How to replace air suspension valve block?

[ChrisHGTV]

Hello all.

I have a 2011 E250 S212 with the dreaded rear suspension sinking. It had one bellows replaced under warranty just over a year ago as the garage couldn’t find a leak but that side (left) seemed to be dropping more, but actually not that much. In hindsight not actually sure that cured it. Recently it’s been dropping more on both sides and consistently, ie same amount each side. A leak was found in the compressor body so compressor replaced but it’s still dropping. So thinking next cheapest thing to try is the valve block. Thinking it could be allowing pressure to leak back through to the compressor and then out via the relief valve?

so have ordered one as quite cheap (from meissener), but to fit do you trim a short section of the pipe and push into the connection, or do you remove the brass fitting, push in the pipe, then re-attach to the valve body? I can’t seem to find a “how to”.

cheers

 

[steveq]

I havent ever replaced the valve block so can't help you there.
I would be looking for leaks in the pipe work and would also be suspicious of the other air suspension unit that wasn't replaced.

 

[ChrisHGTV]

Thanks Steve, yes two specialist garages have actually looked at it so far and it’s still leaking somewhere. I hope it’s the valve block otherwise the next thing to try will be the remainder of the pipe work and/or the other air bag. At which point the whole system would have been replaced! The thing that leads me to think it’s not air bag related is that it drops on both sides the same amount. If it is a bag leaking I guess that must mean the valve block is also leaking to impact the other side. I can’t believe the replaced air bag would be leaking after just a year or so, it was a Merc one.

 

[liapants]

Hi can anyone help I have a E270 saloon I have a bang noise on the n/S back when go over a small pot hole garage told me it’s the airbag is it hard to change and can it be done on stands the car is all level just annoying with the noise

 

[ChrisHGTV]

Hi can anyone help I have a E270 saloon I have a bang noise on the n/S back when go over a small pot hole garage told me it’s the airbag is it hard to change and can it be done on stands the car is all level just annoying with the noise

If the car is still level it doesn’t sound like the airbag to be honest as that would drop the car right down on that side. If it’s a knocking noise it could be the shock top mount broken as I’ve seen on the forum sometimes these can fail. I guess if you jack up that side of the car you could give the top of the shock a wiggle to see if it’s loose. I don’t think you can really see the mount without removing the shock, not that I’ve purposefully tried to see it!

 

[liapants]

If the car is still level it doesn’t sound like the airbag to be honest as that would drop the car right down on that side. If it’s a knocking noise it could be the shock top mount broken as I’ve seen on the forum sometimes these can fail. I guess if you jack up that side of the car you could give the top of the shock a wiggle to see if it’s loose. I don’t think you can really see the mount without removing the shock, not that I’ve purposefully tried to see it!

Thank you very much for that I my self thought is was the gas strut I will try that

 

[ChrisHGTV]

If the car is still level it doesn’t sound like the airbag to be honest as that would drop the car right down on that side. If it’s a knocking noise it could be the shock top mount broken as I’ve seen on the forum sometimes these can fail. I guess if you jack up that side of the car you could give the top of the shock a wiggle to see if it’s loose. I don’t think you can really see the mount without removing the shock, not that I’ve purposefully tried to see it!

I was playing around with mine today and you can actually see the shock top mount from inside the wheel arch if you take the wheel off.

 

[shp3r1uk]

Hello all.

I have a 2011 E250 S212 with the dreaded rear suspension sinking. It had one bellows replaced under warranty just over a year ago as the garage couldn’t find a leak but that side (left) seemed to be dropping more, but actually not that much. In hindsight not actually sure that cured it. Recently it’s been dropping more on both sides and consistently, ie same amount each side. A leak was found in the compressor body so compressor replaced but it’s still dropping. So thinking next cheapest thing to try is the valve block. Thinking it could be allowing pressure to leak back through to the compressor and then out via the relief valve?

so have ordered one as quite cheap (from meissener), but to fit do you trim a short section of the pipe and push into the connection, or do you remove the brass fitting, push in the pipe, then re-attach to the valve body? I can’t seem to find a “how to”.

cheers

Hi there,

Just wondering how you solved the issue in the end. I have the same problem on my CLS Shooting Brake. In my case, the driver's side was always lower. I had it a Mercedes Independent garage, they ran full diagnostics and checked the system (apart from the actual bags). Found a hole on the driver's side pipe and replaced it. Charged £220 for it. When I got up the next morning the back was sunk right down. When driving seems to be levelled up now, but still sinks overnight. Getting it to a different Mercedes Independent garage beginning of next month and will see.

 

[zipdip]

Well it is rare for the valve block to be the problem,but hey it is worth a try,I would look at the rear axle air distribution block it is this that will supply the air to the rear airmatic,but it will not hurt to get out the soapy water and check for leaks on the valve block and the distribution block best of luck.

 

[ChrisHGTV]

Hi there,

Just wondering how you solved the issue in the end. I have the same problem on my CLS Shooting Brake. In my case, the driver's side was always lower. I had it a Mercedes Independent garage, they ran full diagnostics and checked the system (apart from the actual bags). Found a hole on the driver's side pipe and replaced it. Charged £220 for it. When I got up the next morning the back was sunk right down. When driving seems to be levelled up now, but still sinks overnight. Getting it to a different Mercedes Independent garage beginning of next month and will see.

Well in the end I had all the lines replaced as well as the remaining air bag. I actually think it was the lines, as when I was investigating it more i managed to make the leak worse, and it was clear it was one of the lines. I had the remaining air bag replaced anyway as I had already ordered it in anticipation! The line had developed a leak at a point next to where there had been a repair before. The official air line repair section includes a brass joining piece. And as The lines from the valve block run side by side, where this brass joiner is on one of the lines it had obviously pushed the other line more in contact with the bodywork. And I guess a bit of rubbing had caused a leak. In the end on mine I basically replaced everything - air bags, lines, valve block and compressor. So not cheap but it now doesn’t drop at all after 2 weeks. In hindsight and seeing the condition of the lines I would change those out first As they’re relatively cheap.