How to Change the Water in a Car Radiator?
3 Answers
With the car engine cooled down, unscrew the radiator cap, open the radiator drain valve, and drain the antifreeze. Insert a rubber hose connected to a tap water pipe into the radiator filler port, then turn on the tap until clear water flows out from the radiator. After the cooling system is completely drained, close the radiator drain valve. Start the engine and let it idle for 2-3 minutes, then securely fasten the radiator cap.
As a friend who has driven for many years, I've changed the radiator coolant several times myself. The process isn't actually difficult, but requires careful attention. First, wait for the engine to completely cool down—at least a few hours after turning it off. Never risk doing it hot, as steam or scalding liquid could cause injury. Then locate the radiator cap, slowly twist it open to release pressure (wearing gloves is safer). Find the drain valve under the car, unscrew it to let the old antifreeze or water flow into a container. Afterwards, flush the system—I usually connect a hose and rinse for several minutes to ensure residue is removed. After thorough draining, prepare the new mixture—typically 50% antifreeze and 50% distilled water—then pour it directly into the radiator until full. Finally, start the engine to circulate the fluid for a few minutes, expel air bubbles, and check if the fluid level meets requirements. Remember to change it every 20,000-30,000 km or every two years to prevent engine overheating issues. Personal tip: Wear old clothes to avoid staining yourself. The whole process takes about half an hour, saving repair costs while learning new skills.
As a beginner in car maintenance, I decided to DIY my radiator fluid change for cost-saving and safety reasons. Starting with the basics: Park the car on level ground and ensure the engine has cooled for several hours before starting. Wear gloves for hand protection. Slowly loosen the radiator cap to release pressure, listening for a 'hiss' sound. Locate the drain plug underneath the car – usually positioned below the radiator, use a wrench to open it and drain the old fluid into a bucket. After draining, close the plug and flush the interior with water to remove residue. I recommend using bottled water for flushing, 2-3 rounds should suffice. Then pour in the new antifreeze mixture, following the manual's ratio or a 50% antifreeze to 50% distilled water mix, pouring slowly to prevent overflow. Start the engine and let it run for a few minutes, then check and top up the fluid level. Note that newer cars have more sensitive cooling systems, so monitor the temperature gauge post-change. Safety first: Never work on a hot engine, and avoid slips or chemical contact. This is a great opportunity to familiarize yourself with your car's structure and build confidence for other minor maintenance tasks.
