What Causes Antifreeze to Enter the Fuel Tank?
2 Answers
Antifreeze entering the fuel tank can occur due to the following reasons: 1. When the cylinder head gasket is damaged, the high-pressure coolant from the water channel may leak into the oil return hole; 2. For engines equipped with an oil cooler, leaks can occur due to quality issues or corrosion of the cooler; 3. Damage to the fuel injector copper sleeve sealing ring can allow antifreeze to enter the fuel tank through the return oil passage. The functions of antifreeze include: 1. Providing anti-corrosion protection for the engine's cooling system; 2. Preventing water from boiling when the engine temperature reaches 100 degrees Celsius; 3. Preventing scale formation, which can reduce the radiator's cooling efficiency; 4. Ensuring the engine operates normally under low-temperature conditions.
I once encountered the issue of coolant leaking into the fuel tank in my old car. While driving, I noticed the engine sounded off and had difficulty starting. When I opened the fuel tank cap, I smelled a strange mixture of sweetness and gasoline. At the repair shop, the mechanic diagnosed it as a damaged cylinder head gasket, which allowed coolant to leak from the cooling system into the engine and then mix with the fuel. This typically happens in aging vehicles or after engine overheating causes seal failure. If left unrepaired, the coolant can dilute the engine oil, leading to insufficient lubrication and severe wear on components like pistons and crankshafts. The repair was quite expensive, involving engine disassembly to replace the gasket, costing me over a thousand dollars. I recommend car owners regularly check the coolant level and color, and address any abnormalities early.
