The valve, accumulators, and struts are probably fine, but the pump may not be. It runs no matter what when the engine is running, so it may be toast. But I'd get some mineral oil and fill the system and see what happens. The system is self bleeding, so you just fill the reservoir and start the car and keep filling it untill it maintains between the marks on the res. Run it for a while. And keep any eye on the fluid and watch what the rearend is doing. If you get no raising at all then the pump is not doing it's job anymore.

SLS removal/install proceedure
 

Great post and info!

I am looking for the proper removal/install proceedure for the SLS pump on a 1988 560SEC. I have the repair kit already. I could probably just wing it but would rather it were done by the book.

Does anyone have some thoughts? Thanks!

David

I'm not familiar with that engine, but I'm sure someone here with the 126 FSM could post the pdf for you.

Thanks....I will start a new thread with the same question.

Thats a wise idea, you'll likely get more responses that way. Welcome to the forum by the way!

My experience with SLS
 

Purchased an '82 euro td wagon with sagging rear - pump was replaced at some point but reservoir dry! I filled system and had some results but then noticed accumulators were shot, replaced those and voila! Also replaced SLS valve with used valve and linkage arm and adjusted to neutral position. I then measured center of wheel emblem to fender lip and noticed slow settling overnight but as I drove car, it seemed to improve. I added a seal conditioner (non petrol based) to swell any dry seals and so far, things look great! I am not a big fan of "mechanic in a bottle" but I have had several successes in the past and thought I would give this a try. I will most likely flush and refill in a few more months as fluid is over a year old and I want to see if I can maintain cleaner looking fluid as a result of a better sealed system. SLS is fairly simply but I can understand why it people run from it as components are expensive. One member sells SLS valve reseal kit with great instructions - my struts appear to be in great shape and ride is wonderful versus the drive home when I first purchased this wagon -my experience, thanks

Possible to clamp off flex lines near the struts...?
 

Hey Biodiesel300TD,

Thanks for the advice. There aren't any external leaks and the system did raise the rear end. I'm fully expecting, however, that the system is probably leaking hydraulic fluid into the crankcase oil. (This would explain the previous

I'd love to sacrifice the self-levelling and just maintain pressure in the struts and/or accumulators. Anyone ever heard of this working or have ideas about methodology?

Finally, is the addition of the hyrdraulic fluid harming the lubrication qualities of my engine oil?

(79 300 td)

Thanks,

Brad

Here is a thread where we were talking about doing away with the pump and just sealing the system up. No real definete answers but some ideas.
http://www.peachparts.com/shopforum/diesel-discussion/292649-sls-without-pump.html

Also, the valve can leak internally allowing the rear to sag over time, and you'll never see a drop of fluid. So if you are seeing sagging it could be do to an internal leak. But since your res was empty it's likely going into the motor oil. I don't know the specifics of hydraulic fluid, but it is most likely not a good lubricant. Keep an eye on your fluid and see if your loosing any.

Is it the same pump as used on the 190E 16? If so I have a used one.

It is mentioned above that the system self bleeds. Most of this talk is about the W123. Does the W124 also bleed like this? If the bleeding process is automatic with system operation, what is the bleeder on the top of the SLS valve for?

I just replaced my accumulators and am looking for what else I need to do to get the system functional.

That bleed fitting is probably there just to bleed pressure of the system in order to work on it. Same as the 123.

Hi,

I´m having a problem with my SLS.

The car rises whem fully load, everything works fine.
Except when I hit a bump or something similar. It feels hard, it´s like when we ride with bad shock in front. The springs go down but it´s not smooth.

What could it be?
Bad rubber bush? The Shock? The accumulator? The Valve?

Thanks in advance
Vasco

Accumulators. It's almost always the accumulators.

I second that.

I never really though about it before but it's funny that the same part can result in two different very symptoms when it goes bad. Hard ride or really bouncy ride. They must fail in two ways. Not sure how though.:rolleyes:

What I've heard is when the diaphragm fails, initially the nitrogen mixes with the hydraulic fluid, forming bubbles that make the ride bouncy for the same reason your brakes get spongy when they need bleeding. Eventually the bubbles purge out and then the ride gets hard, because all the compliance is gone from the system.