Catastrophic Lhm Leak

[Gav]

for the first time in nearly four years of ownership my car has let me down this morning.

drive about 100yds when the hydraulic lights lit up and the steering assist vanished. looked underneath to find large puddle of blood. drove back the 100yds ending up with no steering, no suspension height and probably no brakes - but its flat.

it being pitch black i didnt have a chance to check the car but cycling back along the, now wet, 100yd stretch the line of blood was on the centreline of the car and the puddle was under the rear, just in front of the wheels. were the pipes, spheres, block, anti-sink and everything is located.

any advice?

before i get under there in daylight tomorrow can anyone comment on the most likely culprit? pipes i am guessing, but are any of the components likely to have failed so spectacularly?

are the pipes in this location available as of-the-shelf replacements, or must it be a pipe repair kit?

typical really and it follows my belief that these cars must be used everyday to keep them sweet - i even have every single toy and gadget fulling functioning which for an exclusive is good going i think (save for the headlight washer leak). Up until the begining of this year i used her every single day and never ever had a failure which stopped me. now i use her only occoasionally she does this to me!

[steelcityuk]

I've had leaks where the retaining clips corrode through the pipe. Corrosion seems the most common cause - unless a pipe has been left unclipped in which case vibration can cause them to fail. If you know the pipe you need or it's measurements Pleiades can make them up for you.

Steve.

[Gav]

i've now taken a look in daylight and its still not an obvious location. the dripping comes around the cross member just offcentre closer to the near side. feeling what i can with fingers it seems there are wet hydraulic pipes running across the top of this - hidden by the fuel tank.

if this is the case then chances are more than one pipe is close to failing. I see GSF sell pipe by the 50m, so how easy is access to these pipes? tank out / cross member out?

has anybody replaced these pipes before?

[noz]

Hi Gav,

This is a very common problem on XM's. Even worse if they've ever been used to towing a boat trailer and reversing into the water.

All of the pipes which serve the rear components go up and over the rear subframe to get to the front of the car. By that I mean the 6in (150mm) steel tube which goes from one side of the car to the other to whhich everything at the rear is connected. At the point where the pipes come over the top of the subframe and just dip down between the subframe and fuel tank is the worst bit. This seems to get wet and because airflow in this area is poor and it never seems to get dried out.

The pipes are impossible to get at in this location because of the proximity of the fuel tank to the subframe. However, there is a little trick taught to me by DJ. Depressurise the suspension in the normal way (you'll just have to do the best you can with your leak). Jack the body up so that the wheels dangle freely. Support the subframe with another jack and remove completely the two subframe bolts on the near side (passenger). Loosen only , but don't remove the two offside bolts. Gently lower the subframe on the second jack. The near side will drop about 4 inches (100mm) and a gap will appear between the subframe and fuel tank. Access to the pipes and the Anti-sink sphere are now easy.

Pipes are available from citroen pre-made although I have never bought them. I buy the pipe, ends and seals from Pleiades and have a flare tool to make them to suit myself. If you know the length I would make a pipe and send it to you. There's also a Citroen enthusiast does it through Ebay. I'm not sure if they're a member on here though. I think I also saw Roy Mackay (mackay1 on club-xm) offering pipes but I may be wrong. Which part of the country are you in?

The likleyhood of a major component failure at the rear is very low. Corroded pipes ar by far the most likely culprit. When they burst it is fairly spectacular since the pipes are at 60-100Bar.

Since you will find it difficult to fully depressurise the system because of the leak then there may be residual pressure left in the system. I strongly suggest the wearing of safety glasses when working on the hydraulics of a Citroen at all times. I'm not a H&S killjoy. I speak from bitter experience.

cheers

noz

[Gav]

invaluable knowledge, thankyou Noz.

i would not even consider the citroen pipe option as its bound to be excessively expensive. I've re-piped cars in the past, building kit cars based on citroens although i dont recall flaring the ends - i'll have to check in my tool box for those rarely used tools.

i'm in west london (which is useful for GSF!). Have you just replaced the section of corroded pipe or do you take it back to the next fittings?

[Gav]

sorry, another question... are all these pipes 3.5mm?

[xmexclusive]

Hi Gav

Go for the Pliades pipe option as it is not prone to rusting like the Citroen pipe. I seem to recall that all the pipes are 3.5mm but they come to the front of the car without joints. It is easiest to cut in a connector by the fuel tank as the rust is only localised over the main suspension tube. I was amazed how bad these pipes were when I dropped the rear sub frame out out a Preg estate.

Regards

XMexc

This post has been edited by xmexclusive on October 20, 2007 11:29 am

[steelcityuk]

The only pipes I've replaced have been back to the local connectors or valves which is a easy and tidy way of doing it. All the rear piping is 3.5mm (as far as I know) except the anti sink sphere at 4.5mm and the large stuff for the struts if the car is hydractive. GSF seem to stock the 3.5mm seals at 45p each. Pleiades have supplied me with a couple of anti sink pipes on next day delivery and it still only came to around £10 each.

The white XM I bought did have quite a few of the pipes already replaced, these were mainly joined under the left hand side just in front of the rear wheel arch near the sill.

As noted by others once you've replaced them corrosion shouldn't be a problem.

A photo here of the corroded fixing and pipe -

http://www.flickr.com/photos/7328220@N02/1...57601606596399/

Steve.


This post has been edited by steelcityuk on October 20, 2007 11:55 am

[Ken newbold]

This is one problem I've been dreading. OK it hasn't happened yet, but.

I've come across one or two XM's with this problem, If the pipes are 3.5mm I'm not too worried as I have pipe and tool for making ends. 4.5 would be more of a problem though.

One of our members currently has one for sale on ebay with just this problem,

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the sound of thinking

[UFO]

Must be the season for it! I had the main feed line from pump to reg fail near Canberra the other day. Left a great puddle of greenblood on the relies' driveway. Fortunately we have Premium roadside assistance coverage, so the XM was flatbedded to a workshop near home and we had a hire car provided for the 250km drive home. Instead of arriving home by 5pm we got here at 11pm.

Car sitting at the local Citroen workshop waiting for time and space as there is a big job to get an SM back on the road for a keen purchaser.

This time I replace that line with a high pressure rubber line with Citroen ends swaged in.

[jorgy9]

What are the benefits of doing so? Where do u source that rubber pipe that can withstand 170 bar? Has it been done again?

I'd be interested to see photos of the result.

cheers
George

[UFO]

It has been done on many cars in Aus for various reasons. On DSs it is easier for maintenance etc to move the regulator from the side of the engine to underneath the spare wheel - simple to change an accumulator then. On CXs it was done to remove a long and often failing metal line from pump to reg I believe.

Standard HP rubber hose from a hydraulics shop will operate at up to 2750psi IIRC, so it is within limits of the Citroen system. In doing this job you end up with the majority of the line as something that is designed to flex and take shock at the same time. XMs already have some lines like this anyway. Take the strut feeds - they go metal>rubber>metal>rubber>metal!

If you have ever seen the pump to reg line on an earlier V6 XM where it runs over the top of the gearbox and down to the front of the box you would understand the twists and turns it has to go through. You would also appreciate the joy of having to remove and replace the line...

I am expecting an opinion from the mechanic today. Perhaps if I am lucky it is only one of the other lines nearby...

[Gav]

Ok, so the car has been on stands with the rear subframe dangling for the last week or so while i got sent away with work. Hope the neighbours dont mind. A very neat trick with the rear subframe. Came down a treat.

Given that I will be replacing all the hydraulic lines at this location can the subframe be dropped completly without damaging any other connections? I will cut through the four or so hydraulic line before hand.

I'm looking to get new pipes for all the parts up and over the cross member (including the fittings to the valves / height block, etc?) and tieing them into the existing pipes under the fuel tank. Do i need a tool for flaring the cut ends or will the connector fit straight unto cut pipe?

BTW - gsf no longer stock hydraulic pipe, despite what the online says. Apparently the online list is very out of date.

[dean]

Yes beware gsf's online catalogue is very out of date, it said my new radiator was £98ish but it was actually £140 ish

[techmanagain]

I am presuming that you will be getting the pipe(s) fromPleiades also the connectors and the pipe seals ? If so, Martin will supply everything needed, I would expect, as he is very efficient. The pipes will presumably be fitted with their connecting nuts and so will have been flanged before fitting (if they have been cut to pattern lengths). If you have asked for lengths of pipe plus connectors, etc., then you may have to fit the nuts and flange the pipe-ends yourself after sliding the nuts onto the pipes. Be sure before you start !