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Is there a means to bench test an ABC valve? There is debris (presumably from a ruptured acccumulator) in one of the valve ports. I suspect that this has probably killed the valve/solenoid but if it could be tested, would like to do so before replacing. See photo for the debris at my finger. Debris at finger
Figured it out, found another thread about energizing with 12V. Surprisingly the valve actuates fine. I ended up getting a replacement, knowing that there are rubber shards within the port.
The debris is a bad sign and may mean that the entire system needs to be flushed out and all solenoids checked. Sorry to hear. Getting replacement is likely the best option unless you find a way to fully clean them out.
Good luck and keep us posted.
Any suggestions to flush, aside from the typical procedure? I did inspect all valves, replaced the orings and bench tested. That was the only one with apparent issue. It also corresponds to a strur that had no movement.
Since the valve blocks have both feed and return lines, the system is mostly self flushing when active. This is why the "Rodeo" is the standard procedure, although raising and lowering the car from the buttons also adds a lot of activity. However the lines from the valve blocks to the shocks are single lines and debris could stay in them, just pushing back and forth a bit. Each strut has a bleed line near it which could be used to flush most of those strut lines. There generally is at least a bit of pressure in them which both requires some care, but also keeps air from being sucked back in.
From personal experience, DO NOT, repeat DO NOT open these bleeds when the engine is running. I had been warned, but was also anxious to completely bleed the single lines to the shocks. It resulted in an explosive shower of 3000 psi fluid.
If not already, you should replace the ABC filter and as much fluid as possible several times until you are confident all the debris is out. Have you already replaced the accumulators?
Thank you. yes replaced three accumulators. The two primary were long gone. I have 10 liers of Penrosin and a filter. Was thinking about getting another filter to install after some miles are put on. I like the suggestion to flush at each bleeder. I had done that already but it may be benficial to repeat numerous times in hopes the crap gets purged.
Originally Posted by mrvedit
Since the valve blocks have both feed and return lines, the system is self flushing when active. This is why the "Rodeo" is the standard procedure, although raising and lowering the car from the buttons also adds a lot of activity. However the lines from the valve blocks to the shocks are single lines and debris could stay in them, just pushing back and forth a bit. Each strut has a bleed line near it which could be used to flush most of those strut lines. There generally is at least a bit of pressure in them which both requires some care, but also keeps air from being sucked back in.
From personal experience, DO NOT, repeat DO NOT open these bleeds when the engine is running. I had been warned, but was also anxious to completely bleed the single lines to the shocks. It resulted in an explosive shower of 3000 psi fluid.
If not already, you should replace the ABC filter and as much fluid as possible several times until you are confident all the debris is out. Have you already replaced the accumulators?
Any suggestions to flush, aside from the typical procedure? I did inspect all valves, replaced the orings and bench tested. That was the only one with apparent issue. It also corresponds to a strur that had no movement.
check out the legit street cars video where Alex is working on his CL 65. He was chasing ruptured rubber for weeks It seems. In that the fluid can completely recirculate in the system, rubber can be everywhere if it was small enough to get through the valve blocks.. so this may require a front to back connection and flushing of every single part of the system. Obviously start closest to the accumulator and work out from there, but if it’s gotten back to the filter in the reservoir, and this was a right rear accumulator, that rubber has gone a long distance.
this is why any car with any type of accumulator needs to be maintained preventively
Last edited by Baltistyle; Jan 1, 2026 at 05:54 AM.
Well the saga continues. Put things back together, started it up and nearly immediatly gotta pretty good pop and a good dump of fluid. The control solenoids popped off. Couldnt grasp this as I was super diligent in making sure they were properly seated. Searched and found a thread where someone mentioned how the exterior housing spins separately from the interior valve body. I confirmed that this was my issue. There is slight resistance but the black housing turns indepently,gving the impression that the locks are aligned. So lesson to those rebuilding your valves, put the valve into the block, mating the male/femaile squares and twist to see if the exterior housing slips.
Not sure how this condition developled, could have been when the valve was removed, perhaps the lock was stuck to the block, may have been on install and not having the valve fully inserted when twisted to lock or potentially they are flat out worn/faulty.
Going to reassess. This SL is new to me so this may be a can of worms. As much as I like the ABC, coilovers may be the better option.
Both interesting and very concerning. I just rebuilt my spare valve block and plan to install it shortly as one rear corner sags after a week.
I found the clips that lock the solenoids in place to be very marginal, perhaps just cheaply made. While is sounds like your solenoids (which you often called "valves") had a loose outer case, your post also makes me nervous about the locks.
I assume you are purchasing new solenoids then?
Two years ago I bought a rebuilt valve block on Ebay for about $300 to have as a spare. When I rebuilt my ABC a year ago, I installed the Ebay valve block even though the original was working perfectly. Partly to test it. The Ebay valve block worked perfectly for about 6 months, but then allowed one wheel to slowly sag. I also bought a rebuild kit and started rebuilding the original valve block. I decided the original white rings were better than the rebuild kit's "split rings" and therefore only installed new o-rings, although everything looked perfect. Since the original locking clips broke during disassembly, I used the new ones, but don't have confidence in them. I think I will add duct tape around the solenoids to ensure they don't move. (Well, at least the out shell doesn't move.)
I have another set of valves/solenoids, now waiting on orings. In thinking about it, I wonder if I might have not had the orings sufficiently lubricated when installing. Not sure on this. I did rub CHF all over fthe orings but perhaps that wasnt enough causing them to lock up, compromising the bond between the outer casing and solenoid/valve. I did see a video with a guy that used vasoline. I dont think I will go that route but maybe fill a cup with CHF and let the valves sit in it for a minute before install.
Originally Posted by mrvedit
Both interesting and very concerning. I just rebuilt my spare valve block and plan to install it shortly as one rear corner sags after a week.
I found the clips that lock the solenoids in place to be very marginal, perhaps just cheaply made. While is sounds like your solenoids (which you often called "valves") had a loose outer case, your post also makes me nervous about the locks.
I assume you are purchasing new solenoids then?
Two years ago I bought a rebuilt valve block on Ebay for about $300 to have as a spare. When I rebuilt my ABC a year ago, I installed the Ebay valve block even though the original was working perfectly. Partly to test it. The Ebay valve block worked perfectly for about 6 months, but then allowed one wheel to slowly sag. I also bought a rebuild kit and started rebuilding the original valve block. I decided the original white rings were better than the rebuild kit's "split rings" and therefore only installed new o-rings, although everything looked perfect. Since the original locking clips broke during disassembly, I used the new ones, but don't have confidence in them. I think I will add duct tape around the solenoids to ensure they don't move. (Well, at least the out shell doesn't move.)
Personally I doubt that the o-rings caused such a strong bind that the outer casing came loose. A tiny amount of lube on the o-rings should be fine. I (and others) use Vasoline when rebuilding automatic transmission to temporarily hold parts in place. See no value in your case.
Job is done.Happy to say the ABC is functioning as intended. I recently bought this car, with known ABC issues, so I was fairly concerned about where the ABC issues would take me. I will say the rear valve block is a true PITA. I tried using the quick disconnect tool and did not have any luck as it bent the sleeve it was supposed to push. Fortunately, I only damaged some scrap fittings that were attached to the used valve blocks I had bought.
The loose housings persisted on multiple solenoid valves. In the end, I bought 3 additional valve blocks with valves and 4 out of 10 control valves had this issue. The issue was present on disssemby of some of the receintly purchased replacements, so not necessarily and install issue. So do yourself a favor and check for slipping before rebuilding. I did dip the valves in a cup of CHF prior to installing into the block. I would say that it helped, but I may have been a little conservative with the lube on my first attempt. I did end up tearing one of those white spacer rings. Fortunately it just felt odd on install, kind of a crisp slip as it seated into the block, otherwise it would have gone unnoticed only to rear it's head as a future issue.
Interesting and troublesome that so many of the used valve blocks you purchased had solenoids with loose outer shells. Was it only the shorter ones or the longer ones or both?
Glad you got it all working now though.
Good luck with your PSE issues. What are they? Just a few items not working?
It was just the larger/control solenoids/ No issues with the smaller.ones.
My PSE pump cycles continuously. Getting error messages everywhere (MC seats, cental locks, trunk soft close). Not sure what to make of it. I pulled the pump motor and checked the pressure output and it seems solid (using a ball pump gauge it pegged the needle at 30 PSI. The technique is limited but I have some condidence that's not the issue). I took apart the soft close at trunk and it is holding air just fine. Also I blew through the lines from the manifold, there is free flow at each door lock, so I need to pull the door cards to investigate, but the locks do work.The passenger MC seat works fine but draws an error message. The driver seat doesn't respond at all. I know the bladders are intact, as they held air when tested from manifold behind the seat. In many ways, thisgs don't add up. This car is a bunch of puzzles stacked upon one another.
Originally Posted by mrvedit
Interesting and troublesome that so many of the used valve blocks you purchased had solenoids with loose outer shells. Was it only the shorter ones or the longer ones or both?
Glad you got it all working now though.
Good luck with your PSE issues. What are they? Just a few items not working?
So far my PSE works, although the massage seats don't work because the bladder leak.
I Googled "mercedes r230 pse pump pressure" and the AI summary lists that typical pressure is just 10-14 psi. I expected much more.
So I guess that if there is a leak and pressure drops below 9.4 psi the pump will turn on again. Since you clearly have a pressure gauge you can monitor it. In a very quiet garage you might be able to hear the leak.
It was just the larger/control solenoids/ No issues with the smaller.ones.
My PSE pump cycles continuously. Getting error messages everywhere (MC seats, cental locks, trunk soft close). Not sure what to make of it. I pulled the pump motor and checked the pressure output and it seems solid (using a ball pump gauge it pegged the needle at 30 PSI. The technique is limited but I have some condidence that's not the issue). I took apart the soft close at trunk and it is holding air just fine. Also I blew through the lines from the manifold, there is free flow at each door lock, so I need to pull the door cards to investigate, but the locks do work.The passenger MC seat works fine but draws an error message. The driver seat doesn't respond at all. I know the bladders are intact, as they held air when tested from manifold behind the seat. In many ways, thisgs don't add up. This car is a bunch of puzzles stacked upon one another.
I had an issue with my pump and was getting errors from the passenger seat. I fixed my leak using this video.
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Slideshow: A one-of-one U.S.-spec Mercedes-Benz SLR McLaren Roadster became even rarer after a factory-backed transformation at McLaren's headquarters.
