replacing pipe on self levelling

[mattc]

The self levelling on Nat's estate has sprung a leak in the pipe work. It is the long section of pipe running the length of the cars underbody. the pipe (the inner of the 2 that run the length) had corroded under the rubber grommet that holds the 2 pipes to the bodywork - I presume over time a bit of gunk has worked its way in and started the rot.

So my questions are:

1. What is the pipe number I need - I looked on the Russian site and think its 1243201954 or 4353. Can anyone confirm this?

2. Is it simply a case of following the 2 ends and unbolting?

3. When I do this will I lose all the fluid in the system? I am guessing not all so do I drain it all and refill with a few litres and is there any alternative to the expensive Merc stuff?

4. what should I protect the new pipe with to stop it corroding over time?

5. Any bits of advice when doing this job?

thanks in advance

matt

 

[Number_Cruncher]

1) I would fit both pipes (but one a time to avoid any potential for confusion), as the other pipe will be in a similar condition to the leaky one

2) In theory, yes. In practice, you'll find the routing around the subframe a challenge.

3) You shouldn't lose all the fluid. Although it is a bit expensive per litre, you don't need much - 2 litres is more than enough to renew all the fluid in the system.

4) I expect the new pipe will outlast the car (unless you plan on another 20 years or so!), but, some waxoyl would be OK.

5) Keep all the pipe ends and female threads on the valve, pump and reservoir plugged as soon as you open the system - dirt is THE enemy of hydraulic systems like this.

Good luck!

 

[mattc]

Thanks for that - good idea about doing both.

 

[mattc]

I went and had another look at this - removing the old pipe will be relatively easy (cut/bend/chuck away ) but feeding the whole new section will be a mare I think ;especially around the subframe and the engine bay. As mine is split on a straight section is it possible to have a "bridging" piece made up using pipe and some compression joints?? Whilst it is always more satisfactory to fit a new OEM part it seems an awful lot of hassle when a new section would be so much quicker!

If it is possible any recommendations here in the West Midlands of who to ask - and does anyone know the O.D and I.D of the pipe section?

cheers

matt

 

[moakesr]

Compression joints for SLS lines A0039979172

If you can cut out a small section ( 1cm or so ) you could use one of these.

Richard

 

[mattc]

Does the cut section need any internal suport? Does the joint come with anything like that? I appreciate the ID is rather small so it may not be possible.

Are the SLS lines the same material/diameter by te way?

 

[moakesr]

They come with internal supports, all very tiny, but supports the pipe nicely.

I bought two, but couldn't use them due to the leak being on a bend. I ended up dropping the subframe on my R129 and putting in all new lines.

Sorry wasn't clear, SLS self levelling suspension, it's the same stuff for sure.

 

[mattc]

want to sell one if you can find it?

 

[moakesr]

Sure, I know exactly where it is.

Inchcape says £4.71, shall we say £4 including p&p?

I need to find an envelope or jiffy bag, so it might be a couple of days before you get it?

PM me details if you want me to send it.....

 

[mattc]

Finally got round to doing this properly today. I needed an extra bit of pipe and a 2nd compression joint as the pipe had actually corroded through in 2 places. cutting out the offending bit meant I did not have enough pipe to work with hence Mr Walker had supplied me with the extra section. Having used the joints which really are a nicely "over engineered" piece of kit I find the clamps that attach/support the twin pipes to the underside of the car have corroded (more precisely - the threaded section hanging down from the bodywork has corroded and the plastic will no longer attach to it.

So the question is what recommendations do you lot have of how I fix it so the clamps do their job and hold both pipes securely to the underside of the vehicle?
matt

 

[moakesr]

Hi Matt,

Glad to hear the joint worked fine, you should have said if you needed another one urgently. I still had another in my spares cupboard!

Sounds like you need something welded, or perhaps drill a small hole and use a pop rivet to attach something which can be used with ty-wraps?

 

[mattc]

Sorry for the thread revival

Everything was going so well; the replacement pipe/fittings have done their job, car breezed through its MoT and I even got a compliment on how tidy the replacement section was (all down to those MB SLS connectors which really are a nice piece of engineering).

Having left the car on the drive for a few weeks she has settled on the rear near side. Turned over engine and went for a few hundered meters drive - side dtill stayed low. Ride felt a little bit bouncy but not excessively and as I have been driving a first generation sportline recently I good just be imagining it. the SLS fluid levels have not dropped though I confess I ran out of fluid so I am about 100ml off being up to the minimum mark .

Could this be the source of my problem or has something else failed? (she is nearly 200K to the good though I "think " Andy K may have changed the spheres years ago on her - I will check with him)

 

[oilychariot]

Slightly low fluid caused my rear susp to behave poorly - seemed to do a bit of sorting itself out when the level was put right, now rides better.

Is the system self-bleeding? Used to v. old Cit suspension where there is a supply and return.

 

[martinhamilton]

Hi Matt,

This sounds exactly like my problem and I've just ordered a couple of the compression joints. I'll try to take some pictures of the job, but wanted to ask how you cut the pipes and where you got the replacement section from? I have a hacksaw or a pipe cutter that I use for plumbing purposes, which as going to be my preferred tool as there is less metal flying around, but wanted to see if you had any recommendations?

Hope your car is still okay.

Cheers, Martin.

 

[martinhamilton]

Hello, just thought I would update you all on this job. I got the compression joints from the Mercedes Dealer (a bit of a saga as they didn't call me to tell me they were in, so I called them 5 days to be told they were in. Rushed down to get them only to be told they can't find them, despite the computer showing as received. They ordered for next day as it was a bank holiday weekend, still didn't call to tell me they were in then when I did call they had found the others as well! I'm not sure I can use the sort of language I was thinking at the time...).

Anyway, back to the repair. I got hold of some 6mm nickel coated steel hydraulic pipe from a local supplier, as Mercedes couldn't supply this nor tell me the size of the pipe, but once I had the joints I could go in and get the right size. Then it was under the car with a pipe cutter (one I had from Ikea last time I fitted a kitchen) to cut back to some good (ish) metal and then cut a new section. I cut it approximately 5mm shorter to allow for the joints at either end. I could have gone shorter, but there is a bit of flexibility and would rather it was all under a little bit of compression, rather than tension. Cleaned up the old pipes and made sure that all of the collars and nuts fitted okay, then on with the new sections. In all not too difficult. I've attached a few images of the joint and the finished job, just in case these help. As you can see, I also had a problem with one of the brackets going rusty and falling off, but that has now been welded up and a couple of P-clips screwed to the new plate holding the pipes in place, although I don't have any pictures of that.

By the way, I didn't drain the system of oil beforehand, which was a concern before I started. The new bit of pipe came with a couple of bung in each end, so I used those and worked on one pipe at a time. I had a little leak out, but caught it with a drip tray (and my forehead...) and as long as you don't have the car running there isn't any pressure in the system. I was also trying to find out if it needed to be bled and have read contradicting articles online. One said it is self bleeding and as it has a return to the header tank that is not pressurised, I assumed this must be the case. I didn't bleed the system and it seems to be okay so far, but will let you know if there is a problem.

The old girl (Helga) is having her MOT today, so fingers crossed that all is okay.

Cheers, Martin.

 

[martinhamilton]

Just to let you know Helga passed her MOT without any problems.

Now I just need to plan when I'm going to replace all of the hydraulic pipes, but that will mean taking down the rear sub-frame and any additional work that entails. As she is getting on a bit, it is probably not a bad idea, just not something I'm looking forward to.

Cheers, Martin.

 

[moakesr]

When you drop the subframe, be ready to replace the fuel lines and the brake lines, they won't be in a good state.

When I replaced the ADS/SLS lines on my R129, I dropped the subframe and was horrified what I found

 

[martinhamilton]

Hi Richard,

Yes, I was planning on doing all of the pipe work whilst I could as it seems a wasted opportunity otherwise. The other jobs I will probably have to do are the sub frame mounts and the diff seals as well as possibly shot-blast the subframe and re-paint it all. Looks like there is a fair amount of surface rust all around under there, so want to make sure it is seen to and has some protection.

Thanks for the advice though. I am expecting more work than I would hope for though.

Did you make the pipes up yourself, or get them from Mercedes? I have bought some brake lines from them in the past and they are just straight pipes to the right length and you have to bend accordingly, which seemed a bit of a swizz to me...

Cheers, Martin.

 

[moakesr]

I made up my own lines, lots of cunifer and external bending springs.

I cut out the old lines, which were held together by rust and the plastic liner, and then spent many hours creating replacements which matched the bends exactly. Took a while, but I was happy with the result.

 

[martinhamilton]

As I think I will have to do all the bending anyway even if I buy the official Merc ones, I don't think it is too much extra to make up the whole thing and end up with a better job.

Did you use cunifer for the SLS lines as well? Was that in 6mm, or did you make them all from the same thickness as the brake lines?

Sorry for all the questions, just want to plan ahead.

Cheers, Martin.