Hello friend, in most vehicles when the thermostat took the engine from the engine, it passes directly to the radiator and thus cools faster, imagine that the thermostat is like a key for the water and that it opens when it is hot letting the water pass through it and the saw when the temperature low From the water they come together where the thermostat is and when it opens to the one at the same time it closes for another redirecting the direction of water fluid, when removing it not all the water passes to the radiator, only part of it and it passes the same inside the engine remaining one sector inside it where the water is still and does not circulate, the engine it cool as effect of siphon the hot water rises more than the cold water but it is not recommended but it is not recommended but it is not recommended but it is not recommended