the hoses leading to and from your radiator might be clogged. If you had a rusty radiator, the rust may have clogged the hoses that carry the coolant. you should check all your hoses and even flush them out.
the thermostat will be under the THERMOSTAT HOUSING, which is where the TOP radiator hose fits on ie(radiator to thermostat housing) this keeps the engine at an OPTIMUM temperature BUT can be A cause of OVERHEATING IF malfunctioning
Yes, a thermostat opens and closes in response to the temperature in the cooling system under normal conditions. If it is sticking it can cause fluctuations in the radiator coolant temperature.
bad thermostat or water pump
it is possible that you have a faulty thermostat or you have air pockets in the new radiator when the new coolant was added
No. The thermostat controls the flow of water through the radiator, not the heating core. Using a thermostat with a higher temperature rating delay the opening of the thermostat (and the flow of water to the radiator) until that higher temperature is reached. This will cause the coolant to run hotter.
Most of the time it is because the thermostat has gone bad and is not opening at the proper temperature. Cure: replace thermostat. If the thermostat has been replaced, flush the radiator. Buildup of residue in the bottom of the radiato0r will cause overheating, but it is maintained over heating, not temporary.
Ingeneral, the fan will run only if the temperature of the radiator is above the normal range. If the fan is running, then the radiator must be over temp unless the radiator fan thermostat or it's relay is defective. If the radiator truly is over temp then you have a larger over-heating problem You state the thermostat was replaced. if you replaced the fan thermostat then either the radiator really is over temp and it is doing what it should, or there is a problem with the thermostat-fan relay or switch. If you replaced the engine thermostat that controls the flow of coolent between the engine and the radiator, then that probably wasn't your problem and you should look elsewhere for an overheating cause. I would start by determining if the engine actually is overheating or not. If it is, I would look for coolent system problems like the engine thermostat (if you didn't replace it already), water pump, leaks, scale build up in the radiator, or blockages in the system. If the engine isn't overheating then I would consentrate on the fan, fan thermostat and relays.
clogged radiator, advanced timing, worn water pump, dragging brakes, etc. Usually, the thermostat isn't the real cause of overheating.
If the top hose gets hot that means that the thermostat HAS opened. Thermostats remain closed until the engine warms up then the thermostat only opens enough to keep the temperature at about the set-point temperature of the thermostat. Just repair the radiator and enjoy the vehicle.
This question is not complete. . Need to know if you've replaced radiator, thermostat, hoses etc. Are you asking this question *after* yo checked the thermostat, changed, added or drained the system?
There is an engine temperature sensor that operates the cooling fan.
If there is no thermostat in the radiator, the coolant can flow too quickly through the system and fail to properly regulate the temperature. This can cause the coolant to boil over and be expelled from the radiator. Installing a thermostat can help control the flow of coolant and prevent overheating.