Mk 1 (possibly also Mk 2) suspension pipe check.

[tontonjon]

Hello everyone.

Just a quick message to recommend a check of the main pipe that supplies the rear suspension. Check for corrosion where it exits from underneath the big plastic panel. The pipe on my Mk1 was rubbing against this panel and the paint came off, leading to corrosion. It burst. I lost all the LDS, just about, and a 10mm piece with the tiniest of holes has been replaced with a union to keep it going long enough for a new car to arrive. Expensive! Avoidable! Worth checking and doing something about before it's too late.

I shall try and get a photo tomorrow.

Jonathan

[white exec]

Careful if using a standard compression (brass olive-type) union to repair a suspension hydraulic pipe. Most common unions are not rated for these pressures, and the olives will not indent the steel pipes. Such repair is prohibited by MoT rules, I believe, and would be an immediate fail. Only feasible as an emergency measure.

[tontonjon]

This? I think this is specific for the job.

http://www.eurocarcare.net/lds-hydrauli ... joint.html

The site says it's for suspension systems and the garage owner is an MOT tester and has extensive experience with Citroën hydro-pneumatics. He reassured me that he used the same thing for repairing Xantias and XMs.

[white exec]

So far as I understand, compression joints are an automatic Fail on MoT inspections, where these are found on braking systems. (Someone here with access to current MoT test rulings will be able to confirm.)

Citroen suspension systems work at similar pressures to braking (up to 170 bar) and that type of joint will not be rated or suitable for that kind of duty. Citroen specify and engineer joints of flare type (an integral part of the pipe), and not slip-on olive type.

An olive joint works by the olive slightly cutting its way into the pipe, and thus providing a non-slip "anchor" to the pipe. For plumbing applications, a brass olive is used in order to cut into a softer copper pipe. On the cars, OE pipework is steel, and therefore any olive used (for a temporary emergency repair) would have to be of a harder grade steel than the pipework if it were to be able to be non-slip.

Repairs or replacements to sections of pipework on these cars must therefore be carried out with the proper flaring tools and couplings, or the complete pipe replaced.

[lexi]

It seems a grey area. Copper brake pipes work at Citroen suspension pressures but I see the problem of brass olives on steel. ECC have been selling that kit for years. I mean, copper brake pipe is not legal in Germany ( needs Cupronickel) but garages here fit thousands of it as repairs. Maybe the ECC brass repair kit just works as there have been no failures? No idea myself.

[xantia_v6]

I don't think that the olive needs to cut into the pipe to make a secure connection, it does need to apply enough pressure to cause some necking of the pipe, which I think should be possible with a brass fitting on a steel pipe if dimensioned adequately.

This does not necessarily translate to legality, which is sure to vary by country.

[white exec]

The use of 'separate ferrule' (loose olive) compression joints in braking systems was specifically prohibited in the 2013 UK MoT manual:

https://irp-cdn.multiscreensite.com/897 ... hicles.pdf

In the 2018 MoT inspection manual, there is no specific mention of this, but the practice remains prohibited in many states.

Reasons for this are listed here, amongst other places:
http://www.brakeconnect.com/top-3-reaso ... n-fittings
https://www.doityourself.com/stry/brake ... on-fitting
Loosening and leakage due to
- vibration
- pressure changes
- temperature changes
- insufficient safe working pressure spec of common (brass) fittings.

Only acknowledged use is as a temporary repair, either to braking or suspension pipework, both of which operate at extremely high pressures.

[tontonjon]

Update; sadly, the car will be "traded in" (and probably scrapped) on Saturday unless someone else would like to take it off my hands. More details? Send me a PM.

Jonathan