you might want to check for a blown head gasket or a cracked head or block. espically if it loosing water out of the radiator with out leaking on the ground.
Be care-full my radiator blew up and burnt me. I replaced Radiator, thermostat, and water pump. Timing belt is in the way so I replaced it too. OK Now
check your radiator. is it clean or does it need to be replaced? a simple cleaning cured my problem.
did you check the radiator or the head gasket?
check your fan clutch if its weak it will overheat
theyre maybe an air bubble in the block causing it to overheat,or it could also be a bad water pump
dose the electric fan run if not check the relay if it runs check the water pump
Check the timing.
Try taking the thermostat out completely, then see if it still overheats. If so, your only other problem has to be a bubble in the system and it needs to be burped. Took me about an hour to get a stubborn air bubble out!
You either have a cracked block, blown head gasket, or intake manifold gasket leaking coolant into the engine oil. You have bad problems.
Blown head gastet, radiator leaking, thermostat needs to be replaced Blown head gastet, radiator leaking, thermostat needs to be replaced
have the engine timing checked. if the timing is wrong the engine will overheat, are you loosing coolant?is the fan working, is the water pump working?
Here are a couple possibilities. Thermostat in backwards(spring goes toward engine),plugged radiator,radiator hose collapsing, bad head gasket. Hope this helps