How to Check a Cooling System
- 1). Visually inspect the car's cooling system while the car is running, looking over the radiator for holes in the surface whether large or small and looking the hoses over for holes, cracks or tears. Using a water hose or high pressured air hose, spray the surface of the radiator to remove debris that may be clogging the radiator and to reveal punctures in the radiator. Debris, including leaves, rocks and dirt, can reduce the radiator's capacity to radiate heat away from the vehicle.
- 2). Remove the radiator cap from the radiator and connect a radiator pressure testing kit to the top of the radiator to check the radiator's pressure. When the engine is running, the radiator uses the pressure generated to force the coolant through the cooling system and the engine. The pressure testing kit can also be used to check the radiator cap.
- 3). Squeeze the car's radiator hoses (both upper and lower) after turning off the engine and allowing it to cool. Check the hoses for firmness---a firm hose is typically in good condition, while a soft hose is more than likely damaged. Check the hoses for rips and tears and unscrew the metal rings that hold the hoses in place, checking them for damage.
- 4). Open the radiator while the vehicle is cool and check the level of coolant inside of the radiator. If you add coolant, make certain that it is mixed with the proper amount of water, according to the vehicle manufacturer recommendations. Check the coolant for any particles, which could be signs of internal blockages or rust. When the radiator is full, start the engine and let it warm up to see if any of the coolant leaks, or if the vehicle overheats.
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