Having cooling system problems

[beege88]

I have replaced the radiator, and the water pump and timing belt are only 2 yrs old. The fluid seems to boil out of the overflow before sensor picks up on it. Sensor checked out ok as well as the fans and relays. Any ideas on what to try now? Water pump again? Head gasket?

[cajunwolfman]

Have you tried changing to a higher temp. rated thermostat to alow the coolant to cool down before returning to the engine?