What Causes Rapid Loss of Car Coolant?
2 Answers
The main reasons for rapid consumption of engine coolant are: 1. Poor cooling system design. 2. Inefficient circulation leading to fast consumption; When adding coolant, it should be done after the engine temperature has cooled down. During the process, start the engine and gently press the accelerator to expel air from the system. Add the coolant slowly to ensure proper filling. If necessary, follow the manual's instructions to bleed the cooling system. 3. Leakage; Usually, traces can be seen at the leakage points. 4. Coolant entering the cylinder and being burned or entering the oil pan. In mild cases, there will be no water in the oil pan, while in more severe cases, water will be present, and the engine will run unsteadily. Do not immediately assume the issue is with the cylinder head gasket—a damaged intake manifold gasket can also cause coolant to enter the cylinder, as some engines have coolant passages in the intake manifold. If the coolant is being burned significantly, the engine exhaust pipe will emit water and white smoke.
Last time I encountered a rapid loss of coolant, it turned out the radiator was leaking. During a summer road trip, I noticed the dashboard water temperature warning light came on, and upon checking, the overflow tank was almost empty. Later, the mechanic used a pressure tester and found a pinhole-sized crack at the bottom right corner of the radiator—that's where the coolant was slowly seeping out. Actually, aging hose connections or worn water pump seals can also cause leaks. Special reminder: check the heater core, as leaks inside the dashboard are hard to spot—you might only smell a sweet, syrupy odor. Another possibility is a blown head gasket, where coolant mixes with engine oil, leaving a milky white foam on the oil cap. I remember my old car once needed an engine overhaul because of this. If no obvious leaks are visible, there might be an airlock in the cooling system, requiring professional bleeding.
