Burst suspension pipe at rear

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xantia_v6
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Re: Burst suspension pipe at rear

Post by xantia_v6 »

The problem with compression joints (and the UK MOT) I think has 2 factors:

1. A brass compression fitting on a steel pipe is not always easy to tension correctly such that the pipe is deformed to lock the olive in place.
2. The UK MOT is a visual inspection only, with no disassembly permitted, so an inspector has no way to determine if a non-original compression fitting has been appropriately and safely fitted, so all such fittings have been banned.

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ksanturion10
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Re: Burst suspension pipe at rear

Post by ksanturion10 »

white exec wrote:
04 Oct 2020, 21:04
The prohibition of compression-olive joints for braking systems is part of the detailed UK MoT regulations.
I will try to dig out the details when I get back to base.
As I said before, don't want to delve into the matter, I'm sure its all made up already :D.
xantia_v6 wrote:
04 Oct 2020, 23:28
The problem with compression joints (and the UK MOT) I think has 2 factors:

1. A brass compression fitting on a steel pipe is not always easy to tension correctly such that the pipe is deformed to lock the olive in place.
2. The UK MOT is a visual inspection only, with no disassembly permitted, so an inspector has no way to determine if a non-original compression fitting has been appropriately and safely fitted, so all such fittings have been banned.
1. There is a whole universe of brass (messing) compounds, that I'm pretty sure will sustain all the requirements of such a joint. But I'm referring steel hardened olives with steel fittings, so if you use the prescribed material and surface smoothness for the pipes, don't see how it will be inappropriate, when the producer states, that it can sustain 250 bars nominal pressure for hydraulic fluids. You must acknowledge, that this is a machine part, not something made in the garage - not that people can't come up with what they decide :roll: .
2. Yeah, kind of non sense reason I could also come up with ;). Can't mess with UK MOT from here, its too far west for me :) .

Apart from the jokes, those compression fittings are so easy to fit, that anybody can do them in no time.
It is still reliable for me, and you know, that I've putted it at the most unforgiving place ;)

BR
Martin

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KennyW
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Re: Burst suspension pipe at rear

Post by KennyW »

Hi All,

An update finally got the fuel tank lowered and confirmed it is the rear supply hydraulic suspension pipe. It has rusted at the plastic pipe holder at the rear of the tank.

There are silicone pads also fitted but this still didn't prevent the water running down the pipe and gathering at the bracket rusting through the pipe the rest of the pipe looks okay but!!!!!!!!!!!!

Waiting on the arrival of new pipe to fit and as the BOL refitting is the reverse of removal. :rofl2:

Kenny

PS Is there anything on service Citroen about the 'o' ring sizes ?

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GiveMeABreak
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Re: Burst suspension pipe at rear

Post by GiveMeABreak »

KennyW wrote:
04 Oct 2020, 17:30
Until I have the fuel tank removed I don't know which pipe it is but I suspect supply pipe rather than the return.

I think it maybe a bubble type flare.

I've looked at service box but can't find anything directly related to the pipe.

Marc, can you look if possible my VIN is VF7**************[VIN obfuscated, can be read by forum staff].
Kenny
Sorry Kenny - I've only just seen your post - catching up. Here's the rear pipes - Supply and Return with part numbers if you don't already have these.
image_2020-10-08_174643.png
image_2020-10-08_175000.png
Return Piping Rear Suspension
(1) Hydraulic Oil Back Harness: 5270SE
(2) Hydraulic Oil Back Harness: 5270VV
(3) Hydraulic Oil Back Harness: 5270WR
Supply Piping Rear Suspension
(1) Hydraulic Tube: 9807562180
(2) Hydraulic Tube: 5270VP
(3) Hydraulic Tube: 5270VG
(4) Hydraulic Tube: 5270VF
(5) Hydraulic Pipe 2 Way Union: 5280T3
(6) Pressure Sensor: 5273A2
I can't remember now which one of mine went on the rear, but I had one replaced for a small leak. Apparently it is where the pipe bends in manufacture that creates a weak point for corrosion and ultimately a fail.

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KennyW
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Re: Burst suspension pipe at rear

Post by KennyW »

Thanks Marc,

It's no 1 that has failed just above the fuel tank. All I need to know is the seal sizes. This is about 4.80mm dia pipe. seal required 5.5 x 4.5 x 1.0.

No 3 is also removed from 2 way union and this pipe is about 3.5mm Seal 4.5 x 3.5 x.1

Can't find anything giving sizes as seals are prefitted to part.

Out with my measuring stick !!!!!!!!!!!

Kenny

Update Just measured the o ring and I'm way out Pipe is probably 4.75mm, thread nut is 11mm, o ring 7.5mm x 4.5mm x1.5mm

Smaller pipe is 3.5mm o ring 6.5mm x 3.5 x 1.5

Flare end would appear to be a single flare.

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KennyW
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Re: Burst suspension pipe at rear

Post by KennyW »

Hi All,

An update, I have removed the pipe and it is a tiny hole the size of needle where the LDS came out.

I have removed the flare ends and this is what I found:

The pipe end appears to have single flare or is it the pressure of the pipe being screwed in causing the flare.

The pipe end would also appear to have a citroen bubble as per xantia's etc.

As per photo
5270half1.jpg
5270half1.jpg (15.5 KiB) Viewed 20 times
IMG_0070.JPG
IMG_0072.JPG
IMG_0073 (1).JPG
IMG_0074_LI.jpg
Circled is the citroen bubble and in the next photo metal 'seal' is forced over bubble flare.
IMG_0072_LI.jpg
Can anybody confirm my thoughts ?

Kenny

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ksanturion10
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Re: Burst suspension pipe at rear

Post by ksanturion10 »

Nope :)
It resembles an adapter part for transferring the nut's axial clamping force over the smaller PTFE (I presume) back support washer for the green O-ring... 8-)

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KennyW
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Re: Burst suspension pipe at rear

Post by KennyW »

Thanks for the reply,
Just a more complicated version of the Xantia and previous hydraulic citroens then !
Kenny