Cyril's progress

Tell us about life with your BX, or indeed life in general!
User avatar
Posts: 793
Joined: Sat Jun 07, 2008 11:43 pm
Location: Glasgow

Post by Aerodynamica » Sat Aug 22, 2009 10:19 pm

Ah, not at all Mulley! just some applied swappage that's all 8)
Graeme M

CX 2400 Pallas LPG
2CV6 dolly (SORNed)
Mk1 Xantia 1.9TD SX

'c'est hydropneumatique'

User avatar
Posts: 282
Joined: Mon Aug 15, 2005 11:36 am
Location: France

Post by cauchoiskev » Wed Sep 30, 2009 12:52 pm

Aerodynamica wrote: However, I wanted to have a look at the metering jets as outlined in the Citroën workshop manual. These are very fne disks with a very small hole in the middle. These govern how much of the hydrostatic pressure goes where.
So in addition to the photo in the Sticky about FDVs, the metering disks can be seen removed from the first slide valve:
A. is the slide valve
b. is the metering disk - very small, that divides (sic) the flow 1/4 to the steering and 3/4 to the pressure reg. valve.
c. is the brass spacer between the disk and it's twin brother - the second disk.. not certain why there's two in series but there are. I note that the disks and spacers are identical to the ones used in height correctors for the damper dash pot.
d. is the second slie valve used to prioritise the PAS pressure/ return flow when steering at PRV cut out. It also contains a single metering disk (not pictured here) that was different to the disks in b. Also there was only one disk.
e. is a single disk fitted in series with the filter and holder of the high pressure return from the PRV, the FDV uses this dupme pressure to feed the PAS when the PRV cuts out, the FDV decides whether this flow vs. the HP pump's flow is too much for the PAS and regulates it accordingly. The second valve also decides when the priority to the PAS is to be changed to 3/4 flow to the PAS and only 1/4 to the PRV (after cut out)
Close up
Fantastic stuff, I didn't even know that existed. No signs of those bits on the documents I had seen.

Maybe someone from the powers that be could append that to the FDV sticky ?