Iveco 75E15 Clutch issues - master cylinder?

[_g_]

Not the usual PHmobile, but my 'race truck' is poorly and hoping there may be someone with some experience on here.

Haven't used the lorry for a bit so needed the jump starter. Started it, pulled it back off a leveling ramp (it's a motorhome conversion), moved it around a bit etc and left it running while I tidied up.
Went to go and couldn't find the clutch pedal - turns out it it'd stayed depressed.

Checked the clutch fluid and it looked low (hard to see as it was dark and hadn't got the good torch at this point). Topped it up - only a little bit left in that bottle and it was at least at the minimum. Still nothing (clutch still goes all the way down and stays there.)
Tried loosening the banjo bolt and a little comes out. Tried pumping it a bit and it does seem some is coming out.
Mess about a load and still nothing. I do try and loose the pipe further along, but it's starting to round rather than loosen so leave it.

I took the banjo off completely, put a spanner infront of it then went and pumped it a few times. Looks like there was a decent amount of fluid coming out. However, from pumping it fluid never seem to fill up the bottom of the master cylinder.
Fluid level in the reservoir was going down slowly and I could see a few bubbles - though I'd have expected more.

I'm presuming the problem is somewhere around here.

If it is, do I need to do more bleeding (something I've read suggests you need a pressure bleeding kit) or is there a problem with the master cylinder.

Or something completely different?

[powerstroke]

sounds like the master cly is Fubar'ed !!

[_g_]

Now that it's day light etc so I can see a bit - big pool of dot 4 under the slave cylinder.
Got it off and it's badly corroded under the rubber seal.