Broken spring

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Stratman

MB Enthusiast
Joined
Jun 15, 2003
Messages
5,820
Location
Sunbury
Car
W203 C200 CDI '04Estate
After too many boing boing noises from the rear of my W203 estate I finally got underneath and found the cause, a broken coil spring. Looking at Youtube's finest mechanics I'm happy they can be changed without a spring compressor, by lowering the bottom arm on a trolley jack after removing the inner pivot bolt. This leads to a couple of questions.

Is the orientation of the inner bolt important? By which I mean is it used to set a suspension parameter?

Where is the best place to buy new springs? I'm guessing MB but fully expect to be fleeced. Is there an alternative?

The springs are coded with two yellow markings for the spring rate, if anyone is taking notes ;)
 
I`ve used the same method as shown on Youtube and it is really quick and easy.

The inner bolt is just a round bolt with no groove/cam washers etc attached therefore orientation doesn't apply.

I bought new sachs springs from eurocarpats. They were the same length but the wire was a smaller diameter and the car was slightly lower after fitting. I solved this with thicker spring seats which I had in the garage anyway. With hindsight though I wish I had bought my new springs from Mercedes.

Hope that helps.
 
Thanks gentlemen. It looks like a trip to Brooklands is in the offing.

I wonder what I can do while waiting for the parts counter to get into gear :D
 
Brooklands parts counter is surprisingly speedy ...

Always some crumpet around to watch too.
 
I find undoing the outer bolt easier, the bolt hole can be a pig to line up taking out the inner bolt as there is no movement in it apart from up and down.

Hard to explain in a post but just talking from experience, I have done both rear springs in 30-40 mins.
 
I just gave my local benz parts counter here in essex my vin, he gave me the part number for the front and rear springs and i gave them to carparts4less and they gave me the equivalent sachs items, plus you get £15 off if you spend over £100, Eurocarparts will do so also.

Oddly the rear springs on my 124 coupe were much more expensive than the fronts, I had always imagined it would be the other way round
 
MB Weybridge (MB World :D) have them in stock so I'll be collecting a pair this afternoon. £167 for the pair, including VAT. Expensive, but at the upper end of my acceptable range. Mind you, it makes Scottydee's price look like an absolute bargain! How long ago was this?
 
MB Weybridge (MB World :D) have them in stock so I'll be collecting a pair this afternoon. £167 for the pair, including VAT. Expensive, but at the upper end of my acceptable range. Mind you, it makes Scottydee's price look like an absolute bargain! How long ago was this?

Ask them for some discount, 10% minimum :)
 
I favour the drop the lower arm method. With a little care it is a lot easier, quicker and safer than wrestling with the approved style spring compressor.

However, the following tips are essential to do the job safely:

The rear of the car should be as level as possible, use stands under the rear sill supporting points. Do not attempt to try doing it with just one corner raised, it will make it much more difficult to get your lowering jack correctly lined-up. Remove the road wheel.

Release the handbrake and disconnect the bottom of the damper before you attempt to remove the inner bolt. You will need to remove the plastic arm covers to get to the damper bolts.

Place your trolley jack under the inner end of the arm and think about which way and how far it is going to move, bearing in mind the arm could drop about 45 degrees so the trolley jack will want to move outwards about 15 or 20cm. Also make sure that the end of the arm is not going to slip off the jack as it changes angle. Raise the jack until it just starts to take the weight of the car.

Now you can remove the bolt, once the nut is loose it should move out easily. If not check that handbrake again.

Start to lower slowly, you should see the hub rise upwards (I think it pivots on the antiroll bar link). You should find all tension in the spring is released by the time the inner end has dropped 4 or 5 cm. Check the state of the spring by giving it a gentle tap with the handle of a screwdriver, you will know when the tension is released. Keep on lowering and the spring will just fall out.

When refitting, note then the bottom end of the spring has to be correctly located with respect to the step in the pan. The upper end sits in rubber cup, also stepped. The rubber cup is easy to pull out assuming it does not fall out with the old spring.
 
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I did them a disservice, they were only £162.

Bargain. No discount as I'm no longer a member of the official MB club. This forum buttered no parsnips :(

While I was there I took a couple of snaps of the gorgeous S500 Coupe. I'll post them in the Good Looking Cars thread in GD.
 
All done.

No great surprises apart from the sheer weight of the spring. Everything was pretty much as Youtube and SLKNick said. I did the broken one first following the instructions, the other one I tried without removing the bottom damper bolt.
It does need to be removed.

Thanks to one and all for your advice.

Thinking about it, there were a couple of small surprises.

The inner pivot bolt is 18mm and the bolt head does need holding still while the nut is being removed. Guess what size spanner most sets don't include? A trip to Halfords was needed.

On the the passenger side the exhaust pipe is right behind the inner pivot bolt head. A second trolley jack (a man can never have too many) and an ice hockey puck (£1.60 from Amazon, highly recommended) to cushion the contact moved it out of the way far enough to withdraw the bolt.
 
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Glad it went OK, sorry forgot to warn you about the exhaust.
 

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