defender 300tdi . I removed the brake master cylinder as i suspected it was faulty , and the servo had fluid in it . Is that a sure sign the m/cyl was faulty . and apart from a poor brake pedal would there be any other signs symptoms . thanks gerry

Yes. If it's brake fluid and not water? Looking up the servo end of the old MC, is it damp?

Hi yes damp , i wrapped the m/c up as i took it out but it was wet . But i really noticed it when i took the servo off and fluid poured out . Ive just done amongst other stuff the discs calipers and flexi pipes and copper pipes that needed doing . So i kept bleeding it (pressure bleeder) and although the pedal felt ok it was a bit squishy when you pressed the pedal , you could hear it . So i got a servo and cyl ready just in case , But decided as i had them i may as well fit them , glad i did but as i said pedal felt ok'ish so must of been a small weep .

i read it can cause a smokey exhaust on start'up is that right .

Smokey exhaust on an old school petrol engine is possible as the vacuum needed is taken from the inlet manifold . On yours it isn't, vac pump does that.
All tdi's give a puff of smoke on startup.

Thanks for clearing that up , It does as you say on start up but only a slight puff