Couple of things to check - overheating and using water can be because the head gasket has gone and this causes the water to go into the engine. The way to check is to have a look at your oil dipstick - if it has greyish deposits then water has got through. It requires the top of the engine to be taken apart and a new gasket to be fitted.
Overheating can also be a faulty thermostat which works by letting more water go through the system as the engine warms up - if faulty it does not let enough water into the engine and it overheats. This is the cheapest fault - lets hope it is this one!
simon pearson, July 2010
check your thermostat is opening ok,if so sounds as if your head gasket is on the way out,check your expansion tank for excess pressure and bubbles in the coolant
