I've bled the system and refilled coolant as recommended with a bottle on top of header tank and checked thermostat in boiling water, the engine does not overheat when idling but goes up to red when driving normally so i pull over and let the engine idle and then the gauge drops very quickly back to around 90 degrees

daniel, April 2010

P.S changed the wifes CLIO stat even after boil test (R reg) it was ok,changed it anyway, told by good guy in shop that they now operate on pressure as well as the old melted wax principle,made no odds the head gasket had gone anyway,but your test may not be conclusive.Good luck anyway.

Rich, April 2010

Are you sure it is overheating,if you drop it to idle it should continue to overheat and more,not suddenly cool down(engines don't cool down quickly)have you lost any water!if not then you don't have a leak and the head gasket is ok,the water pump may have gone or the sender is telling you lies,does the fan cut in when it should?Why do you think it is overheating,the gauge says it is and five mins later says it isn,t.You've tackled the problem from the middle not the start,go back to the start.

Rich, April 2010