Still not sure which one, but lots of fluid around the rear-left valve block. Tow truck picks the car up Monday.

Fun.

 

Are you going to replace and repair the hoses by yourself?

I have some intel regarding the parts to get :-)

 

I have dealt with this. It REALLY is a DIY project if approached properly. Having experienced this failure on my 2001 S-600, I offer the following suggestions. There are 3 hoses on the left side-- from the valve located right side by fuel pump. to the accumulator behind the rear muffler. You must drop/remove the rear exhaust pipe and muffler to do this. This is the devil to remove, requiring dropping rear subframe a couple of inches-- This hose costs about $200 at the Dealer. Change the rear accumulator while in there about $150 from Europarts.
The 2nd right side runs from the valve assembly to the top of right strut. , Clean the 'quick connector' with brake -cleaner (The outer shell MUST move freely to take these apart )-clean and lubricate copiously. I recommend you take this hose(and other hoses) to a good hydraulic shop and replace the flex hose. Cost is $35 to $100 each--much less than 50% of new parts.
While 'in there' with rear subframe dropped, do ALL the hoses on both the left and RIGHT sides. You can re-route the hoses for your convenience rather than duplicating Mercedes's tortuous layout. You will save more than $1500 in hose costs
dong them all. Reason: ALL the flex hoses are bare steel wire reinforced. Mercedes weatherproofing rubber deteriorates and cracks, allowing moisture to enter and rust the steel. ANY FLEXING will cause the rusted steel to break, causing the hose rupture. ALL the hydraulic hoses WILL require replacement to avoid rupture. I retrofitted 'Coil=Overs' to eliminate the entire ABC system when I first realized this fault when the 2nd hose ruptured. I regret now doing that rather than just rebuilding all the hoses.

 

Don't be coy!

Car's on the wrecker right now, will have it in the garage shortly then I can find out which hose went pop. While I'm there I might pull a bunch of hoses and take them to a hydraulic shop to reman all of them and make them reliable/good.

 

 

Rear left valve block, found the hose that popped. There appears to have been some rust. Took the left panel off, but have to lift all 4 wheels off the ground most likely to do this right. Hopefully I can go to the hydraulic shop today and have the car running again tomorrow, but that depends mostly on me.

 

https://www.crossco.com/resources/te...draulic-hoses/

 

There is clear red rust/oxidation on the hose that popped.

 

Ho-ly. ****.

The hose that feeds the front left strut on the W220 chassis from the front right valve block is the stupidest hose I've ever seen, requiring what looks like the removal of the front bumper to replace properly.

The hose coming from the valve block shows light signs of rusting and a little bit of leaking. The hardline hose runs so stupidly, up under the bumper, then to the top, into an expansion/larger pipe section, then with hardline tubing around and back down, back in between the bumper and the frame (necessitating bumper removal to access, all hardline tubing), to a coupler that then goes to the line that feeds the front left strut. I've retraced it three times now, this is actually how it runs.

It's showing slight rust and signs of leaking (very similar to the line that popped). I cannot replace this line. In fact, I'm unsure what to do with it. I think I'm going to leave it to break later, and if/when it does, I will fabricate a new line and find a way to fix it in vivo.

This is one of those rare times working on a Mercedes where I have to ask myself "what were they thinking". This line does not appear in any of the ABC diagrams mercedes has published. ****.

 

It looks like it's a question of removing the radiator support bracket. I have to think about doing this, there are two rivets that will need removal.

 

Hold up.


Led to this:
https://www.youcanic.com/mercedes-be...ct-connectors/

Maybe Mercedes used disconnect lines here? Here is the hose in question (the one with the yellow tag):

 

 

I just typed out a huge reply, and it went lost when firefox decided being retarded was preferable to working right.

it's fixed. details to follow whenever my rage calms down.

 

UPDATE!

Car appears to be fixed and has passed an initial test drive. While the ABC system was drained, I inspected three of the four accumulators (inserting a zip tie, it should not go through the bottom and the accumulator should not be full of fluid), they were fine.
Here's the hose that popped fixed:



The fix included the addition of swivel joints. These come with a HUGE asterisk and I do NOT recommend them if available. 1. DON'T FORGET TO TIGHTEN THEM AFTER INSTALLATION! I made this mistake.... twice, and ended up with CHF11S all over the floor. 2. Ideally they are tightened once installed, but there are no guarantees you will be able to reach them with the requisite two wrenches. 3. They widen and remove flexibility from the line The line must not touch any of the body, or other hydraulic lines.. If possible, get crimped lines, but ensure the geometry is good. The hydraulic shop I used only had these wider 3/8" ID (inner diameter) lines (the ID of the 15mm lines is 10mm), which are wider than the originals, but will likely last the life of the car. If you feel swivels will work for you, by all means go for it.

Then there is the questionable line I mentioned in post #11. I spoke with Victor at restoreyourmercedes.com (catchy!) and he made a very good point: the lines feeding the struts directly should be replaced if they are weeping. If any of the other ABC lines blow, it's not a huge issue; the ABC computer will immediately shut the valves in the valve blocks feeding the hoses to the struts, thus maintaining pressure in the struts. If one of the hoses feeding the struts blows, that strut will immediately sink to the floor and could pose a serious hazard. For this reason, any hoses feeding the struts from the valve blocks with any signs of issues (in my case corrosion and weeping) must be replaced.

Mercedes maintains the same line length (and geometry) for the left and right struts, despite the fact that the valve blocks reside on the left side of the car. This means the lines to the left struts make loop around. The aforementioned questionable ABC line feeds the left strut, thus making a failure unacceptable. Unfortunately the full line loops and winds somewhere between the bumper and radiator, making its removal AWFUL. For this reason I went ahead and attempted a fix without removing the rest of the line. I used a multitool the cut the line where I could slip a compression fitting over. This is a tried and true method in both plumbing and hydraulics. You can find information on their installation and strength here:


Here are the results:



This is looking up from the floor at the front left of the car. The top of the image corresponds to the front of the car (the front bumper is visible), the bottom the rear. The OEM mercedes hose has a 90° turn that I cut off and added my own with the new hose. At first I was only going to use the section of the OEM crimp, but adding a compression nut extended the line to such a degree, it wouldn't have fit with the geometry of the car. Here is the small section of hose I replaced:



Some additional notes: Mercedes has specific instructions for refilling a drained ABC system, follow them. I found what they wrote to be very accurate. (Document #: ar32.50-p-0021n)

They do reference a pump to manually pressurize the struts before actuating them. I didn't have that, and just had the car do its eerie jump as I the fluid came rushing back in.

Anyway, I hope all this is helpful. This was not a fun past week, and I also noticed one of the lines feeding the rear struts is showing signs of failure, so I've ordered both lines for the rear struts to have on hand and replace at my convenience. Unfortunately these lines are wedged so tight in there, repair is not possible (the added width of the fixed rubber hydraulic hoses will cause trouble).

 

One more thing,
if lines are touching or look close enough to be touching, hydraulic shops sell line wraps so they don't rub. Here the larger diameter hydraulic line caused trouble so I wrapped them in these plastic wraps at specific points. The tie straps are to theoretically keep it "in place".

 

One of the ABC lines popped again, which one remains to be seen. If it's the same one I replaced, either I ****ed up the replacement (possible), or the maybe the valve block is misbehaving and somehow sending all the pressure to that unit?

 

I strongly recommend replacing ALL the accumulators when one goes flat. You cannot determine the charge left in a unit while mounted and without the fittings and hand-powered hydraulic pump and pressure gauge. They are cheap enough. The nitrogen precharge slowly seeps through (dissolves into the rubber) and then out into the oil. There should be 25 Bar (350 psig) of gas pressure for the units to work properly and absorb shocks from valves opening and closing.

 

None of them are flat though

 

The line going to the rear accumulator failed. There is no rust, no indication of leaking, no indication of anything. The hose was replaced 3 or 4 years ago. This is bull****. The only thing I can think is that it was rubbing against the body in some capacity, but no. That should not be the case. There's no reason this line should have failed.

 

Just checked, and the accumulator it's feeding is good.

 

Looks like I'll be dealing with this myself now too. I got on the car a little hard a few blocks away from home and as soon as I got to the driveway I got the red ABC light with a trail of fluid behind me. The biggest puddle is underneath the left front end, but the whole left-side undercarriage is covered in fluid. I'll dig into it this weekend if I'm feeling motivated.

 

Time to put on your big boy hat and go through the whole system, checking for potential problem pipes, and check the accumulators while you're at it.

 

I already ordered the accumulators and other lines. I'd already planned to do a flush so I guess this forces my hand a little earlier than I had anticipated. I had just made a 140 mile round trip so luckily this happened close to home.

 

Don't forget to swap the filter. You are indeed lucky. Find the one that popped? When replacing lines, follow Mercedes' indstructions, it makes your life easy.

 

Update, replaced the rear line to the accumulator, replaced the lines feeding the R+L struts as a "while you're in there" type thing (don't want the car dropping to the ground). Also replaced the pressure relief valve block (where the pulsation damper connects) as its the only explanation I have for the failure of the rear accumulator line. Did a rodeo, the pump can't maintain pressure for the whole thing, but it's never been able to do that, even with a fresh pump swap. So far everything is good, except for an unusal clicking around the rear left wheel (not the valve block).