Repairing hydraulic hose for SLS hydropneumatic suspension on TD
 

Everyone with a wagon will eventually face the necessity of replacing the rubber high pressure hydraulic hose which runs from the pump on the head to the metal fitting on the passenger inner fender under the air cleaner. I just did mine. It's simple and inexpensive. All you need is a comparable length of high pressure hydraulic hose. I used Gates 6G2 3/8 9.5mm. It cost $14. The hose fittings are easily reusable (despite what two hydraulic hose repair shops told me).
Remove the air cleaner. Remove the hose at the banjo fitting at the pump and at the metal line at the fender. Note that that the fittings on the hose are made up of a large round outer portion which goes over the hose and an inner portion threaded into othe outer portion. Hold on to the outer portion with a vice or vice grip and unbolt the inner portion. Once the inner portion is removed, unthread the outer portion off the rubber hose. IT IS LEFT HAND THREADED..
Be careful at this point. The OE hose has about 30 small plastic inserts inside the hose. Carefully let them drop out onto a clean surface, noting the orientation of the insert. You will need to insert them back into the new hose.
Put the outer portion of the fitting onto the new hose. (REMEMBER IT IS LEFT HAND THREADED AND SCREWS ON TO THE RUBBER.). The hose will stop at a shoulder inside the outer fitting. Screw the inner portion into the outer portion. It is tapered and fine threaded. You will need to push down on it with moderate force to get it far enough in the hose for the threads to bite. Before doing the other end, reinsert the numerous plastic fittings. Put the fitting on the other end and reinstall the hose on the car.
With these instructions, the job should take about an hour and half. It could be done on the road if you have a second person to hold the vice grip when disassembling the fittings.
My hose sprang a leak on a road trip. No new hose was available so a mechanic took off the old one, cut off the leaking end and reinstalled the fitting. He cursed and swore for quite a while trying to get it back together. This was because he never figured out that the outer portion IS LEFT HAND THREADED. I only discovered it by accident after trying to thread it on for about 10 minutes right handed, and then when trying to remove it to figure out why it wouldn't go it, presto, it threaded right on as I unscrewed it.


By the way, the fittings on the power steering hoses look to be the same so I bet replacing them is just as simple and inexpensive.

Way Cool!!! Thanks!

Please
 

A couple of pictures would make this a good DIY for the wikki. :)

I think NAPA will them them for cheap..... the older one of mine is seeping badly.

Too late.

NAPA refused to make mine when it started leaking, saying they did not have the correct hose. It's not worth paying NAPA. If you have the skill to unscrew the hose from the pump, you have more than enough skill to replace the fittings on the hose.
Other people experienced what I experienced; hose shops saying they couldn't reuse the ends and wanting to cut the end off and braze it to one of their fittings. This is entirely unnecessary since MB made these fittings so easily reusable.

Darn
 

Perhaps someone else can add pictures later. :)

Maybe John can take some pictures when he does his. There is also another poster currently working on this problem. Perhaps he might do likewise.

I will indeed take pics when I start on my hoses.

Thanks Kerry! Your post goaded me off my butt into 100 degree, 100% humidity to finally under take this repair....she's been puking fluid for a long time.

It was just as straight forward as you said...LEFT HANDED THREAD was the big key. Had the usual "we don't have anything that fits a Mercedes" from the NAPA counter kid....finally told him it was really for an old Case tractor and low and behold they did have the perfect type hose!

BTW, while mine did appear to be the OEM hose with the MB emblem and all, there were no little plastic spacers in there....which bothered me not in the least!

Simple repair, well written instructions. Sorry, I don't do camera work...but pictures really weren't needed.

I gave mine to an excavator buddy, who brought it to a heavy equipment shop, they replaced the rubber and reused my fitting for free.
It cost me a 12 pack of Coors.

truck air brake lines are similar. I was not aware that these were the same, thanks for the tip...

I completely forgot to take pictures.
it was a MAJOR pita to get the center part back in... I just cut the leaking part off, and put it all back together... there is quite a bit of extra hose here. I had to ream with a pocket knife the center of the hose about 1/4" down... and back the outer fitting back quite a bit to get the center part in enough to thread it in. OK, the hose is quite thick, and the center is quite large. when it threads onto the outer part, it compresses the center quite a bit.

well, this did not hold. shortening the hose, only held for a few weeks. and POP out it came. I will try and get some new hose from napa. the 3/8 hose looks too small to thread the center in.
it popped off a 10:00 the other night, so again I did not take pictures... maybe when I put the correct hose in I will... I just pulled a good hose off my parts car and drove away.

I have a leak somewhere in my system that I will be addressing in the next day or two. I will try and document although I am nearly positive it is in the rear.