pipe seal diameter

[froggy]

Hi, I want to change the Anti sink sphere on my S1 Xantia. The pipe seal can only be sourced from my "Dear Old " Main Dealer!. They are asking what diameter is the pipe ? they are telling me it could be 3.5, 4.5 or 6.5 m/m. Anybody know ? many thanks in advance Terry.

[Xantidote]

3.5mm seals are what you use for such as brake pipe to caliper connections.

4.5mm is what you need for the rear anti-sink - I'm not sure if it's used anywhere else on Series 1.

6mm is what I suspect is used on the larger pipes around the front end, on the pump & regulator pipework (and maybe on the top struts of the top of the range VSX?)

[citronut]

dosent your dealer know how to use there parts look up site, as all they have to do is look at the pipe diameter going to the anti sink sphere

5270 C6
HYDRAULIC TUBE
DIAM 4,5 L=540

this might not be the anti sink part No. specific to your chassis No.,
but all the other anti sink ( MK1 at least ) part No.'s use the 4.5 pipe,

the usual rule of thumb with OE fitted pipe flare nuts is

3.5 pipe = 8mm spanner size

4.5 pipe = 9mm spanner size

6.3 pipe = 12mm spanner size

[Mandrake]

I've always just reused the existing seal when replacing anti-sink spheres and never had a problem...

Just snip off any stray "thread" of rubber at the end of the seal and make sure the smooth end faces inwards when you refit it.

The rubber seals on the Citroen style hydraulic unions are FAR more reusable than most people think as the "seal" is only there to catch a slight weep, 99% of the sealing is metal to metal where the tip of the pipe enters the inner bore, point B below:

[CitroJim]

The rubber seals on the Citroen style hydraulic unions are FAR more reusable than most people think

Quite so. It's been years since I've used a new one. So long ago now I can't recall when...

[froggy]

Thanks guys.

[citronut]

the "seal" is only there to catch a slight weep, 99% of the sealing is metal to metal where the tip of the pipe enters the inner bore, point B below:

i believe the seal being compressed holds the hydraulic pressure Simon, and not just seepage