After a period of time, even if the antifreeze containing the corrosion inhibitor remains in the cooling system of the car throughout the year, the deposits will accumulate.
Eventually the deposit will begin to block the water passages in the radiator and engine. This obstruction causes the engine to overheat, which can cause the engine to get stuck if the engine becomes severe.
If your engine is overheated and you have eliminated other possible causes (such as leaks), the water passage may be blocked or narrowed by deposits. To remove them, flush the radiator and engine thoroughly.
Prior to rinsing, the old coolant is drained from the system and discarded, and sediment deposits can contaminate it. But remember, the antifreeze contained in the coolant is toxic. Prepare a large container to collect it so that it can process toxic waste later in the nearest dump.
With the engine cold, remove the pressure cap from the radiator or expansion tank. Turn the heater control to hot.
If the radiator has a drain plug, remove it; if there is a drain tap, open it - look in your car handbook to see which way it turns, as it can be broken easily.
If no coolant runs out, gently poke the hole clean with a piece of wire, or unscrew the tap completely.
If there is no tap or drain plug, disconnect the bottom hose at the radiator end.
There may also be a drain tap on the engine block. If so, open it.