Front ABC struts sagging
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Joined: May 2021
Posts: 554
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From: Netherlands
CL 600 '00 5.8L V12
Front ABC struts sagging
As part of ABC maintenance, I opted to do an front valve block clean (replace all the O-rings and clean out the dirt)
When re-installing the valve block I switched the wires of the regulating valves around, obviously without me noticing it.
When I started the car, to flush the system, the struts wouldn't come up, until a certain point where one side of the car shot into the air.
Eventually that one lowered a bit and the other strut shot up in the air.
The bleeding was particularly fast as I'd to refill the reservoir a lot more often than on the videos I saw.
From that day on, the front suspsension sags. It takes around 3 days to fully sag, but I do notice that the front of the car rises a little, when I left it parked for about 8 hours.
My imagination pointed me to the possible cause of the issue being that the o-rings of the check valves where blown out, due to the valves being in a posision that they should not be in (regulating valve fully open and check valve fully closed)
I replaced all the o-rings of the solenoids on the front valve block (and made sure to put the wires in the right locations this time), but the issue is still there.
I do not see any oil leaks around the struts or the hoses.
There was an mini leak comming from the accumulator line when I reinstalled the valve block for the second time, but I've fixed that one.
So the ultimate question still remains;
What are the odds that I blew out seal(s) in both the suspension struts itself?
ABC Maintenance history:
1: Replaced both accumulators, replaced front valve block o-rings, flushed the ABC system (inc. new filter)
2: Replaced the front valve block o-rings (to fix the sagging)
When re-installing the valve block I switched the wires of the regulating valves around, obviously without me noticing it.
When I started the car, to flush the system, the struts wouldn't come up, until a certain point where one side of the car shot into the air.
Eventually that one lowered a bit and the other strut shot up in the air.
The bleeding was particularly fast as I'd to refill the reservoir a lot more often than on the videos I saw.
From that day on, the front suspsension sags. It takes around 3 days to fully sag, but I do notice that the front of the car rises a little, when I left it parked for about 8 hours.
My imagination pointed me to the possible cause of the issue being that the o-rings of the check valves where blown out, due to the valves being in a posision that they should not be in (regulating valve fully open and check valve fully closed)
I replaced all the o-rings of the solenoids on the front valve block (and made sure to put the wires in the right locations this time), but the issue is still there.
I do not see any oil leaks around the struts or the hoses.
There was an mini leak comming from the accumulator line when I reinstalled the valve block for the second time, but I've fixed that one.
So the ultimate question still remains;
What are the odds that I blew out seal(s) in both the suspension struts itself?
ABC Maintenance history:
1: Replaced both accumulators, replaced front valve block o-rings, flushed the ABC system (inc. new filter)
2: Replaced the front valve block o-rings (to fix the sagging)
