I developed an overheating problem on the way back from the Spring Rally, The car overheats if I am traveling at speeds in excess of 60, but will drop whan I turn the heater on of lower the speed.
I have changed the thermostat, and recently the water pump and flushed the system, this has not fixed the problem. The radiator seems to be hot at the top and bottom but cool in the centre. The inlet hose is as hot as the outlet, could this be a sign that the radiator is not working. Any Ideas greatfully recieved. Thanks Phil
Is the coolant fan coming on when the car is getting hot ? Mixing different types of antifreeze and using tap water can block the radiator . Also question the water pump
I have also had owners come to me with this problem and on the odd time it was not any of the above it turned out to be the grills or fogs in the mouth blocking fresh air to the rad???but you must be aware that the stock gauge is an idots gauge once it gets to the centre it will stay there,your oil gauge is the same so keep an eye on your oil do not trust the gauge.
Had exactly the same problems on the way to the Sparkford rally, new radiator from mx5 parts solved this. Genuine mazda and under £100.00. Took about an hour to fit.