eFifty5AMG

Just installed a pair of Arnott A-2725 on my ‘04 E55 because the rear factory springs were sagging overnight. Now that the Arnott air springs are installed, the leak is much worse-the back will drop all the way down throughout the night with the right side being a bit worse. I tried soap & water but did not see any bubbles. Nothing obvious showing at the rear block either. Not hearing any hissing. Did not use the new Voss fittings, but replaced the o-rings at the connection. No codes showing in star & I also performed the pneumatic test for the compressor & it reaches 14 bar in a few seconds.
So I ordered a new valve block for the front from FCP & hopefully it’ll be here soon & solve my issues. I tried spraying the valve block with soap & water but still no bubbles appearing; thinking maybe it’s an internal leak.

When I first inflated the bags, I partially lowered it down from my lift & inflated to 2 bar, then 10 seconds as star shows. I’ve driven a couple hours on it & I get no “visit workshop” when driving, but I don’t feel comfortable driving around & possibly overworking the compressor.

Am I missing something?
Side note, my rear springs are not red (mfg 2017) should they be? The back right also sits about 1 finger lower than the back left, normal?

MACEDON

If you're not detecting a leak then could the issue be elsewhere? Does the system need recalibrating?

Mine are red, but I think that's because I think I have the kit for an E500 not E55.

eFifty5AMG

That’s what was making me think valve block..possibly an internal leak that couldn’t be detected via the simple leak tests. I thought the Arnotts didn’t need any Star adjustments following the install. What’s the process for recalibration?

GrumpyDad

Why did you not use the Arnott fittings? I have tried to re-use the old fittings on other vehicles. Usually leak. Look very close at whatever fittings you used. Spray and watch very closely with the weight of vehicle on the springs. 2 months ago I installed 2 Arnott rear bags on a GLS 500. Dropped overnight. Finally found the fittings / o-rings were not installed properly out of the box. Removed them, lubricated the exterior o-ring and re-installed. All good now.

eFifty5AMG

Honestly, I couldn’t get figure out how to get them off. It’s just a compression fitting, correct? I tried pushing around that lip & was afraid I’d snap a line trying too hard so I decided to swap the o-rings instead. I looked very very closely at the fittings with the spray test & didn’t see anything, but that’s not to say they aren’t still the culprit. Any suggestions on how to remove them? I left the car sitting on my lift with the tires on the ground but not much weight & the rears still sagged when I lowered it this morning. I will try the new fittings possibly tonight & see if that changes anything.

GrumpyDad

It's actually very easy, but I too didn't understand it until I spoke to Arnott. After unscrewing the original fitting out of the spring, slide it up the air line. Remove the exposed compression ferrule from the line (just spread it open, it is split and will probably break). Install the Arnott fitting into spring - lube the O-ring and tighten carefully, but tight. Pull out the plastic stem in the new fitting - it keeps the new ferrule aligned while installing the fitting. Lightly lube the air line (First inspect the line for excessive grooves from the old ferrule, minor grooves are fine) and push it into the new fitting. It will take some effort and push the line in as straight as possible to prevent it from bending or kinking. There should be a paint mark on the air line. Push it in as far as possible - the paint mark should end up just short of the top edge of the fitting. Get a reference from the old fitting or even one of the front fittings under the hood. When completed, fill system and inspect fittings very closely. Majority of the leaks occur there. Good Luck!

eFifty5AMG

Appreciate the detailed response! I’ll give it a shot tonight & report back later.

GrumpyDad

I'm a tech in Tempe AZ. Would be happy to help you any way I can. Let me know.

eFifty5AMG

No luck. Swapped out the fittings last night (super easy just like you said) but this morning it was still aired out. Do you think it’s the correct move to tackle the valve block next?

GrumpyDad

I have never replaced the valve assembly on an W211 Airmatic System. The rear bags (and front struts) have a locking valve (the electrical connector on the bag) which closes and maintains air pressure when the car is parked and shut off. Other Airmatic systems only have the air line attached to the bag and all pressure control and locking are done at the valve assembly. My scan tool allows me to perform several isolation tests which aid in locating leaks and malfunctions. You may have defective or damaged spring? I replaced my rear bags with Arnotts several months ago for sagging issues (worse when cold) and have had no issues since. You mentioned you had the "black" ones (as opposed to the "red" ones). The black ones are the most recent ones and what I used. Good Luck

eFifty5AMG

Ended up being a defective Arnott air spring.

forcefed4door

What a royal pain man. Glad you figured it out though.

tw2

That's pretty unlucky. Glad it's sorted. Did they say anything about it?

eFifty5AMG

Yeah, it totally sucked. Took me a couple weeks after work trying to find another leak that didn't exist, but I learned a few things in the process so I can't complain too much. I didn't really get into it, just returned the bag & bought a new one. Thankfully I didn't install the main valve block yet so I can get some $ back for that.

new55

so it was the right side that had the leak but both sides sagged ? how do you determine which side is the offending bag ?

eFifty5AMG

Yes, I used the service jack under the back right to hold the car level throughout the night & the car would remain level. When I lowered it back down off the jack, there would be no air left in the back right air spring. If I left it with no jack underneath, both sides would drop, but the back right would be slammed.