Partially fixed Xantia brakes, help!

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CitroJim
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Re: Partially fixed Xantia brakes, help!

Unread post by CitroJim »

citroenxm wrote:As the first post says.. 94 Lx sinker with no Abs...
In that case then... If all else fails and the accumulator is proved good it would be a good idea to have the FDV checked over by Pleiades. It may be a bit leaky and starving the braking system of pressure.

Can you hear the FDV doing a lot of hissing?
Jim

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cc101
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Re: Partially fixed Xantia brakes, help!

Unread post by cc101 »

Thanks Jim, the fdv valve can sometimes go without hissing for well over a minute then just normal regular hissing, every 30 seconds or so.
Xantia 1.9 TD 1993 (sinker)
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CitroJim
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Re: Partially fixed Xantia brakes, help!

Unread post by CitroJim »

Right, another test of a leaky FDV can be if the car struggles to get to full high on the height lever on idle. If it's leaky it might need some persuasion by revving the engine to get right up high.

How fast is the pressure regulator ticking? Does it occasionally go mad and tick like a ten-bob watch?

I know on a Sinker it can be hard to hear the ticking but of you use a long screwdriver as a stethoscope on either the pump or regulator you should be able to hear it. A good listening test on the pump is this: when the regulator is cut out and up to pressure the pump is effectively idling and will be near silent. When it's working to build pressure the pump will sound like a little machine gun. You should hear a burst of machine gun fire coincident with each regulator tick. A normally functioning system will run silently for the most part with a regular short burst of machine gun fire as the regulator cuts-in which soon ceases as the regulator cuts out. Constant machine gun fire or very short stretches of silence between is indicative of a weak accumulator and/or a leaky FDV.
Jim

A bit of a Citroen AX fan...
Gibbo2286
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Re: Partially fixed Xantia brakes, help!

Unread post by Gibbo2286 »

citroenxm wrote:As the first post says.. 94 Lx sinker with no Abs...

It was a bit early for me Cit. :-D
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