My right rear side of my sl55 starts to sag after sitting for a couple of hours. I'm pretty sure my car is due for a valve block soon. A replacement is around 2k on fcp euro. However, I could try to repair it for much less than that? Does anyone live in the Bay Area/San Jose that knows how to repair this? Also, if anyone has opted for the repair, how is that holding up? I'm not to mechanically savvy so recommend some places that can repair these. Please send some tips and advice, thank you.

 

I have done the rebuild on my SL55 on my own - front and rear. Happy to offer you some pointers. It's it not too bad of a job IF you have patience, some tools and a garage. The hardest part is disconnecting the quick connect hoses (there is a trick and special tool) and removing the valve block. It's located inside in the rear fender area, in front of the rear wheel (behind driver seat area, kind of). You need to remove the rear wheel and the plastic shield inside the fender and you will see it.

First thing you need, is a good set of replacement o-rings. See this: https://www.diybenzrepair.com/reseal...e-block-reseal

You also need the special tool required to disconnect the "quick connect" hose connections. See this: https://www.benzworld.org/attachment...1-jpg.2483588/
Also, read this discussion: https://www.benzworld.org/threads/ab...moval.3015796/

Once you take the valve block out, like bobterry said, you have the option to ship to a shop where they can rebuild it for you (for a fee) or you can get the o-rings and replace them yourself. Cleaning the valves and replacing the o-rings as DIY is not hard in my opinion.

 

I’d love to DIY the repair, but I’m very concerned about the difficulty of removing the valve block to get it on the bench. YouTube videos seem to all show the operation only after it’s been removed.

 

If you can get the whole car off the ground on a lift or on jack stands, it’s really not that bad.

The key is to buy the Mercedes quick disconnect tool and to open the bleed valves at each rear wheel with an 11mm wrench before doing anything else. This relieves pressure on the hoses between the valve block and struts, which makes it possible to separate the quick disconnects easily.

 

When I was replacing front and rear accumulators, I released the pressure with SDS system. Also, after rebulding the valve blocks it would be useful to run rodeo procedure to get the air out of the system.

 

Im trying to do the front block and change a pipe on mine and I've temporarily given up stuggling getting one of the strut lines off the valve block - they are big 17mm flange nuts, there is something in what you say

 

Get a 3/8 drive 17mm crows foot (line wrench style) that attaches to a socket wrench. See pic below, right side.

** Make sure it is line wrench style and not a regular crows foot or you might round off the fitting when trying to break it loose!!**

put a pipe (I use the handle from one of my jacks) over the socket wrench handle to get more leverage.

 

I used a rebuilder I found on Ebay, he was located in Las Vegas, charged $150 including shipping. The valve block came back in perfect condition, sealed and cleaned. It's been over a year and no problems. The front block is easy to remove, except for the large 17mm line. I had to try several 17mm wrenches before finding one that fit tightly. Do not use cheap wrenches, The rear one can be more challenging, but if you use the tool to disconnect the lines, it should come out with little effort. I highly recommend the rebuilding service. Good Luck

 

Seems like a pretty good deal, particularly since the rebuild kit alone costs $50+.