Need 124 SLS diagnostic help - PeachParts Mercedes-Benz Forum

tbenner · #1 07-29-2007, 09:26 AM

Last weekend I replaced the hose from the hydraulic oil reservoir to the tandem pump. The hose was kinked shut so there was no oil returning to the tank as none was getting to the pump. Now it is flowing nicely.

The SLS system still did not seem right to me as it would not return to a level position after loading my sons in the back of the wagon. So yesterday I disconnected the link from the swaybar to the level controller. After messing with it for about 20 it was returning fluid with bubbles to the tank. At that point it would raise and lower the back of the car.

Operating the level controller manually, it lowers in a few seconds but raises the car very slowly at first. After about 10 seconds it raises the car at a 'normal' (hard to explain what normal is... let's say perceptible)

Does this sound like issues with air still in the system, the level controller, the pump, or all of the above? I do not have a means of measuring the pressure suppled to the level controller as the W124 CD suggests. Does someone have another way to deduse where the problem is?

Thanks!

mbdoc · #2 07-30-2007, 08:08 AM

Sounds like thew system is working. they are slow due to the low volume of the pump.

You might shorten the leveling valve rod a turn or two of 1 of the ball sockets.

tbenner · #3 07-30-2007, 11:37 AM

Thanks Doc!

Is the pump a low volume pump by design or maybe wearing out? I was happy just to have the thing going up and down ... now I want to make it right.

Regards,

mbdoc · #4 07-30-2007, 12:34 PM

High pressure with LOW volume is the design.

tbenner · #5 07-30-2007, 12:48 PM

Thanks again Doc!

Now I can move on to the setting the ride height part on the CD. Then the trans filter and fluid change.

tbenner · #6 07-30-2007, 09:55 PM

The system works when I am under the car operating the lever. It takes a little time but it lifts the car body and drops it as the lever is moved. When my sonand I sit in the back of the car it sinks 2 - 3" and the system does not lift us. This could just be an adjustment, right?

When we get out of back the car and check the hydraulic tank it is foaming in the filter like crazy. Accumulators? Is it worth trying to adjust the height before replacing them?

The left side of the car is 1/2" lower than the right. The left looks to be at about the right height in relation to the front wheel; the right looks like it is riding high. The right side also makes a creaking noise as the suspension is extended. I thought it might be the swaybar links. Could this also be an accumulator problem?

Obsessing over this car!