Leak from front suspension - strut return pipe

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Mickey taker
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Leak from front suspension - strut return pipe

Post by Mickey taker »

came back to the car this morning after dropping the kids off at school to find a gooey mess all around the nearside front wheel .
on examination a strut return pipe had slipped off of the metal pipe it normally go's on to.
firstly is it best to lop a bit of pipe off the end before putting it back on the metal pipe ?
secondly should there be anything securing the rubber pipe to the metal one or is it just a push fit?
and thirdly what could have caused it to pop off in the first place ?
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rmattila
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Post by rmattila »

There's no securing, and the popping off may be caused by too high leakage rate through the nylon ring seal in the suspension cylinder.

http://www.rmattila.com/images/remontit ... ppa_avaus/
http://www.rmattila.com/images/remontit ... usitolppa/
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Post by Defender110 »

and no don't lob any off the length, it needs the length to flex up and down easily with the suspension.
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strut return pipe.

Post by bx petrol auto saloon »

Dear Susan.
I had to do a return pipe on mine when I first got her, I would only
lop a bit off first if you have plenty of spare lenght to do that. :wink:
Then you do need to lop a bit off, as original hole in the rubber pipe
will be a tad loose, if you cut it off it will make it a tighter fit onto the
metal pipe, which it needs to be :)
What I have done on mine, is I have put small black cable-ties, on
both ends of the rubber pipe, where they join the metal pipes, for added
security and also, so that I know which ones I have renewed 8)
Hope this helps :wink:
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Post by Mickey taker »

i was only going to nip off a couple of mm to remove any flared rubber at the end to "take up the slack" the cable tie idea was my next option, thanks guys
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Post by Way2go »

If your pipe has "blown" off as mentioned, you are probably passing too much fluid on the strut and it has or is close to totally failing. I had a strut totally"let go" and not funny when you are miles from home. :shock:

Shorten pipes and use cable ties at your peril. If the strut is failing you will blow the octopus apart by the use of cable ties allowing too high a flow rate to reach it. :(
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Post by Mickey taker »

ah ok, I am taking all of this on board, how do I test the strut, have been doing about 360 miles a week in the car and until now the suspension seems fine raises and lowers to all settings etc. Should I double check the pipe is on properly, refill the lhm and seeif it happens again ?
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Post by Way2go »

Basically, the strut should be passing very little (drips) into the return and not a flow of any sort. This is why the returns are called "leak-offs".

If you have a flow, the strut internals have failed. Testing for flow needs to be done statically (engine on, suspension normal) and dynamically (car driven over undulating ground). For the dynamic test you will need to collect fluid in say a plastic bag from the returns to see what is what. The dynamic test is important because the larger leaks may occur if you have wear ridges inside the strut and the seals cannot bridge them in that position.
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Post by rmattila »

There are two pipes, and the idea is that one works as a lekage return, while the other is a breather needed to enable the strut volume to change according to the suspension movements. There is a small metall ball acting as a check valve in one of the pipes, supposedly making that pipe to function as the return line, while the remaining one should flow back and forth.

Very difficult to verify whether it actually works that way, but that's how it is said to be designed.
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Post by Way2go »

rmattila wrote:There are two pipes, and the idea is that one works as a lekage return, while the other is a breather needed to enable the strut volume to change according to the suspension movements. There is a small metall ball acting as a check valve in one of the pipes, supposedly making that pipe to function as the return line, while the remaining one should flow back and forth.

Very difficult to verify whether it actually works that way, but that's how it is said to be designed.
I was of the understanding that fluid flow was in the other direction. :?
I believe the idea is that the ball valve allows air (& any latent fluid in the return system) to be drawn into the strut as it lengthens then closes as the strut compresses causing any leakage fluid to be expelled from the other leg. However it may not be as effective as intended and the pattern strut leg as sold by GSF does not contain any ball valve. The original leak-off returns as sold by the dealer still contain the valve so according to the above theory should act similar to a crude pump in the system.
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Post by MULLEY »

Never seen a ball in a strut return pipe in my life, never knew there was supposed to be one.
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Post by Brian »

here we go then:

Image
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Post by Defender110 »

MULLEY wrote:Never seen a ball in a strut return pipe in my life, never knew there was supposed to be one.
Same as this, mine flow both ways, never seen anything like the picture of Brians???

EDIT: to lube my struts I pump LHM out of an oil can into one leg of the return pipe until it comes out of the other leg, no one way valve stopping progress?
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Post by Way2go »

Defender110 wrote: EDIT: to lube my struts I pump LHM out of an oil can into one leg of the return pipe until it comes out of the other leg, no one way valve stopping progress?
I just checked the recent genuine spare I have in reserve and it would seem that the ball valve has been discontinued in these too. There used to be a "bulge" in one of the legs which is not evident now. :(
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Post by RxBX »

MULLEY wrote:Never seen a ball in a strut return pipe in my life, never knew there was supposed to be one.
Brian wrote:here we go then:

Image
Matt this has all been covered before !
You've obviously forgotten (or have not got the memory of an Elephant like me :lol: ) THIS comprehensive thread (Which you even made a post in) which Brian hosted the same photo showing the plastic valve unit as /\ ?

Then there was THIS thread not too long before the one /\ , in which again you'd taken an active part, by posting in it !
In which I'd linked up into 'Rob Smith.plus.Com' site (at the time it did work showing the same part as in 'Brian's photo /\), but I've managed to find another foreign site (Czech maybe) which I've linked up (below for you and others) to see !

___________________________________________________________________________________________________________

On MK1 models (and early MK2's) the strut returns pipes where made up of five components (Ref. to THIS PDF P8/45) .

#1 Rubber strut saddle (The bit the you strap onto the strut leg with a S/S strap) or Kevans alternative (From BEAL-UK-Ltd as in THIS thread)
#2 Plastic valve (Annotated item11 on PDF) 'A' - over-flow/return pipe.
#3 Plastic push in/on (Plastic straight pipe) 'B' - vent-pipe.
#4 Rubber pipe from (#2 /\ ) to inner wing (push on) steel connection point (Note ! this is not shown in the /\ PDF) .
#5 Rubber pipe from (#3 /\ ) to inner wing (push on) steel connection point (Note ! this is not shown in the /\ PDF).

The (Five piece configuration) IMHO is a better design than the 'All in one' later rubber replacement, as its only a 5 minute job to just replace the length of rubber tube that bridges the front struts across to the inner wing static steel push on connection points when they split/fracture and pi$$ LHM all over the place !
_________________________________________________________________________________________________________

Also note that on the 'All in one' configuration they originally DID have a ball bearing fitted into one side of the rubber chamber to provide the 'valve feature' !
I don't know if you currently ordered an O/E from Citroen that it would come with the Ball bearing fitted (perhaps someone of the forum could confirm this if there recently bought one ?) as you can just hear it rattling about if you had a new one to hand, by giving it a shake (No jokes please :wink:) but most non O/E (after-market) ones never had the ball bearing fitted !

I've got a brand new spare pair of strut return pipes from GSF (which I've just given them a shake) and no rattling can be heard !

______________________________________________________________________________________________________

I was just about to press the 'Submit Button' but had a quick check to see if they'd been any more/new posts in this thread and noticed 'Way2go' posted who now answered the question I've asked above (Whilst putting my post together) so as I going to bed I can't be bothered to change what I've already typed up !
Way2go wrote:
Defender110 wrote: EDIT: to lube my struts I pump LHM out of an oil can into one leg of the return pipe until it comes out of the other leg, no one way valve stopping progress?
I just checked the recent genuine spare I have in reserve and it would seem that the ball valve has been discontinued in these too. There used to be a "bulge" in one of the legs which is not evident now. :(
I hope now that this topic is once and for all cleared up (AGAIN) !

Goodnight

:lol:

RxBX

For Brian, Please note that the image in the FCF LINK seems to have gone astray (possibly since the FCF-Forum/template was modified) ?

P.S. Another useful LINK I came across (Putting all the /\ post together) :wink:

.
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