seals for hydraulic fittings.

Bigjoe · Post by **Bigjoe** » 29 Mar 2006, 20:27

Hello all,
I have re-occuring fluid leak from one of the hydraulic screw fittings that go into the distribution block(i think,where the accumulator sphere is?) can i depressurise the system and use ptfe or are the seals available from citroen or anywhere else?

Thanks in anticipation

Joe

AndersDK · Post by **AndersDK** » 29 Mar 2006, 20:41

NOPE !

Its not like housewater systems exploiting 10bar pressures. We are dealing with 170bar here

The device (mounting base) that the accumulator sphere is attached to - is the PR (pressure regulator).

The "screw fittings" here are pipe unions which have a unique seal. These seals are available from Citroen at some £1 (or less) each. To replace you must fully unscrew the uning and remove the pipe from the port. If the old seal does not follow the pipe end, you have to go fishing using a paper clip with an ever so small hook bent on the tip, then hook the seal up from the pipe port.
It appears the seal is some 8mm lenght of precisely cutted LHM hosing and fits over the end of the pipe.
When re-fitting the new seal - you MUST fit the seal over the pipe end - NEVER down the pipe port - before refitting pipe and union. This is because the sharp end of the pipe would cut down the seal if seal fitted down the port first, and then you get a new leak ...

The pipe union is merely nipped up feeling the rubber seal is now starting to give resistance (and being compressed) - never torqued.

The seals are made to fit exactly the diamter of the pipe it goes over. I.e. on the PR it would be a 6.3mm and a 4.5mm seal.

Bigjoe · Post by **Bigjoe** » 29 Mar 2006, 21:45

Thanks,i was pretty sure that i couldnt use ptfe or similar but i didnt know if there was another way of doing it.

I shall investigate further,my nearest dealer parts department is 30 miles away in edinburgh

Bigjoe · Post by **Bigjoe** » 29 Mar 2006, 22:04

Ive just looked at gsf and they list LHM pipe seals in sizes 3.5mm,4.5mm and 6.35mm,any clues which one i would need?

KevMayer · Post by **KevMayer** » 29 Mar 2006, 23:50

The height regulator connections use 3.5 mm. I got some from GSF.

I purchased some seals for this height corrector replacement job from a Citroen main dealer at first. But they really didn't know what I needed. They gave me what turned out to be 4.5 mm seals which were too big.

The best thing to do is to take one of the old seals off and measure the internal diameter. This means having the car off the road until you get new seals. Go to GSF but you may need to tell them their own part number. I know that my local GSF hadn't got a clue that they stocked these seals until I got them their own part number off their web site.

My local GSF (Derby) deals mostly in VW parts apparently "we don't do much Citroen stuff".

DoubleChevron · Post by **DoubleChevron** » 30 Mar 2006, 00:09

Why do you think you need new seals.... I've had NEVER replaced a pipe seal in all the years I've tinkered with Citroens.... Leaking from seals simly doesn't happen.... Unless there is no seal there to begin with !!!

seeya
Shane L.

Mandrake · Post by **Mandrake** » 30 Mar 2006, 00:19

DoubleChevron wrote:Why do you think you need new seals.... I've had NEVER replaced a pipe seal in all the years I've tinkered with Citroens.... Leaking from seals simly doesn't happen.... Unless there is no seal there to begin with !!!

Or the wrong size is fitted....

4.5mm seals fitted to 3.5mm pipes will fit in the hole, but usually weep slightly. Easy mistake to make, too.

Regards,
Simon

Bigjoe · Post by **Bigjoe** » 30 Mar 2006, 09:47

I think its a seal as the supplying garage has tried to fix it 3 times now and ive been watching the area it comes from after cleaning and it seems to be coming from the union area itself,and the seals are the cheapest place to start (as money is very short at the moment

)

dnsey · Post by **dnsey** » 30 Mar 2006, 10:09

the supplying garage has tried to fix it 3 times now

You mean they sold you the car?
When you've sorted it, charge them for the seals and your time, and make sure they refund anything you've paid them to 'fix' it

Bigjoe · Post by **Bigjoe** » 30 Mar 2006, 10:17

Yep the garage that the car came from,they,ve never tried to charge me anything.....ive just been working it out and to get one seal from gsf is going to cost me about £7 with carriage and vat

f00lzz · Post by **f00lzz** » 30 Mar 2006, 10:34

AndersDK wrote:NOPE !

Its not like housewater systems exploiting 10bar pressures. We are dealing with 170bar here
The device (mounting base) that the accumulator sphere is attached to - is the PR (pressure regulator).

The "screw fittings" here are pipe unions which have a unique seal. These seals are available from Citroen at some £1 (or less) each. To replace you must fully unscrew the uning and remove the pipe from the port. If the old seal does not follow the pipe end, you have to go fishing using a paper clip with an ever so small hook bent on the tip, then hook the seal up from the pipe port.
It appears the seal is some 8mm lenght of precisely cutted LHM hosing and fits over the end of the pipe.
When re-fitting the new seal - you MUST fit the seal over the pipe end - NEVER down the pipe port - before refitting pipe and union. This is because the sharp end of the pipe would cut down the seal if seal fitted down the port first, and then you get a new leak ...

The pipe union is merely nipped up feeling the rubber seal is now starting to give resistance (and being compressed) - never torqued.

The seals are made to fit exactly the diamter of the pipe it goes over. I.e. on the PR it would be a 6.3mm and a 4.5mm seal.

CAUTION!! Depends on the year..... later models DO NOT use this type of seal on the pump to regulator pipes.

My experience of leaks on these pipes is that the leaks are generally caused because the regulator is loose which stresses the hydraulic seal (even rupturing the pipe) Also check that the bell housing to engine bolts are tight (4 I think) this will have a similar affect on the seal/pipe.

AndersDK · Post by **AndersDK** » 30 Mar 2006, 22:27

Joe -

If you look close at the PR with the 2 pipes connected - you will see one pipe is slightly larger than the other. The larger pipe is a 6.35mm - the smaller pipe is a 4.5mm.
As Shane mentions above it is very rare that the seals leaks at all. Its always some other reason.

The reason here could simply be the pipe union needs a nip up - some 1/4 - ½ turn.
Other causes I've seen is the pipe itself strained such is has become oval (weven squarish) on the end. This can of course not obtain a tight fit.
I've also seen a single case of a split pipe.

Whatever the case - its not that sophisticated to work on - despite the huge pressure. And parts are cheap.

Go ahead and hunt down the problem yourself - you win the cost of your garage's labour charge 8)

f00lzz · Post by **f00lzz** » 31 Mar 2006, 22:34

http://www.frenchcarforum.co.uk/forum/v ... r&start=15