Dorser or dump valve

caeclyd · Post by **caeclyd** » 30 Jul 2004, 01:45

I have just been offered a Citroen estate 1.9td 96 N.
There are a couple of problems clutch and timing belt but the one that concerns me the most is that the dorser valve needs changing.
The symptoms are very aggressive braking with no feel on the peddle.
It has been diagnosed as the dorser or dump valve (on the bulk head) by citroen mechanics.
<b>Is it a difficult job to change? </b>
I have access to a spare valve from a donor vehicle.
Your help would be appreciated.

AndersDK · Post by **AndersDK** » 30 Jul 2004, 02:39

I presume you mean a Xantia ??
Then it's the brake master (pedal) valve we talk here - in Citroen world designated the "doseur" valve, which in french simply means a "dose" valve, to adjust the flow (dose) of hydraulic pressure out to the brakes.
Because this valve is located low down on the bulkhead in the engine bay, right behind the engine, it's a pig of a job to access and replace the pipeworks fitted to the valve.
Normal procedure is to remove the fixing bolts (nuts ?) from inside footwell, then simply carefully pull down valve for easy access of the piping. Piping is delicate, easy to kink, and pipe unions may have rust seized in pipe ports, making it a nerve stressing job.
No wonder it's quite a beefy job on a garage bill.

ItDontGo · Post by **ItDontGo** » 30 Jul 2004, 04:43

If there is air in the brakes they suddenly come on really sharply after a slight delay. The pedal will not feel spongey like on a normal car with air in the brakes either. Most neglected cars seem to benefit from a good 'Citrobics' workout followed by a brake bleed.
The brakes on a Citroen feel weird even when they are new!

caeclyd · Post by **caeclyd** » 30 Jul 2004, 12:34

Thanks for your response.
" the brakes they suddenly come on really sharply after a slight delay" that is exactly what happens.

Anders that is the component I am talking about it is in a pig of a location. Do you know if there are any special tools required?
Idontgo you suggest a Citrobic work out ? followed by a brake bleed.
Does this mean work the hydraulics up and down a few times ( with plenty of lhm in the system) ?

caeclyd · Post by **caeclyd** » 30 Jul 2004, 12:59

Anders,
I have just found your link to the citrobic work out. I will try this and then have a bash at bleeding the brakes.

ItDontGo · Post by **ItDontGo** » 30 Jul 2004, 17:49

Yeah. Raise it and lower it a good few times and then bleed the brakes. I have had BXs and Xantias with these symptoms and bleeding the brakes has always worked for me. The rear brakes especially always seem to have lots of air in.

AndersDK · Post by **AndersDK** » 30 Jul 2004, 18:41

caeclyd -
if it cures the problem with Citaerobic & brakes bleeding - dont go tell the garage [8D]
- just tell them how easy these cars are on DIY [:D]

caeclyd · Post by **caeclyd** » 31 Jul 2004, 18:02

Anders,
No it did not work.
As I already own a Xantia it was to be a replacement BUT to an enthusiast
http://www.andyspares.com/discussionfor ... IC_ID=8472