how dangerous is it to drive a wagon with bad springs and accumulators, SLS off? - PeachParts Mercedes-Benz Forum

bamba · #1 05-09-2008, 04:25 PM

I disengaged the SLS because it will only rise to max height. I'm 99% sure there's an internal leak, and it needs a rebuild.

The wagon is now suffering from a super-droopy rear end, and I can feel every minor dip in the road. New springs and accumulators are in order.

My question is, how dangerous or hazardous is it to keep driving? I can't immediately drop $400 on new springs/accumulators and a SLS valve rebuild. Is this road safe? Will it cause horrible wear and tear on the wagon?

Thanks...

kerry · #2 05-09-2008, 04:43 PM

Probably not as dangerous as the car driven from Indy to TN last week but still not safe, nonetheless. You effectively lack shock absorbers. You could get some nasty bouncing. Driving it a mile to the grocery store on a flat road is one thing. Driving it through the hills of West Virginia something else.

#3 05-09-2008, 05:22 PM

Kerry is right, about the same as a car without shocks. Dangerous but probably okay for short distances. You also risk bottoming out since the SLS is not there to help support the back end, that means you can scrape the differential or the fuel tank on the ground if you bounce it.

bamba · #4 05-09-2008, 06:13 PM

Darn... I just drove it ~ 100 mi today. I can still feel the rattling in my bones.

As a temporary fix, can I manually set the SLS valve? The system works, it just sags when parked for a while (internal leak, right?). Can I lock the valve in the "normal" position, where the holes on the valve housing and valve arm are aligned?

I just need to buy some time before I can drop the cash on a new suspension...

iwrock · #5 05-09-2008, 06:16 PM

Define a while....

I know that on my old W123 wagon, the suspension would deplete over night, and in the morning, you would have to let it sit for a minute to raise again just after starting.

kerry · #6 05-09-2008, 06:20 PM

Quote:

Originally Posted by bamba

Darn... I just drove it ~ 100 mi today. I can still feel the rattling in my bones.

As a temporary fix, can I manually set the SLS valve? The system works, it just sags when parked for a while (internal leak, right?). Can I lock the valve in the "normal" position, where the holes on the valve housing and valve arm are aligned?

I just need to buy some time before I can drop the cash on a new suspension...

Mine's been sagging overnight for a few years. Doesn't cause any problems that I've been able to detect.

bamba · #7 05-09-2008, 06:43 PM

I'm not as worried about the sagging over time. The SLS is disengaged because it will only rise to max height, and I don't want to risk blowing the hydraulic pump/valve/tearing my new boots.

I was thinking about putting a bolt through the alignment holes on the valve body and valve arm (i.e. "normal" position). I wonder if that would restrict the SLS ride height, to prevent it from maxing out?

kerry · #8 05-09-2008, 06:54 PM

I think it's more likely the problem is internal to the valve itself rather than the position the arm is in.

#9 05-09-2008, 07:56 PM

If there is a problem with the piston you will be able to see fluid leaking on the out of the shaft seal. They are a simple hydraulic ram, there is nothing really special about them.

Going flat overnight is no problem, the system flows plenty to overcome that little bit of fluid bypassing the valve.

daw_two · #10 05-09-2008, 08:57 PM

You might could find a used one. I bet there is someone who has one.

Now, let's see, who would that be?

Then you would have one on there while you rebuilt the existing one.

JimmyL · #11 05-10-2008, 12:56 AM

Here's a dumb question: Have you adjusted the linkage from the leveling valve to the rear sway bar? The shorter the linkage the higher the back of the wagon will raise. {rise?}
With the car up on ramps, disconnect one end of that linkage arm and move the arm on the leveling valve slightly and see what the wagon rear end does. Move it in the direction that lengthening the linkage would move it.
Drooping overnight is a different issue.......

bamba · #12 05-10-2008, 12:41 PM

I'm not really concerned with the wagon sagging overnight. I'm more alarmed at the lack of response/control on the SLS valve.

I originally posted about this in a different thread:
http://www.peachparts.com/shopforum/showthread.php?t=221505&highlight=bamba

Before I replaced the rear axles, the SLS appeared to work fine - it sagged overnight, but rose when I started the vehicle. I was concerned that my rear end height was too high, and actually thought that the PO set it too high, which possibly caused the half-shaft boots to tear.

After replacing the rear axles with CVJ's, the SLS rose to max height, and the pump and valve were squealing for dear life. I'm convinced that there was a tug-of-war between the new CVJs and the SLS system, and I certainly don't want to tear the new axles.

So I monkied with the linkage for at least two hours. The valve works wonderfully by hand - I can adjust the height all day long. However, I can't get the valve to automatically stop at a reasonable height. I can adjust the linkage in and out, but never get the car to set right, or even replicate things more than once. Usually, it will either never rise, or fully rise to max height (with the SLS screaming). There is a sticky point around the "normal" setting where valve arm needs a bit of coaxing, which makes me think that the valve needs to be rebuilt.

I'm pretty dumbfounded and frustrated at this point. I figure that the first step is to rebuild the valve (I'll go the $5 for o-rings route, but thanks for your offer, daw_two), and I probably need new actuators and springs, too (judging from the complete sag with the SLS disengaged).

In the meantime, I just want to somehow temporarily keep the rear end at a reasonable height...