thanks guys but iv ran the car disconnected the return hose to the header tank and let it run out and did it a few times as the water was a orange colour we seem to think it is the heating system behind the dash instead maybe blocked with crap etc ....... it will boil but only if u leave it for like 15 mins running on tick over then the fan kicks in lol the coolant is renewed everytime i drop the water and iv done it 4 times in the last month lol but still no heating