I managed to get 3 brakes bled today but when i got to the last wheel the nipple had been completely rounded so i tried very gently with a small vice-grips and it wouldn't budge so i left it alone before i took it off completely!
So my question is how will it affect the car if at all?
I took it for a spin straight after and there wasnt much to complain about,the pedal was a little spongy,but no more so than my other Xantia
In an ideal world you'd want to bleed that one too to ensure there is new LHM at each wheel. I would soak it in penetrating fluid and leave it while you go and buy a new bleed nipple. Then in a few days have another go. You could try gentle heat from a heat gun or blowtorch if you wish bearing in mind the caliper body is alloy I think so be careful!
Former Proud owner of a 1994 Citroen Xantia 1.9d and BX 19RD
Now driving an Alfa 159 but god I miss the Xantia!
Go to B&Q. buy a set of their 1/4" Drive deep sockets about £10,
select the size smaller than the nipple size, say a 7mm if it's an 8
then tap onto the nipple 'chasing' new flats as you go, once down at least a couple of mm's
(all the way if poss.) then without removing fit an extention (if needed) and rachet - undo, fit new nipple.
You may only get one chance at this so no short cuts and the socket maybe useless
afterwards