C270 Suspension Knock

[James100474]

Hi all, just purchased a C270 CDI which knocks when on a slighty rough surface. Have replced worn roll bar bushes and links. All joints seem to be ok, any ideas. Thanks.

 

[television]

Hi James, you only have the ball joint and wheel bearing left, Sometimes you have to use a bar to check for movement in the suspension joints., the wheel bearings can be felt with jacking the car and rocking the wheel.

Malcolm

 

[Uncle Benz]

On the W203 instead of a lower wishbone you have a couple of aluminium link arms. They each have a large bush on the inner end. They are both prone to wear - quicker if wide tyres are fitted - the forward arm bush wears quickest and the internal design of the bush contains a metal crucifix shape. Any weakness in the rubber of the bush allows the crucifix to bang against the outer sleeve of the bush. I reckon this is where your problems lie. I have changed these bushes at around 65k on cars with standard wheels. AMG type wheels help to knock the bushes out as quickly as 40k. Hope this helps.

 

[John Kerr]

Is it possible to change these bushes with ordinary tools or would you need a press

 

[Uncle Benz]

I always use a press because I have one. It would be difficult to do them any other way, since the bush is steel cased, but the arm is quite soft aluminium. I'm not saying it can't be done another way but a press is easiest. If a customer came into my place with the arms and bushes I would certainly do the job for them for the price of a couple of beers. Worth having a ring round some local garages to see...

Orientation is important - there are some datum marks to be observed when fitting the new bushes.

 

[HelpThisDude]

Hello Guys, just curious, how do you remove the ball joint pictured. It looks like there is only 1/2" clearance to lift it before it will foul the strut
I can see a few options, but I'd rather know the easy was first time
Cheers All

 

[John Kerr]

Hello Guys, just curious, how do you remove the ball joint pictured. It looks like there is only 1/2" clearance to lift it before it will foul the strut
I can see a few options, but I'd rather know the easy was first time
Cheers All

You have to unbolt the strut and move it out of the way also the drop link.

 

[HelpThisDude]

You have to unbolt the strut and move it out of the way also the drop link.

Thank you for the reply, but forgive me for silly questions here (never unbolted a strut before ).
Would I remove the two bots from strut to hub, and the nut&bolt from barcket on strut (just above the brake disc), to the top of hub.
If I unbolt these, would I not need to compress the coil spring?

 

[John Kerr]

Thank you for the reply, but forgive me for silly questions here (never unbolted a strut before ).
Would I remove the two bots from strut to hub, and the nut&bolt from barcket on strut (just above the brake disc), to the top of hub.
If I unbolt these, would I not need to compress the coil spring?

The coil spring is secured by the top mount,if you take out the two bolts that secure the strut to the hub and also the mount for the anti roll bar link you will then be able to remove the ball joint with the link.

 

[BlackC55]

Be careful when undoing the roll bar mounts as the thread can come out with the bolt or worse, snap.

Happens all the time!

 

[Cole@MBS]

Doesn't it olly!!

 

[HelpThisDude]

Spot on guys, one bolt just wont budge!

Experience tells me it will snap. I have tried the usual stuff with no luck.
Curious as always, how would you guys deal with it?
It looks like there is a captive nut in the other end but im not sure. Does not look like a easy 'snap off, drill and tap' fix.

 

[Cole@MBS]

Can you get any WD40 on the thread, soak it overnight!!

 

[HelpThisDude]

Will give it a go next time I get a dry day off, cheers buddy.
Just wondered if any one has snapped one off, how did they fixed it?

 

[HelpThisDude]

It’s been a while now, and from time to time the offending bolt has had a good spray. I had an MOT a few days ago and the ARB Bush came up as an advisory, but my car passed.
So I’m ok till March 2010 (except for the rattle that drive me nuts 4 hours a day). I was advised that if the bolt shears, there is no hope other then to replace the Sub Frame! That’s a bit terminal is it not? Is this the case?

 

[television]

Buy a can of pipe freezer from you plumbers merchants, like heat these things work on a shock principle, get it really cold, if you use the whole can it will still be cheap.


Doing a bolt up a touch can free it, not enough to break it

That bolt can be drilled out,but still a subframe off job

 

[HelpThisDude]

Cheers Malcom. Ill give it a go.

 

[HelpThisDude]

Still wont budge....but I can see the top of the bolt so I may well just snap it off and drill straight through. Thanks for all the advice.