ABC Pump / High Pressure Hydraulic Line Replacement DIY

[ch33sehead]

Originally Posted by Sendmedem 2001 S600 - I drove out of my driveway and saw a puff of what looked like smoke come from the front left wheel well. A few seconds later the car warned me in red "Active Body Control.. Drive Carefully" I stopped the car and saw a dripping leak all over the front left, spash from the tire in the wheel well and under the hood there was a little puddle coming from seemed like under the headlamp and creeping to the middle of the rail I am about to take some things off/apart to see what happened but If anyone knows what this could be or has had the problem please let me know. Thanks in advance. PS the DIY pics are no longer good if someone can repost them or has some of their own.. In front left near headlight there is a valve block and accumulator. No point in speculating, just get stuff off and look at it.

To remove this ad, register today or login if you already are registered!

[steadystud]

Originally Posted by ch33sehead

Sorry but that doesn't answer the question. When you take the belt, do you still hear the groaning or does the groaning stop?

The groaning stops...and the car is as smooth as ever... Please email me at thepro1973@yahoo.com and I will send you my number. We can talk there. Appreciate any help sir. I know we spoke before.

[Sendmedem]

I found these diagrams that might help someone in the future when ordering parts from the stealership. I wrote down the mercedes picture number so when people are calling they have reference to what they are talking about.

This is from 2001 S600 - ABC hydraulic system diagrams, but I'm sure other classes have the same system installed.

[ch33sehead]

I emailed you back, you should have my number and/or email.

[driveability]

The noise could be the new pump, I've herd bad pumps (they work fine but make a growing noise) and the pattern of the noise is not linear. Most of the time it matches the engine speed vs noise but the pressure build up makes the noise seem to change pitch often. If it absolutely mirrors the engine rpm then maybe it not the ABC pump if it does as described above my moneys on the pump. Was it new ? rebuilt or what ?

[steadystud]

Originally Posted by driveability

The noise could be the new pump, I've herd bad pumps (they work fine but make a growing noise) and the pattern of the noise is not linear. Most of the time it matches the engine speed vs noise but the pressure build up makes the noise seem to change pitch often. If it absolutely mirrors the engine rpm then maybe it not the ABC pump if it does as described above my moneys on the pump. Was it new ? rebuilt or what ?

Hi Driveability,

Sorry I just saw this and you have some very good suggestions. It is a new ABC pump and not a rebuilt one. I took it to a number of technicians and got different opinions which they were kinda sure of. Go figure..!!! one said the transmission needed to be replaced as the torque converter, the bushings and the front pump was busted. The transmission people AAMCO said there was no issue with the transmission at all, my usual mechanic said there was a transmission issue, not the issue I guess. Today I have given it to another garage who does only Mercedes and BMW's and they have (not 100% though) noted it down to the Accumulator. They are pretty sure of it and have told me it will have to be done through process of elimination. I finally gave in and asked them to do it. another 400 USD .... at least it is better than 6,000 USD to replace transmission !!!!! Waiting to see what happens next.

[driveability]

Originally Posted by steadystud

Hi Driveability,

Sorry I just saw this and you have some very good suggestions. It is a new ABC pump and not a rebuilt one. I took it to a number of technicians and got different opinions which they were kinda sure of. Go figure..!!! one said the transmission needed to be replaced as the torque converter, the bushings and the front pump was busted. The transmission people AAMCO said there was no issue with the transmission at all, my usual mechanic said there was a transmission issue, not the issue I guess. Today I have given it to another garage who does only Mercedes and BMW's and they have (not 100% though) noted it down to the Accumulator. They are pretty sure of it and have told me it will have to be done through process of elimination. I finally gave in and asked them to do it. another 400 USD .... at least it is better than 6,000 USD to replace transmission !!!!! Waiting to see what happens next.

I guess the noise could sound like a torque converter to some, hard to see the converter making the same noise in P as D Hummmm . A wine type of noise is hard to isolate with one drive belt. But removing the belt would isolate it from the transmission for sure !
I did replace my line but didn't replace the pump and my pump is making a wine noise (will replace the pump this month). My pump noise is constant but does change when rpm drops quickly because the pressure I guess builds up a bit then bleeds off. Much like a turbo without a large enough blow off valve.
I look at the accumulator as a fluid shock dampener. How a wine could be created is out of my pay grade ? Maybe the block its connected to but I guess we will just have to see when your car is completed. To me the noise I have is just like a power-steering wine in sound and location. I can't here the noise I have under the hood only in the car on the driver side. Looking forward to hearing back from ya when your car is done.
John St John

[steadystud]

John,

You described it very methodically and you are absolutely right. I cannot hear it when my head is under the hood but only inside the car. Replacing the accumulator is just being done to implement the process of elimination. Hopefully I don't have all parts replaced under the hood as that would make me the biggest idiot around and put a smile on every technicians face around here every time I enter a garage !!! If that does not work then it is surely the new pump that is making that noise. I just replaced the engine mounts last 2 seeks ago and one of them (left) is already broken. I will have to get it back to the place when I replaced it. What a bother !!!! What is your email?? please email me with your contact at thepro1973@yahoo.com.

[steadystud]

Finallly the humming /groaning noise went away after I changed the Accumulator !!!! Great to drive the car with its original driveability !!!!!!! Thanks all.....especialy John St John..

[Cami1126!]

Hi,

I have 2005 S600. This car is driving me crazy. First the left side lowered then the right along with fluid leaking from the left side. I think it is a hose from what ive read and been told. Now the car wont even start. Any idea????