Did you try burping it like i mentioned?

 

Turn heater to hot, fan on max, radiator cap off and let it idle.. give it a few quick revs and see what happens. i had same problem. My radiator is pretty shit and needs replacing. but temp don't go higher then 1/3 with a good floggin :rolla:

yeah tried burping it mate air came up and all fairly cleared up but still hot. And yeah picked up a cheap radiator just now so ill chuck than in tomorro. and yes heater flat out didnt do bugger all if radiator doesnt fix problem then ill get it profesionally flushed and recomendations good places in adelaide? western subs