hi guys, any ideas if the 08 w216 ABC valve block can be rebuilt or should i replace the whole valve block? i have oil and pressure leaking from the longest ones

see attachments if it helps

thanks in advance

this part is leaking from its base

 

I have not looked a lot at these since my system has not yet failed, but this place in Germany rebuilds them...https://abcteile24.de/en/produkt-kat...ntileinheiten/.

At 15 years old, all the parts in your system will soon need replacing, so you might as well do all you can.

 

thank you for the info, and yes at a certain point all parts has to fail some day,

i have discovered also that these valve block doesn't have a manufactural number, so you can't buy them separate from the whole block.

for now i have these information

 

https://www.diybenzrepair.com/shop/a...sic-14pc-4636a

 

Hi Chris,
Thank you but it is not the same block valve, and nobody till now figured out how to separate the blocks from the aluminium part to see inside.

If anyone knows, kindly share some photos
Thank you

 

theyre caps you lift them with a flathead, they're plastic, the solenoids are friction fit inside the block using o-rings, then you replace the gaskets on the caps on the reinstall.

 

i understand and thank for the information about the older version and respectfully i'm aware how to replace the ring
but i have the later version of it and if you closely look at the plastic caps, there is an electric plug coming out from it (i think it connects the 2 block together)
the plastic cap is so fragile and i am concerned that if i try to lift it i might brake it in peaces
i'm just asking to see the blocks and the electrical connections inside so that i'll be careful when lift it, if anyone have ever split it before
requesting some photos

 

Sorry, can't help with photos, but will emphasize that the plastic stuff is REALLY fragile, as you mention. I have found repeatedly on my car that the plastic stuff is just crumbling due to age and temperature cycles. You are right to be concerned. I was going to change my fuel filter, and opened it up to take a look. The connectors and wires looked so fragile that I took it to the dealer to let them do it--better they have to fix it if something broke than me. It oddly cost 1.8 hours of labor, even though ASRA says .8. Not sure why or where the extra hour of labor came from. Regardless, probably took them 10 minutes start to finish.

 

Hello,

I have a 2009 w216 cl65 and do not have a leak yet like you did. Did you ever figure out how to rebuild the second gen abc valve body on your car? Were you able to open and separate the plastic cover with the electrical connector? I have a hissing sound on mine internally and I believe that the valve block has internal leak. I replaced accumulator and bleed the system few time via rodeo and cockpit switch raising it up and down 20 times. I don’t have any codes and leaks however.

 

Did you ever figure this out? Did you look inside the valve block?

 

I have not figured out how to get into one of these. I contacted Rapa who is the original manufacturer, but said they couldn't provide me details because they are just a supplier. With no information available online to take apart a second generation valve block, one of us is going to have to break one open and find out how they are put together. On the one hand, they must be pretty reliable, since there is not a cottage industry regarding replacing internal parts, but on the other hand sooner or later these will fail and it would be nice to know how to fix them.

 

Hi, Nath,

Thanks for the reply, damn I am just wondering what would cause this hissing sound. Could it be anything other then the front valve block? I mean it is happening inside the block which means the seals are causing air to escape when is not suppose to. Or could it be from the pump. There are no visible leaks or error messages anywhere. I don't know what else to make out of it. I am hesitant to break mine open as Mercedes is not currently offering the valve block anymore. Kevin who makes seals for the old valve blocks says that he was chiseling through epoxy to try to get the valve solenoids to separate and just stopped after a while. Seems to not be a way made for them to be removed or rebuild. I dont know how abc specialists nl sells hand rebuild valve blocks. They would not share any info.

 

I became curious about this issue after our last posts and purchased a valve block just to destroy, and see what's going on inside. I'm eventually going to do a larger ABC project, and it would have been great to have replaced the seals inside the solenoids. However, I can tell you with certainty that one cannot get into a valve block. It is about the sturdiest thing in the known universe. I started small by putting it in a vise, and seeing if I could tap one of the towers a little askew so I could get a pry underneath and lever it off. Nope. Then I took a Dremel and cut a ridge in the bottom to try the same thing--nope. I then made large vertical and horizontal Dremel cuts in the black plastic, and finally was able to pry off plastic. Underneath there are more metal towers that insert into the valve block, with some electronics at the top of the tower. More tapping to dislodge the now metal towers--nope, no movement. I then got violent and took a 4 pound sledge hammer to it. Still no movement! I smashed and smashed and no movement. By this time, I thought I was going to hurt myself and stopped. Plus, there's no way I'm getting into a different block to replace seals. My hunch is the supplier uses some sort of massive press to put the towers into the block, and hand tools will not overcome this pressure. The refurbs people sell--no way have they opened the solenoids. They just cleaned it up, maybe replaced a pressure sensor, maybe replaced the accumulator (front). The project was of no value in the end, except to guide me to not buying a refurbished product. Thankfully used parts are plentiful. This might be one thing worth paying up for and purchasing a real new MB part if they become available. I believe this part was used until 2020, so one would think they should still be supplying replacements.

 

Hi Nath,

I was about to do the same thing and thanks for this information and hard work in tackling this. It confirms what Kevin stated that valve solenoid are also somehow epoxied in. Hmm. I would purchase a new valve block but they are unavailable. You are correct all the w222 and w217 s65 come with abc and being unavailable its so strange. What do you think could cause this hissing sound coming from circled area in the front valve body in the photo below ? I dont have leak from the valve block. I replaced the pulsation dampener on the pump when the whine started and also put in new accumulators front and back oem. I might have not heard the hissing sound prior cause of the whine noise. But not it has a hiss and also when car shuts off for about 20 seconds.
1)Do you think seals are not sealing inside? Car level is stable I don't have any codes and don't have any sides sagging at all.
2) Pump might have had a weep leak and I am in process of rebuilding it. I managed and sourced the Rex oem pump seals. It looks clean and great inside the pump but seals are deteriorating and some are frayed. This must also be happening in the valve blocks. So the question is could the tandem pump induce hiss at the front valve block if it has a small weep leak?
3) Is there a way to clean valve block with sensors out? If they are available for purchase I would replace them with new seals? They all show as same part number quantity 3
4) What is the circled piece in my picture that looks like a hex metal plug? That's where the sound is the strongest. It does not list as a part in epc
5) Whats the proper way to completely get rid of air in the valve block? Is it raising car as per wish 15-20 times. Run rodeo and flush system with 2 filters? How do you do it?

 

Firstly before I say anything, I'm no expert. I've got Xentry and this is my hobby, but there are plenty of people on these forums that know more than I do. With that said, have you used a mechanic's stethoscope to listen to the area to identify the hiss? Could it just be a bad O ring from the connection seal in the area circled? I'm not sure what the plug in the circle is or does. If the hiss is not otherwise causing functional problems, maybe time to just forget about it until the problem presents itself more clearly? I've learned to live with uncertainty on my car, as things are not always clear right away. The hiss suggests pressure leaking out of the system at shutdown. I'm not sure how loud this is, but is it possible it is normal, as pressure does release after 15 minutes or so and it has to go somewhere?

Not sure why MB does not have the part available. My part counter guy says part availability is bad in general, and the old rule of thumb about support for 10 years no longer applies. Everything comes from a central warehouse, or Germany. I've purchased many very low inventory parts or last in world parts. Many parts will no longer be made ever again.

Regarding cleaning the valve block...I taped off the electrical connectors, and sprayed it down with P21S Auto Wash. I first drained out all the bad fluid, letting it sit overnight moving it at various angles to drain out everything I could. I then flushed the block with new fluid, although not much would go in without pressure. The sensors easily come off, and there is no seal. Rodeo is the best way to get air out, although it is hard on the system. The WIS instructions actually say to just use the up/down button for some ABC work. My plan is that I bought a low mileage rear valve block to have on the shelf as a replacement, and I'll put in new sensors. I also bought a new front valve block to have on the shelf, and would also buy new sensors if it goes in. In hindsight, I wish I would have waited for low mileage valve blocks from newer cars, like finding some off a 2018 or the like. My rear was a 2011 w/ 37,000 miles, and the front was a 2009 with 90,000 that looked cosmetically in excellent shape. I thought I'd be able to break into it to rebuild it, but we now know that is wrong.

I'm curious about your pump rebuild. Please post details here if possible. Mine was replaced in 2019, so it probably has a few more years. Did you remove the pump to replace the pulsation dampner?

 

The hiss is definitely abc suspension and valve block related. I noticed it for the first time after I removed the pump to change the pulsation damper cause of whine noise and per mercedes tsb. At that time I also replaced the front and rear accumulators as well. I noticed small leak at the bottom of the abc tandem pump not too long ago and decided to rebuild it and remove it. Now I am unsure if air can show and be heard as a hiss at the valve block if abc pump is leaking? I have not tested and installed everything yet as I wanted to address the valve blocks as well. I am replacing the high pressure hose as well since I am at 65k miles anyway and what nearly 15 years old now. When I removed the pump I noticed that the seals inside are deteriorating. Same must be happening at the valve block as well. Well the hiss is there when the car is running as well, and its located at the valve block. It hisses for only 20 seconds after the car is immediately shut off. Then hiss stops. Would you happen to know what's the torque specs on the 3 sensors in the valve block? Guessing 20nm. So you never removed that hex plug I have circled to see what's inside?

I will post a more detail reply and photos regarding the pump rebuild, as I am in the process of still cleaning it which I will put all metal pump components through ultra sonic cleaner. I still have to figure out what kind of sealant or Loctite mercedes used on the 7 piston cup hex screws of the pump. In addition, I have to figure out what are the torque specs for these 7 hex screw cups, I don't know? Guessing 40-50nm of pressure according to my hand feel when I removed them. New sensors are unavailable either. So I would have to reuse mine.
As to having a leak at the o-rings from the lines at the front valve block, I hear no hiss on any of the lines and I replaced all 6 o rings when I removed the valve body for accumulator service. I will replace them this time around as well when I remove the valve body. Its so strange I don't know if this hiss is normal I don't remember having it before.
Some people experience hiss at the pump as well. I don't. Even though mine had a slight leak there is no more whine noise or hiss at the pumps location after the pulsation damper replacement. I guess I will clean valve blocks best as I can as well and try to reinstall everything. If hiss persists then valves seals inside are not sealing. Praying Mercedes gets new valve blocks available and I will replace all at that time including all hoses.
Could you supply some photos of valve body with sensors removed?

 

Yes, I'll get some photos and look up the torque specs. You have me curious to see what noises my system makes upon stopping the car. It snowed here last night so I won't be driving it today, but will do that in the near future. I'm glad to hear there is someone else out there like me working on an old CL. If you really want to get a new front valve block, you can, but it will cost you. I looked up ABC Teile 24 in Germany to see if they rebuild the blocks. They don't, but they have one new one in stock. The photo shows a rear valve block, but the part is indeed a front....https://abcteile24.de/en/produkt/ven...r230-r231-neu/

 

I found that site too but on the photos it looks used. I am skeptical to spend that much on possibly used part. I don't know will wait for Mercedes as I could get it through them once available for $1400 including accumulator and sensors all new front and $950 rear valve block through my wholesale account. I spoke to the parts department and he stated that they are producing more! We just have to keep checking back in once a month and see when they become available. Thanks to you, we now know without special press there is no entrance inside these valves and maybe they are not repairable. I will clean valve block and reassemble everything again do a thrall flush and see if hiss persists. At that time I can load a video of it so you could see.
Yes if you can post photos and get those torque values would be great. I will take photos of all pump components and parts as well as where you can order pump seal kit for $80 and if it holds good as they claim they get it directly from rex manufacturer. I will also write a detail post of it.
When you assemble valve body do you prefill it with fluid best you can or is irrelevant as high pressure will get rid of air bubbles as its bled with rodeo?
Could you remove the hex plug that's circled in my photo and let me know what behind on the valve you are using as an example that you grinded and tried to open up?

 

I could not find a torque spec in WIS for the pressure valve solenoid. I'd probably do 20nm, and you could always tighten more if leaking. I looked at the metal plug, and see that I could remove it, but don't want to now...might do that experimenting with an old part later. I don't think you could get much fluid into the valve block before installing, but I'm sure it would not hurt. Here is a photo from the destroyed rear valve block...

 

Hi everyone, I would love to get some help on my valve block leak.
The car suspension is fine, drives fine, no lights and has pressure. However the reservoir is empty after filling it full after a drive. I have been topping it off every other day.
The leak only happens after driving. I can see that its coming from the valve block where is circled, or below that part. It seems strange because there is no opening there. Please let me know what you guys think.
Thank you

 

Have you checked the accumulators on these cars? There are 3 including pulsation damper on pump. Or you must have a huge leak somewhere.

 

I wouldn't drive the vehicle until you get this sorted out. Running your ABC pump dry would result in things breaking. Can you see a drip while running? My hunch is fluid is escaping at the connection point above where you circled. Maybe the O rings have dried out and letting fluid get by. Maybe start with new lines running to the block? If your lines are original, you'll need to do them eventually, anyway.

 

Hello, How did you remove the epoxy mold from the valves? And are the valves removable so i can replace the O rings since its leaking from its base? Thanks!

 

Nath wanna chime in?
We found they are not removable. Nath here was the one who tackled this disassembly. Not designed to be removed without special tool and clamps and as you see its epoxied. My hiss was fixed by valve body replacement. I went with new one and its great so far no more issues.

 

Hi, first, thanks for the fast replies,

So do you know the correct O-ring size for the hydraulic lines that goes into the valve block. I only found the green ones part number and size (8.2x1.78). I cant seem to find the upper ones (black and white).