Self Levelling air suspension problems

[Andymerc UFO]

EmilysDad, should probably have gone to A+E but i spent too much time in those places as a youngster (no computers back then) so i’ve Just been suffering in silence (mostly) Besides I don’t think they can put a pot or sling on a pelvic injury.

Davec52, I know what you mean about those older compressors degrading. However, I have recently installed a new one so we’re definitely good there. I heard the hiss of air at the back wheel so it’s either a leak there or for some reason the system (height sensor) is telling the bleed valve (if there is one) to release air. This is why i was trying to get some info and diagrams of the whole system on just the ‘self leveling’ suspension.
The internet has very little on the subject.

 

[DaveC52]

Davec52, I know what you mean about those older compressors degrading. However, I have recently installed a new one so we’re definitely good there. I heard the hiss of air at the back wheel so it’s either a leak there or for some reason the system (height sensor) is telling the bleed valve (if there is one) to release air. This is why i was trying to get some info and diagrams of the whole system on just the ‘self leveling’ suspension.
The internet has very little on the subject.

I have had a quick look for a diagram of the self levelling which I had and have probably deleted can't remember where it came from could be the Haynes manual or the Merc WIS if it turns up I will post it.

I was considering converting to coil springs if anything went wrong with the air suspension a lot cheaper than two replacement air bags, also I was told that Mercedes do refurbished air bags considerably cheaper than new ones don't know if this is correct or bulls**t but worth checking out if it is an air bag.

 

[LostKiwi]

I have a technical manual on airmatic.

See if you can download it here:
https://www.dropbox.com/sh/z2p958igwq3qq1s/AABEv4ozRvWkUEcdq-z85aAfa?dl=0

 

[DaveC52]

I have just spent a couple of hours on my WIS after putting the T211's chassis number in, which should come up as an Avantegarde Estate with rear only self levelling suspension it tells me that my suspension is Airmatic tried everything to find a diagram to no avail plenty showing Airmatics but one thing I have found out is that Mercedes do actually sell reconditioned air bags or bellows as they call them.
Probably find that the Haynes manual has a very good diagram I haven't got one though and sorry I couldn't be of any help

 

[V6Matty]

The Airmatic option isn’t very dissimilar to SLS, additional tank and valve block and bags at the front as well, few extra bits of electrickery and your done (okay that’s massively oversimplification)

 

[Conor]

I have just spent a couple of hours on my WIS after putting the T211's chassis number in, which should come up as an Avantegarde Estate with rear only self levelling suspension it tells me that my suspension is Airmatic tried everything to find a diagram to no avail plenty showing Airmatics but one thing I have found out is that Mercedes do actually sell reconditioned air bags or bellows as they call them.
Probably find that the Haynes manual has a very good diagram I haven't got one though and sorry I couldn't be of any help

I found something similar myself for my S212. I just couldn't find any diagrams for my suspension config at all, it's actually very frustrating.

(That was during an attempt to find you diagrams, as promised, but to no avail)

 

[LostKiwi]

I found something similar myself for my S212. I just couldn't find any diagrams for my suspension config at all, it's actually very frustrating.

(That was during an attempt to find you diagrams, as promised, but to no avail)

Did you download the document I linked to? Everything you need to know should be in there.

 

[Conor]

Did you download the document I linked to? Everything you need to know should be in there.

Yes I had a quick scan - it looks like a rip straight out of wis. I still couldn't find a diagram depicting my exact setup though, which is a bit annoying.

It's mainly annoying as I embark on other jobs, I wonder what the differences will be.

 

[LostKiwi]

The main differences will be component locations. The fundamental design will be broadly the same.

 

[malcolm E53 AMG]

The airmatic pump on the 212 is situated under the boot rear of the back axle accessed by dropping the splash guard and the manifold sits with it. The relay sits in the near side rear wheel well (there is an access cut in the carpet just below the rear lights). The airbags (bellows in MB parlance) sit just inwards of each rear wheel and pipe work and levelling sensor around the rear axle to suit so all in all a very compact system

 

[pgh13]

Had a similar problem a couple of years ago with a W211..... Sometimes down on one side and eventually had replaced one airbag and the compressor. In researching discovered a couple of companies that manufacture replacement parts cheaper than Merc. One such company is Arnott and if you look on YouT***, they have some videos on replacing various suspension components.

 

[Conor]

Yes, Aerosus is another.

There has been positive threads on here about Aerosus. I replace both sides with Aerosus a couple weeks ago and took many pictures, I plan on doing a write up.

 

[Simon Barry]

Had a similar problem a couple of years ago with a W211..... Sometimes down on one side and eventually had replaced one airbag and the compressor. In researching discovered a couple of companies that manufacture replacement parts cheaper than Merc. One such company is Arnott and if you look on YouT***, they have some videos on replacing various suspension components.

I ordered a compressor from Arnott as a spare, they lost it on delivery on the continent, it took me a long time to get my money back !

 

[Andymerc UFO]

Finally up for thinking again about doing some repairs on the Merc when the other car (bmw) decides to have a leak on the brake pipes! As a result i used the Merc to make a short journey of 5 miles to my shop and back and as i was parking up at home there was a loud bang from the rear and the car dropped. So it’s definitely new bags required now. Anyone heard of this happening before? It would have been a real pain if it had happened 5 minutes earlier. I’m guessing it could have happened because the nearside was up higher than the offside possibly due to a levelling sensor problem before the bang... (I think it was the nearside that exploded)

 

[Andymerc UFO]

Wow! It’s taken me a while but i finally got started on these airbags.

I got fed up seeing the old girl sitting in the driveway looking sad so i got her up on axle stands today and had a play. I managed to get the first one off without too much fuss. It was the one that had exploded. Putting the new one in was a bit more of a farce. I got it positioned easily enough but the bottom of the bag wouldn’t fit in the control arm. It was a little bit wider than the original. Eventually after much swearing i tried my ball joint splitter and managed to prise the lower control arms open enough to locate the bag and get the bolt through. success. Then i tried to do the other side. Unfortunately after undoing all the bolts etc and disconnecting the air line and cable, i couldn’t get any further because the air bag was still pressurised! Since it was getting dark and very cold (-0.5) i put the bits back on and decided i was going to finish the job another time. However, i thought i’d Set the airbags for now by starting the car up without dropping the car first, due to the new airbag being “un-pressurised” and not reaching the locating pin at the top end. Nothing happened. the compressor didn’t fire up at all. So i had to leave the car up on stands for now.
I would appreciate any info from anyone as to how i should proceed.
My thoughts are to deflate the old airbag with a football valve (or small nail)? Has anyone done this?
Hopefully the compressor issue is just because the system thinks it’s ok due to the full bag and no weight on the rear end.

 

[Conor]

Wow! It’s taken me a while but i finally got started on these airbags.

I got fed up seeing the old girl sitting in the driveway looking sad so i got her up on axle stands today and had a play. I managed to get the first one off without too much fuss. It was the one that had exploded. Putting the new one in was a bit more of a farce. I got it positioned easily enough but the bottom of the bag wouldn’t fit in the control arm. It was a little bit wider than the original. Eventually after much swearing i tried my ball joint splitter and managed to prise the lower control arms open enough to locate the bag and get the bolt through. success. Then i tried to do the other side. Unfortunately after undoing all the bolts etc and disconnecting the air line and cable, i couldn’t get any further because the air bag was still pressurised! Since it was getting dark and very cold (-0.5) i put the bits back on and decided i was going to finish the job another time. However, i thought i’d Set the airbags for now by starting the car up without dropping the car first, due to the new airbag being “un-pressurised” and not reaching the locating pin at the top end. Nothing happened. the compressor didn’t fire up at all. So i had to leave the car up on stands for now.
I would appreciate any info from anyone as to how i should proceed.
My thoughts are to deflate the old airbag with a football valve (or small nail)? Has anyone done this?
Hopefully the compressor issue is just because the system thinks it’s ok due to the full bag and no weight on the rear end.

Hi, good work.

The cold is a real bugger.. I have learned my lesson lately too, that any non emergency work should be done during the summer months if possible.

I think the reason the compressor didn't engage was because, like you say the car was up. There is a level sensor on each side, which can be adjusted to trick the car if you wanted.

When I was doing mine, one of the bags was fully like you mention. I did a pretty risky thing.. I got a blade and basically started swiping at the compressed air bag until it popped. It felt pretty risky and stupid, but was very effective. I was wearing gloves and I manoeuvred myself to be away from the bag.

Others have mentioned using a spanner to very slowly open the nut that holds the air line at the top of the bag. And some have also just drilled into the plastic above the rubber area, which is similar to what I did really.

Hope that helps.

 

[Andymerc UFO]

Hi, yes i did consider attacking the bag with a blade or drill but decided against when i read that there is about 34bar (ish) in them! I had already taken the nut off and removed the pipe thinking that would release the pressure. But no.