in the sub-frame and ultimately the rusty end of the bolt.

Do this several times and eventually the bolts will come out without drama.

Absolutely this. Wind the bolt out 1/2 turn, in 1/4 turn, out 1/2 turn, in 1/4 turn lubricating from above as you go. This allows the threads to clear instead of jamming.

 

[Droverunner]

Thanks guys... good and careful re bolt removal as I well the know the pain from the … thankfully few... that have snapped on me over the decades. I'm only using a 3/8th drive short ratchet which limits the force you apply. It didn't look like there was any feasible access to the bolt ends but I was in the middle of other work on the car so will set aside a day and concentrate on getting them out intact.

Any thoughts re the ARB moving to one side through the bushes? I see some models have the bushes bonded to the bar... don't know which ours is yet but assume it was an attempt to keep the bar central?

 

[Droverunner]

Need to bring this to the top again as its getting clunky so having a go at getting these bolts out this weekend. Any extra ideas to those in the posts above. If not I'll just give it my best shot with small turns and constant oiling.

Also anyone know about the last question I asked in post #6 above... Should there be shoulders on the ARB to locate it laterally as ours has moved sideways through the bushes a bit??

 

[LostKiwi]

You could liberally spray everything with good quality penetrating oil such as Plusgas or Duck oil (or make your own with 50/50 ATF/acetone). Do NOT use WD40!

 

[Oldspanners]

Need to bring this to the top again as its getting clunky so having a go at getting these bolts out this weekend. Any extra ideas to those in the posts above. If not I'll just give it my best shot with small turns and constant oiling.

Also anyone know about the last question I asked in post #6 above... Should there be shoulders on the ARB to locate it laterally as ours has moved sideways through the bushes a bit??

Put your VIN into the box at the top of this and then click on the green highlighted tab http://mb-teilekatalog.info/
That will give you exploded diagrams and you can see how the ARB is loctated.

 

[Droverunner]

Thanks guys, yes will use some oily oil in a trigger can as well as a generic plusgas type spray mixed in, and have found the diagrams on that link Oldspanners.

Do you know if the bolts did snap and needed drilling out so threads ruined is there even a tiny access to put nuts on the other side of the subframe?

Reading different threads here and elsewhere it seems I could have a bar with bushes that could be replaced or they could be bonded on and a whole bar with bushes needed. On that parts link for our VIN the ARB comes up as an updated part number and when I Google this it comes up as the bar with bonded bushes (listing by by Mercedes Newcastle on Ebay). Any experience swapping a non bonded to bonded?

 

[Uncle Benz]

There is loads of room for nuts above if you do snap them. Drilling is the hardest part.

 

[Droverunner]

Never have I been more pleased to see bolts removed. Used the short handle 3/8" drive set so I kept the leverage down. Took about 10mins each pair of bolts going to and fro. Even without the bit of corrosion on the exposed bolt ends the bolt and tapped thread in the subframe were lok-tite coated.

Also removed the ARB ends from the drop links so I know those don't need cutting off.

 

[Droverunner]

The source of the clunking was confirmed in that the ARB had moved through its bushes to the nearside by about 50mm and there were contact marks where it had been catching the nearside front upper arm. See images of difference between clearance on nearside and offside in images 2 & 3. I'll message Mercedes Newcastle on Ebay and just confirm their listed bar (A2033234465) is correct and has bonded bushes then order that.

The original bushes don't have the split to enable fitting like aftermarket bushes... I can't tell if they were bonded originally but if they weren't there is no lip on the bar to stop the it moving laterally..

 

[LostKiwi]

Never have I been more pleased to see bolts removed. Used the short handle 3/8" drive set so I kept the leverage down. Took about 10mins each pair of bolts going to and fro. Even without the bit of corrosion on the exposed bolt ends the bolt and tapped thread in the subframe were lok-tite coated.

Also removed the ARB ends from the drop links so I know those don't need cutting off.

View attachment 48988

Good result then!

 

[Droverunner]

Just an update. Car is transformed with the new MB ARB. It's obvious this setup is designed for bushes bonded to the bar as per the new one. See in the second image the way the old one has moved through it's bushes to the nearside once they became unbonded. In the first image note the proper gap between ARB and suspension arm compared to that in post #13 above.

 

[Wighty]

Just about to attempt this myself on the CLK as well as changing the control arms . This was a helpful read . (Thanks Blobcat as well for finding this thread )