I've purchased the backup ring replacement kit from DIYBenzRepair, https://www.diybenzrepair.com/shop/p...plete-kit-32pc, to remedy my sinking front right corner and occasional red ABC WARNING - TOO LOW.

I'm fairly certain that I've seen a front valve block removal video on YouTube, so that needs to be found again. I would be interested in any experience with this effort, especially around correct tools to use as well as where to find and purchase the right sized hydraulic hose caps/plugs. I appreciate any help. Thanks.

 

Having done both front and back the front is much easier because of no "quick connects" to deal with. You will be successful.

 

Any idea of the type or size hose plug to buy?

 

I am about to do the same service on my SL55. Same exact symptoms, except my car is sinking a lot more often - sometimes it takes 2-3 days, sometimes it takes only a few hours. I bought the same repair kit as well.

Since i am at least a week behind you from starting to do the work, please do share your experience and any helpful tips/tools/tricks/video that worked for you. From everything i read and watched, it should not be too bad of a project. Good luck!!!

 

I didn't use any hose blocks. Use plastic bags and rubber bands if you think it necessary which it probably isn't.

 

This may be helpful. It isn't an R230 but it should be similar:

https://mbworld.org/forums/cl55-amg-...ce-repair.html

 

I haven't received the kit yet, but I appreciate the tip on the baggies and elastics, that sounds like the right route!

 

I just did my front valve block a month ago. I snipped the finger tips off of some nitrile gloves and used those to cover the hose ends.

 

Nitrile glove finger tip caps.... BRILLIANT!

 

There is a better answer.
Check out Amazon or ebay or your local parts shop

 

^ Vacuum Caps.
Pentosin destroys rubber (nitrile) gloves. Fluid is viscous and it's not going to last. I tried it. Just much environmentally safer to go with the heavier thick Vacuum caps
Good luck

 

All done!!
I was able to successfully rebuild both of my valve blocks - front and rear.
So far, 2 days later - the results are great. No sagging, no warning lights, no leaks.

I really took my time, even removed the front bumper for better access and visibility, but honestly, it's not a hard project to do. If i have to do it again, it will take me 1/2 the time.

I first did the front valve block. Replaced all seals and the pressure accumulator. I used a brand new Corteco unit. Everything came a parts easily and i was able to put it back together with no issues. I spent a lot of time and effort to properly label and mark every connector and component so things went back where they belonged.
Front took me about 3-4 hours and this includes removing the bumper, lifting up the car, exploring, clean up, etc, etc

The rear was not too bad either. Took a bit less time. The longest i spent was on figuring out how to disconnect the "quick connect" hoses - all 4 of them. I have the special tool from Mercedes but it still took me 15-20 minutes to figure out the logic. The link i am sharing below helped me A LOT.
I installed a new Corteco pressure accumulator in the rear too, but i did not have a new return accumulator (the small one), so i kept the original there. I wish i knew it's right there so i could have ordered it in advance and replaced both of the rear accumulators at the same time. Now i have the return accumulator ordered and in the mail, so i may replace it in a few weeks. It's all preventive with these accumulators, since my car has close to 135k miles and i am not sure if they were ever replaced. Plus my ride was getting a bit floaty and unsettled over bumps lately, so i figured it won't hurt to replace the pressure accumulators proactively.

At the end, i "flushed" about 3 Liters of fresh Pentosin fluid through the system.
My fluid is now pretty clear and very clean. It was kind of dark green before.

I will do one more fluid flush once i get 5L of new Pentosin fluid delivered next week. New 3 micron filter is also on order.


Like i said earlier, this link is pure gold - bookmark it. There are many sections in it, covering everything ABC. It's translated from German, so no perfect English, yet still very helpful: http://translate.google.com/translat...62,15700265#b6


Good luck and let me know if i can answer any questions!!

 

Congratulations on your successful project! From my earlier posts you can see I successfully did the same. After several months, no sagging and all is well. Made my own tool (from a 9/16 open end wrench) for the back. Love the car.

 

Good job! And if I had a dollar for every time I said, " If I have to do it again, it will take me 1/2 the time," I could afford to take my wife out for a nice dinner!

 

I am exploring my ABC as I need to replace a few things., i see valve blocks can be repaired on upto 2006 my. For the 2007's+ there is 1 accumulator on the pump and 2 in the rear for me to replace? I have the 3 microin filter. What causes sagging in the car 2007+ years?
Thanks in advance.

 

Resurrecting this thread. @danmm7
This is what I'm looking at right now (below). My right side is sagging, though it looks like FB1 is a little weepy. I'll address that next.

For now, what are the thoughts on the steps to remove the valve block? This is what I'm thinking:

1. using my air compressor, blow the dirt away
2. Remove pressure via the bleeder
3. Remove the hoses to the block, looks like 5 hoses are connected
   1. T, P, SP, FB1, FB2
   2. Pipe markings: FB1 = left strut, FB2 = right strut, P = pressure line from pump, SP = pressure line to pressure accumulator, T = return line to ABC oil reservoir (reservoir).
   3. Image at http://www.hehlhans.de/sl55amg1/bild...il/puls0-a.jpg appears to show upper connections need to be removed as well
4. I'm not sure which bolts need to be removed, or where the electrical connection is yet

Any advice?
​​​​​​​

 

Now I see why you removed the bumper, not a ton of room to work in there. I couldn't get the service bleeder to open, but it's been up on blocks for a couple of weeks it should be depressurized. Also didn't have a lot of luck removing the hoses, so I've sprayed with liquid wrench.

How difficult was it to remove the block?

 

I've removed FB2 and P as identified in these photos (not mine)


I've removed the upper left hose, I assume a return line?



The problem I have now is, the upper left hose does not stop leaking hydraulic fluid, so I've reattached it.

I'm struggling with FB1 and T. SP is starting to move a little. I'm just not sure what to do about the return line running. I wonder if I need to get that service nipple released.

Any advice from the board?

 

Isn’t SP just the hard line that runs from the valve block to the accumulator? I don’t remember having any trouble with it....but it shouldn’t even be necessary to remove to get the valve block
out of the car, right? Did you remove the accumulator mounting bolts?

look at where the hard lines are running:

https://www.ebay.com/itm/03-06-Merce...ty!92677!US!-1

 

I did that front valve block a few weeks ago. I found it easier to remove the front light, then being able to unbolt the whole assembly including that "bulb" and the bracket that is holding the valve block in place.

 

My main issues right now are that it's difficult to remove the lines. I have a 17mm box wrench in there and without removing those upper lines it's difficult to get to the other hose connections. Additionally, they apparently haven't been moved in 15 years and 62k miles, so they're on there pretty good.

I found that overnight, fluid continued to leak, so I snugged up the lines that I had previously removed.

​​​​@thias Wow, I'm a little apprehensive about removing the headlight. Am I right that the tabs holding the headlight can be brittle? I don't want to break those, but I love the idea to gain access to the area.

 

You need to be using a flare nut wrench.

I wanted a high quality one to avoid rounding off the nuts and bought a used one made by SK on eBay, part number 8815.

I also bought a snap-on 17mm crows foot flare used off eBay, part number FRHM17.

It was easier to get access to some of the nuts with the crows foot, which is why I recommend getting both.

I only replaced the accumulator, and did not remove the entire valve block or all hoses...but I did take off SP without any issues.

 

Good advice, I'll swing through Home Depot on my way home.

 

Did you ever remove the front bumper? It makes things at least 10x easier.
Removing the bumper is not hard and totally worth the time.

Just in case, use masking tape and label all the hoses/pipes, so you do not get confused later.

Wash everything with brake cleaner, (buy a few bottles) before removing connections. Dirt/dust is your biggest enemy.

Make sure car is lifted in the air.

Mark the electrical connections properly. Take pictures often so you can recall later where things go.

It's a messy job (but not hard) and fluid will leak from different places. Just be ready with the right rugs, towels, etc.

I did not release pressure from the lines. The car was parked for 24 hrs before i started the job and this was sufficient. It not run into any ABC fluid under pressure.
The rear valve block was a different story.

 

I did not remove the front bumper, but can see where that would be helpful, just felt daunting. I've been taking pictures all along. The car is currently up on jack stands (wheels were being refinished). Brake cleaner sounds like a good idea, wish I had thought of that before I started. I'll watch the video on YouTube about the bumper removal.