My 600sl rides very hard and bounchy

[600 sl maniac]

I just completed a job on the self leveling valve successfuly,stoping the leak by replacing an o ring seal.
I put back everything in its place but when I drove the car I felt that the ride was very hard and bounchy. Did I miss out somewhere?
Any help is welcomed.
thank you

[JimFreeh]

Classic case of the nitrogen spheres going bad.

You've got two, used to be around $100 each.

Jim

[600 sl maniac]

thank you Jim,
I thought of that too but my ride was quite comfy before the leak. Could it be a procedure that you have to do after fixing the leak?
I ve read somewhere that you need to re-adjust by puting weight to the rear end but I couldnt follow up exactly how this been done. Any views on this step?

[JimFreeh]

Whilst I have no experience with the R129, it's self leveling suspension is functionally the same as my W124 wagon and W126 sedan.

The "shocks" in a self leveling system do not function in the same way as a normal shock. The N2 spheres have a bladder in the sphere.Oon one side is the N2 gas, and on the other is the hydraulic fluid. The displacement of the "shock" pushes more fluid into the sphere, compressing the N2. This is your shock absorbing action. Failure of the spheres (about every 100K miles) is by the N2 leaking out and this cushion ability fails, leaving the suspension reluctant to deflect, causing the hard ride and the bunny rabbit jumping around.

I've changed 3 sets of spheres, and the trigger was the symptoms you describe each time. The system is self bleeding, and as long as the leveling valve was not disturbed (adjusted), the system was self bleeding.

If your problem has just appeared, if it were me, I'd revisit the last thing I perturbed. You could back the car onto ramps, climb under the car, and disconnect the ball joint on the rod that connects the level valve with the sway bar, and manually move it back and forth to see if the level adjusts, and that the action is smooth on the valve. It's possible the valve is restricting flow due to misadjustment or incorrect assembly, giving you the failed N2 sphere symptom.

Jim

[600 sl maniac]

Jim thank you for this one. I will let you know as soon I get around lifting the car up. By the way, how many speres do I have? How easy could be if I need to change any of them? Is there a test that can be performed in order to make sure that the N2 is gone?
appreciated again for your response

[moakesr]

The 600SL and 500SL with ADS have four spheres, two in the rear in the spare wheel compartment, and two up front, behind a cover in the front wheel arches.

Which valve did you change the O-Ring in? If you have disturbed the main ADS valve/manifold, then there is a bleed procedure.

Richard

[600 sl maniac]

Richard well received your reply. I changed the o seals on the front self leveling valve. Please describe the bleeding procedure.
thanks