lilbizilik

So, just more disappointment from the ABC system. I have an 03' S55 with 90k miles. A year ago the ABC/PS pump was replaced and 3 months ago all 4 shocks were replaced with Arnott shocks. Everything was fine for a record-breaking 3 months until, all of a sudden, I noticed a huge puddle under the front of the car after turning it off. The weird thing is that it occurred about 3-5 mins after turning the car off. When I opened the hood, everything was covered in hydraulic fluid and the ABC dipstick was loose. Just so you know, every two days I check the fluid level for the suspension and power steering; both were at appropriate levels. After the explosion of fluid, the ABC dipstick oil level was only a few mm below the engine-off level. I then decided to turn it on real quick to move it to the flat part of my driveway. No message showed up on the dash and throughout no part of this did any corner drop. I immediately drove my other car to the MB dealer to get some Pentosin 11s and a new ABC filter. I then replaced the filter and got the fluid level to the right amount. The filter element was quite dirty, but no visible pieces. I will dissect it later tonight. I drove the car for 15 mins and everything was fine - no suspension drop or leaks or weird noises. But the same damn thing happened after the car was off for a few minutes. What could be the problem? Do you guys think it might be valve blocks? The blocks havent been replaced but the car hasnt been dropping at all, not even if I dont drive it for a few days. Could the valves still be bad if the car doesnt drop?

Thanks in advance,
Ben

Shifter

There is an integrated filter in the ps reservoir. Non serviceable. I've seen it being clogged cause this but at the ps resv not the susp resv.

Not sure if that helps. GL

lilbizilik

That is good to know. But this problem is exclusively with the suspension reservoir/system.

I just did the whole top off the fluid thing and, once again, the same thing happened. I've read in other threads that they've had this problem once after doing a rodeo, but never more than once.

Welwynnick

Never heard of this before. Its hard to imgine how there's enough fluid in the struts to overflow the reservoir even if all the valve blocks collapsed.

My thought is that there must be air in the system that expands when the pressure source is dropped, and forces all the fluid out.

Nick

lilbizilik

Welwynnick, that sounds right. I finally got to stop overflowing last night up until an hour ago. Witnessed it first hand and saw the fluid boiling. Im going to flush the system and manually bleed it tonight. If that doesnt work then I guess its a trip to the stealership for a rodeo.

w4sim

Did you manage to sort this?

And wheres the ABC filter that can be changed? Im looking at changing the pulsation damper on mine and was thinking of replacing the ABC filter aswell, but no idea where it is or how to do it?

Thanks.

lilbizilik

Yup, somehow got it fixed. I did the bleed technique of pressing the raise/lower button 15 times and then turned the car off, waited a few minutes and then turned it back on and somehow that got the air out. ABC fluid temp hasnt gone above 142 degrees Fahrenheit since then.

The ABC filter is located in the fluid reservoir and is attached to the return line cap. So you know where the rubber dipstick thing is on the reservoir? To the left of that is the return line and its attached to the reservoir by that cap. Unscrew the cap and pull up on the hose, which will also pull the filter out so you should be able to see it easily. Taking off the filter is a bit tricky. Also, make sure you wait like 10-15 mins after you turn the car off to do this because fluid might still be draining into the tank. Get the filter all of the way out of the tank and you should see the spring at the bottom of the filter. The setup for this is really weird... the spring has a metal rod that goes through the filter to top, where the return line is. At the end of the rod is a hook, and is hooked on to a little hoop on the return line cap. By compressing the spring an inch or so, you push the hook up and uncouples it from the hoop. While you're still compressing the spring, tilt the filter and try to move it which ever way will end up moving the hook away from the hoop.

I really wish I could explain this better. If you need better instructions, let me know and I will make a video or post pictures of it.

mrbenzes

Mine (2005 S55) did the same thing one time right after I flushed the ABC fluid...it shot out a decent amount of fluid after I shut everything down....the car was a bit low so I restarted it and brought it up to the "High" level, and then back to normal. I topped off the fluid and it hasnt done it since...been about a year now without any issues.
Mike