Safety valves - are Xantia and BX safety valves same?

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juraj
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Safety valves - are Xantia and BX safety valves same?

Post by juraj »

Hi All

Are Xantia and BX hydraulic safety valves interchangeable?

hmmm ... in fact do Xantias have safety valves.

bye all,

ps while I'm on the subject what about Xantia and BX rear suspension cylinders? They look the same but are their dimensions the same? Are they interchangeable too?
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CitroJim
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Post by CitroJim »

Do you mean the Flow Distribution Valve (FDV) Juraj? Only early MK1 "sinker" xantias were fitted with these and I'm not sure if they're the same as a BX one.

Give Martin at Pleiades a call. He'll know and he should be able to advise on rear cylinder interchangability too.

Martin can also rebuild duff FDVs.
Jim

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KevMayer
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Post by KevMayer »

Hi,

The Xantia suspension has a security valve.

It opens when the system pressure reaches a sufficient level and this is the point when the STOP light goes out because the switch is on this security valve.

Security valve circled in red in following image (front suspension and a small amount of rear susp. Shown off an ACTIVA):-

Image


Not all connections to the valve are shown in this image. There's also pipes to the rear suspension and braking system.

p.s. Jim replied as I was replying... I could have sworn that Jim told me about this valve ??
Cheers, Kev

02 plate C5 2.2 Hdi Exclusive SE (now 170k miles 03/21).

Used to have:- Xantia 1.9 TurboD SX. 1996 Blue & 1998 Silver Activa. + 1992 BX TZD Turbo.
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previous convictions: totaling 52litres of LHM in one go:
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1993 Xantia 1.9 TD SX Mk1 Sinker Silver
1992 XM 2.0 SEi Turbo Manual Anthracite Grey
1982 CX 20 Pallas 'Old Goldy'
1993 XM 2.1 SD Auto Light blue
1993 Xantia 1.9 TD SX Mk1 Sinker light Blue
1982 BX 16 TRS 'Cyril' Vallelunga Red
1995 Xantia 1.9 D SX Auto Dark green
1977 CX 2400 Pallas C-Matic 'Aphrodite' Regatta Blue
1982 GSA Pallas SE Silver Pearl
1980 CX 2000 Reflex Vallelunga Red
1978 CX 2400 Pallas C-Matic 'Prometheus' Midnight blue
1984 BX 14E 'Cecil the slugmobile' Maroon
1987 Fiat Panda 'the mighty panda'
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Post by aerodynamica »

I think that every hydraulic Citroen had this valve since the DS and it's the same part.

The pressure switch (for the STOP light is often available separately too) It also isolates the suspension from the accumulator in the event of a drop in pressure (eg a broken HP pump belt or stalled engine) so as to attempt to use the remaining accumulator pressure for the brakes.

Talking of the FDV valve (I'm having trouble with mine!) there is a repair kit still available from the stealer to overhaul the filters and O rings as they are known to leak externally. The Xantia and BX FDVs are identical but the pressure limiter in each is set to a different level (Xantia is maybe higher)
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juraj
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Post by juraj »

Thanks guys

No not the FDV, but yes the security valve, yes it supplies pressure to the brakes first and last, and yes the one with the pressure stop switch,

ok then that answers it, just that the overflow on mine is leaking quite a bit,

but what about the rear suspension cylinders on a BX versus a Xantia? same? different?

bye all
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AndersDK
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BX & Xantia rear cylinders.

Post by AndersDK »

The rear cylinders are different on Xantia & BX.

The standard BX saloon/hatchback cylinders have an internal diameter of 35mm, while that of an early Xantia have an internal diameter of 37mm.

This difference is noticeable in softness during drive, if you dont match both cylinders.
If you do change both cylinders to the same of either type, I doubt you will feel the difference very much.
The BX cylinders will possibly feels softer with standard Xantia spheres, as they have a lesser volume to displace into the sphere during suspension movements.

Other differences on the cylinders are different lenght on the rods and bellows, but these are easy to interchange on the cylinders.

The outer diameter is still the same and the same protruded ring to hold it against the subframe is still used.
The clip for the bellow is also the same.

The BX cylinders will fit the Xantia rear subframe no problem at all, but not vice versa, as the Xantia cylinders are a later design which has been slightly modified.
The modiification is on the pressure pipe neck. This has a considerably larger diameter on the Xantia cylinder, which makes it impossible to clear the keyhole in the BX rear subframe.

Unless - you modify it back by cutting & filing down the width of the pipe neck to clear the BX subframe.
Then you can make the Xantia cylinder fit the BX.
This is a much wiser idea than you may think : the Xantia cylinder cost is 1/3 that of a BX cylinder :shock:

Notes :
BX saloon cylinder internal dia = 35mm
BX Estate cylinder internal dia = 38mm
Xantia saloon/Estate -> '96 cylinder internal dia = 37mm
Xantia saloon/Estate '96 -> cylinder internal dia = 40mm
Anders (DK) - '90 BX16Image
aerodynamica
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Joined: 26 Dec 2007, 18:10
Location: Glasgow
Lexia Available: Yes
My Cars: 2008 C5 Exclusive Tourer
1993 Xantia 1.9 TD VSX Mk1 Sinker A.K.A Slugmobile 13'
'Old Katy'
previous convictions: totaling 52litres of LHM in one go:
1968 ID19B 'Old Polly' Stellar white
1993 Xantia 1.9 TD SX Mk1 Sinker Silver
1992 XM 2.0 SEi Turbo Manual Anthracite Grey
1982 CX 20 Pallas 'Old Goldy'
1993 XM 2.1 SD Auto Light blue
1993 Xantia 1.9 TD SX Mk1 Sinker light Blue
1982 BX 16 TRS 'Cyril' Vallelunga Red
1995 Xantia 1.9 D SX Auto Dark green
1977 CX 2400 Pallas C-Matic 'Aphrodite' Regatta Blue
1982 GSA Pallas SE Silver Pearl
1980 CX 2000 Reflex Vallelunga Red
1978 CX 2400 Pallas C-Matic 'Prometheus' Midnight blue
1984 BX 14E 'Cecil the slugmobile' Maroon
1987 Fiat Panda 'the mighty panda'
x 98

Post by aerodynamica »

Yea, actually I think the GSA rear cylinders are the same as the BX saloon rears.
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juraj
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Post by juraj »

wow thanks anders for a very informative reply

actually the main reason why asked, is because my bx cylinder belows are torn, and i can possibly get some xantia ones,

thanks all
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