Well, my Xantia TD is back in working order again. It turns out that the problem was just a teeny bit more serious than I ( or anyone else! ) thought.
Put simply, the HP pump had more or less come apart at the seams. Fortunately it was repairable, but here's a warning to Xantia owners - believe me, you don't want to lose nearly all your hydraulic fluid in ten seconds...
The cause was an overtightened auxiliary drivebelt. Something that I never bothered to check when I bought the car, after all it was in good condition and didn't squeal. Over time this forced three retaining pins loose, and finally wrecked the seal. When the pump was removed it came apart in the mechanic's hands.
Check those drivebelts, folks!
Stu.
Up and running - and a warning...
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