the coolant goes through the radiator too fast to be cooled sufficiently. a thermostat will help get the engine to operating temp and the let only enough coolant through to keep engine at that temp. this slows coolant down enough to be cooled properly.
Without a temperature guage, the most acurrate way would be to use a infrared temp. gun and aim it at the thermostat housing/radiator/water pump.
Could be a bad water pump.
That depends on the thermostat. If it's a 185 thermostat, the engine should run at 185. If it's running too hot, check the thermostat, radiator and water pump. If it's running too cold, replace the thermostat.
Running your engine without a thermostat will cause it to run hot. An engine will run cooler initially without a thermostat. After that IT WILL NOT! Why you ask? Again, physics. An engine running without the restriction of the thermostat in the system (remember, even when it's wide open there's still some restriction in the system caused by the thermostat's small opening) will not keep the coolant in the radiator long enough for the radiator to 'radiate' the heat. That is, the coolant must stay in the radiator for a certain amount of time to dissipate some of the heat it has absorbed from being in the engine block. The coolant is in the block. It's hot. It moves to the radiator and gets rid of some of the heat. If it moves through the radiator too FAST, without the restriction of the thermostat body, it won't get rid of as much heat. Basic Thermodynamics at play.
First determine if the engine is really running hot if it is check to see if you are low on water, or could be the thermostat is not opening.The thermostat allows water to enter the engine block after it reaches a certain temp.
If it shows hot on the gauge and it is not hot, there is a gauge or sensor problem.
Running a vehicle without a thermostat will cause it to take longer to warm up and your interior heater may not blow hot air.
That means the engine is running HOT for some reason. Check the thermostat, Radiator and coolant level. Repair as needed.
A thermostat can be stuck open or closed. If the engine runs to cool it is stuck open. If the engine is running hot it is stuck closed. If you don't have these problems you should'nt have to change it.
The purpose of the thermostat is to ensure the engine stays in the designated normal operating temperature range ( at or above the temperature rating of the installed thermostat ) . If you remove it , the engine will not reach the proper temperature and the computer will sense the cool running engine and will enrich the fuel mixture to compensate for the situation . In other words ,your engine will always be running rich ( using too much fuel ) which will hurt engine performance and kill your MPG ! This also will cause a failure if your car is subject to smog and emission testing !
Try the thermostat, second see if the heater core is plugged up if that's not the problem see if the engine is even running hot enough
Yes, that is about what it should be with a 195 degree thermostat installed. Check your radiator for debris on the outside or it may be partially clogged.