Should You Top Up or Replace Insufficient Coolant?
3 Answers
If the coolant level is low but still usable, you can simply top it up with more coolant; if the coolant is no longer usable and the level is low, it needs to be replaced. Most cars use water-cooled engines, which rely on coolant for heat dissipation. In water-cooled engines, the coolant typically follows two circulation paths: a major cycle and a minor cycle. Coolant should be replaced regularly. If not changed for a long time, the coolant's freezing point will rise and boiling point will drop, affecting the engine's normal operation. The full name of coolant is antifreeze coolant, meaning it has antifreeze properties. Antifreeze prevents the coolant from freezing in cold weather, which could otherwise crack the radiator or damage the engine cylinder block.
Last time I had my car serviced, the mechanic said that if the coolant is low, I should just top it up with the same color of original factory fluid. But it's important to note that mixing different brands can cause chemical reactions and clog the pipes. My old car suffered from this last year—after mixing coolants, flaky substances appeared in the radiator. It's best to keep a bottle of original coolant in the trunk for emergencies. During routine checks, if the fluid level is below the minimum mark, top it up. If you need to top it up more than twice a year, there might be a leak, and you should check the radiator or pipes. For cars older than five years, it's advisable to completely replace the coolant, as the old fluid's anti-corrosion agents degrade and can corrode the engine. Once before a long trip, I tested the freezing point and found it had failed—I almost froze the radiator in the north.
Checking the auxiliary tank's level marks is crucial. For minor shortages, simply top up with the same coolant, but refer to the manual to confirm mixing rules. My neighbor's Japanese car had its aluminum water pump impeller corroded after mixing coolants. If the level keeps dropping frequently, it's likely due to hose connection leaks or radiator pinholes. Last time I found pink crystals under my car - telltale signs of coolant leakage. It's recommended to replace coolant every two years; old fluid turns acidic and erodes seals (how repair shops make money). DIY replacement requires proper air bleeding, or vapor lock at high temps will make the temperature gauge spike - don't ask how I know.
