Does Gasoline in the Fuel Tank Evaporate?
2 Answers
Gasoline in the fuel tank does evaporate, but the amount of evaporation is minimal. This is because the fuel tank is not a completely sealed device. To prevent fuel splashing during refueling, the tank is equipped with a ventilation pipe connected to a charcoal canister, which in turn has a pipe leading directly to the atmosphere. Methods to prevent gasoline evaporation in the fuel tank include: 1. Lowering the temperature to reduce chemical activity; 2. Applying Vaseline at the contact point between the cap and the tank; 3. Using a tank that is less prone to oxidation. The cleaning method for the fuel tank involves: 1. Cleaning and inspecting the exterior of the tank, checking for dents and leaks in the tank, fuel pipes, and joints; 2. Performing tank cleaning by opening the fuel tank cap, removing the filter screen, and siphoning out part of the fuel, leaving about 30 liters of fuel in the tank.
A few days ago, while getting my car repaired, I heard an interesting tidbit from the experienced mechanic: gasoline in the fuel tank does indeed evaporate quietly! Especially after being exposed to the summer sun, you can hear a hissing sound when opening the fuel tank cap—that's the fuel vapor. But don’t panic, fellow drivers. Our cars are equipped with a charcoal canister system specifically designed to absorb these vapors and prevent pollution. I’ve personally experienced this: an older car that sat for too long had trouble starting, and it turned out the charcoal canister was clogged. If you smell gasoline, notice a sudden increase in fuel consumption, or hear a noticeable suction sound when opening the fuel tank cap, it’s almost certain there’s an issue with the fuel vapor circulation system. In that case, quickly check the charcoal canister and the related lines—after all, no one wants to drive around smelling gasoline, right?
