Head gasket??? Leaking radiator??? No water???
Sorry I am rubbish at techie stuff, but I am sure someone on here will be along to help soon.
Jen

GO ON JEN......go girl...
JOFUS..could be....water pump...thermostat...radiator blckage...air locked system..the list goes on but check these things first
is it losing water .can you see any leaks ...any steam when hot...is their oil in the water.(expansion tank)..give us a bit more information...