SL/R230: DIY ABC valve block rebuild?
Thread Starter
Senior Member
Joined: Feb 2009
Posts: 396
Likes: 21
SL63, GTR
DIY ABC valve block rebuild?
The passenger's side front suspension starts to sag after sitting for 4-5 days. Once the car is started and the suspension adjustment button is pressed, the ride height returns to normal and all is well.
I've already flushed/rodeo the system with fresh fluid and changed the filter but it did not solve the issue. From what I've read, it appears to be caused by the rubber o-rings deteriorating in the ABC valve blocks. All four struts and tandem pump are dry with no visible fluid leaks. Also, the fluid level in the reservoirs remain full.
Locating and removing the front/rear valve block doesn't appear to be a big job and they seem to be pretty easy to access. Are there any special tools/tricks/tips for replacing the o-rings that I should be aware of ahead of time?
I found these 3 o-ring kits listed below on eBay. Which kit is best for the 03 SL55 and has anyone ever used this vendor?
http://www.ebay.com/itm/Mercedes-ABC...9X5uz4&vxp=mtr
http://www.ebay.com/itm/152254742106?redirect=mobile
http://www.ebay.com/itm/Mercedes-ABC...NYL~eX&vxp=mtr
I've already flushed/rodeo the system with fresh fluid and changed the filter but it did not solve the issue. From what I've read, it appears to be caused by the rubber o-rings deteriorating in the ABC valve blocks. All four struts and tandem pump are dry with no visible fluid leaks. Also, the fluid level in the reservoirs remain full.
Locating and removing the front/rear valve block doesn't appear to be a big job and they seem to be pretty easy to access. Are there any special tools/tricks/tips for replacing the o-rings that I should be aware of ahead of time?
I found these 3 o-ring kits listed below on eBay. Which kit is best for the 03 SL55 and has anyone ever used this vendor?
http://www.ebay.com/itm/Mercedes-ABC...9X5uz4&vxp=mtr
http://www.ebay.com/itm/152254742106?redirect=mobile
http://www.ebay.com/itm/Mercedes-ABC...NYL~eX&vxp=mtr
Super Member
Joined: Jul 2010
Posts: 955
Likes: 127
From: Kansas
2003 E55, 2003 SL55, 2014 CLS63, 2018 q50 Redsport, 1968 Camaro SS, 1999 Trans am Firehawk
get a small hook to remove the old o rings. be extra careful to put the hoses back on the block correctly as well as on the distribution block on top of the valve block. I accidentally swapped the pressure and return line hoses on the distribution block (they look like they should go back on the exact opposite way you would think) and it ruined a lot of stuff before I figured out that was the problem.
Senior Member
Joined: Jul 2008
Posts: 436
Likes: 64
From: Dartmouth, MA
1967 250SE, 2022 GLC300 2023 EQB300, 2018 AMG GT
Each pair of solenoids are locked in place and to each other with a clip that will break (visible on your ebay pictures). Try and slide it out as opposed to unclip it. You will not find that clip to purchase and I had to improvise something that I am not too proud (well, it lasted 7 years). All the kits are the same, nitrile may not be the best out there but it's good. I would use the first option, the complete kit because it has the back-up rings as well. Somewhere in these forums there is a link to a detailed DIY from Germany (in german) with lots of pictures.
