SLS Problem: 560SEL is leaking badly, and lower on one side... - PeachParts Mercedes-Benz Forum

johnathan1 · #1 01-17-2009, 11:18 PM

My car has been sitting a bit low in the rear, and is actually slightly lower on the driver's side...putting more weight in the car didn't seem to make the rear rise at all, either, it would just go lower. So I decided to get under the car, and adjust the SLS valve manually to verify that my pump and valve are even working. As I raised the valve, the rear of the car began to rise normally, but then I heard a noise from the front of the car, looked up and saw a large amount of hydraulic fluid GUSHING from what appeared to be the oil pan area...It has always had a small hydraulic fluid leak, but it was only a couple of drips, but for some reason, raising the rear made it get 10x worse.

So I lowered the valve back to where it's at normally (the valve didn't move smoothly, either. It was sort of "notchy" not sure if that's a problem or not...) and the leak went back to it's normal "drip". Is the hose that is leaking a difficult part to replace?? Can I get it from a major parts supplier, or is it dealer-only?

I really don't want this to destroy my engine, as I was talking to Jonathan White from MBCA, and he told me that if the hydraulic pump runs dry, it will seize and effectively destroy the motor, as it is run off of the timing chain.

I have been topping up the reservoir, but it just threw up about a frisbee-sized puddle of fluid in my garage.

I have also noticed a grinding-howling sound from the front of the engine. Please help.

stevebfl · #2 01-17-2009, 11:33 PM

The hose will probably have to come from MB.

While its not good to run any pump dry and i have replaced a score of pumps, I have never seen one "freeze" up. But it sure will be a lot cheaper to fix the hose before the pump fails.

johnathan1 · #3 01-17-2009, 11:36 PM

Any insight on replacing that hose? I have heard a couple people say that it is difficult, but I have absolutely no idea what to expect...any special tools needed?

As for the pump...how do I know that it is, in fact...bad? Will it not spin freely when removed or make noise? I will most definitely be getting a replacement pump from the junkyard if mine is bad, and it would be nice to know that the pump is good before buying it, since I obviously can't test it by running the car beforehand...anyway, thanks for the help!

johnathan1 · #4 01-21-2009, 05:01 PM

Nobody knows?

I also found a replacement hose for about $120 from Performance products.

TylerH860 · #5 01-21-2009, 05:09 PM

I guess everyone else consulted the W126 buyers guide and never had to deal with these issues.

johnathan1 · #6 01-21-2009, 05:24 PM

Quote:

Originally Posted by TylerH860

I guess everyone else consulted the W126 buyers guide and never had to deal with these issues.

Oh, I knew it had SLS problems when I bought it...the price was right, and it's exactly what I wanted, so I decided to deal with it! haha

david s poole · #7 01-23-2009, 10:48 AM

take off the hose.it's a ***** to get to but normal tools will do it.now find a hose rebuilder in your area.they will likely do it for about 30 bucks while you wait.speaking from experience.reason for bigger leak is that valve started calling for fluid and as you now know the hydraulic fluid hose leaks.

johnathan1 · #8 01-23-2009, 12:42 PM

I tried pulling the hose off of a car at the junkyard, and I absolutely could NOT do it...I don't know why.. .. it seems like the fitting that attaches to the pump was never meant to be removed through such a small space. I wrestled with it and cursed for over 2 hours un I finally gave up with the hose only partially removed. Never before has a car defeated me like that. >:-|. I have decided to have my mechanic do the job...even if it is going to cost $350... ouch.

johnathan1 · #9 01-25-2009, 02:47 AM

Alright, had the hose replaced...no more leaks, but the car is still sagging on the driver's side about an inch more than the passenger side. What can cause this??

My mechanic doesn't really seem to know...he thinks it could be a lot of things. Could be bad leveling struts, bad accumulator on one side?, bad leveling valve, or even a squished spring pad?

stevebfl · #10 01-25-2009, 11:09 AM

The system is parallel after the valve in the rear. That neans that both accumulators help each other (one reason to never replace just one). This also means that both struts see the same pressure. Both struts ought to impart equal support to the lift effort with equal pressure. Hard to imagine how they wouldn't.

The lift effort is a cooperation between the steel springs and the force generated by the struts. It is much easier to imagine differences in spring force side to side or even a structural leverage advantage (due to bent or worn components) giving total effort a different effect. Sounds like a lot of work to find the problem. I would probably first check wheel alignment on a lift where the body could be lifted to level. Verification of camber at equal level would go far to elliminate the leverage aspect of bent components. Then I would swap springs side to side if I were working for the government. Most likely, I would then be faced with an owner wishing a answer without paying for testing that would be guaranteed to produce results, at which point I'd probably loose interest.

johnathan1 · #11 01-25-2009, 03:59 PM

Interesting that you mention alignment...on the side that's lower (driver's) it looks like there is much more negative camber than the the passenger side, which appears to be perfectly straight. I sort of assumed this was because of the low ride height, but I suppose it could be out of adjustment or even bent/broken components. I was going to pull out the back seat and have a look at the upper mounts for the struts...think this would be of any help at all?

stevebfl · #12 01-25-2009, 04:07 PM

Look back at my reply. To have a realistic ability to judge you have to take ride height out of the equation. An alignment lift should have a jack. It is necessary to lift the one side till the car is level (measure at the wheel well if necessary). At level the camber should be equal within a half degree.

It is possible that a small difference could exists from blown out mounting bushings on one side, but it would be a small amount.