The only thing that can cause the rear to raise and lower like that is the SLS valve. The pump supplies the pressure to the valve but it's not going to change the ride height. Are you sure you got it put back together correctly and/or non of the o-rings got damaged while putting them in.

I reworked the SLS Valve O-ring PDF here it is again.
http://oregonstate.edu/~lindgrea/DIY/PDFs/w123_sls_valve_seal_inst.pdf

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I feel very confident that the SLS valve went back together perfectly no damaged o rings etc - I may change accumulators and see what happens as they are quite old and original -

Accumulators generally cause bouncy or harsh ride. They aren't going to cause the rear to lift and lower randomly. When they go bad the big rubber diaphragm inside tears and the whole sphere fills with fluid. Ride height is only affected by the pump and the valve. I still suspect the valve. You might have a valve that isn't working right.

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I am going to buy another valve and replace seals as I had problems initially and will replace accumulators anyway as they appear to be original. I was told by an Indie Mercedes shop that they have never had any luck rebuilding SLS valves but scores of people on this site report no such problems . . . probably wanted to sell me a new valve!

Hi
Do you suppose you might have an adjustment problem with the pull rod that connects the SLS Valve lever to the sway bar lever? I don't know this - its just a thought.
Joseph

Thats what I would look for....

Summit in the linkage to the valve from the anti-roll bar....

On my Citroen Xantia (Same basic idea, fully hydopneumatic suspension) the valve is connected by a small plastic link that used to pop off its ball-joints...

The back end of the car would sink or rise depending on where/what position the valve had come adrift from the linkage....
VERY common fault on Xantias....

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http://i190.photobucket.com/albums/z...0TDnoplate.jpg

Alastair AKA H.C.II South Wales, U.K. based member

W123, 1985 300TD Wagon, 256K,
-Most recent M.B. purchase, Cost-a-plenty, Gulps BioDiesel extravagantly, and I love it like an old dog.

W114, 1975 280E Custard Yellow,
-Great above decks needs chassis welding--Really will do it this year....

I hadn't thought about the rod from the valve to the sway bar. Definetly check that before buying a new valve.

I've had a couple shops tell me the same thing about rebuilding the valves. A lot of shops don't rebuild parts because it's not worth the money to do it. It's cheaper and easier for a shop to slap in a new part, rather than deal with the headache of rebuilding certain parts.

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