Why should the tank never be filled to the brim when refueling?

It is often tempting to want to fill the maximum tank of his vehicle in order to take full advantage of the storage capacity and thus avoid making several stops at the service station. However, this practice is not without consequences and can even cause problems on your car. In this article, we will discover the reasons why you should never fill your tank to the brim.

Expansion of liquids and overflows

When you fill your tank to the brim, there is no space left for expansion of the fuel due to temperature variations. This is because liquids tend to expand when it’s hot and contract when it’s cold. Thus, an overfilled tank can lead to overpressure and cause gasoline or diesel spillageespecially in hot weather.

Why you should never fill the tank to the brim when refueling
The dangers of filling your tank to the brim

Hazards to the evaporative fuel system

Modern cars are equipped with a fuel vapor evaporation system (EVAP) which has the function of recovering the hydrocarbon vapors emitted by the tank and reintroducing them into the fuel supply circuit.

This system makes it possible to reduce polluting emissions and to limit the loss of gasoline due to evaporation. However, when you fill your tank to the brim, fuel vapors can mix with the liquid and saturate the device.

refuel at the gas station

Effects on engine operation

If the EVAP system is invaded by liquid fuel, it can no longer fulfill its role correctly and can cause problems with engine operation. Indeed, too much fuel vapor in the fuel system can cause an air-fuel mixture that is too rich, which leads to poor combustion and reduced engine performance. In the long term, this can even damage the catalyst and other vehicle components.

Repair costs and impact on warranty

Damage caused by an overfilled tank may require expensive repairs, especially if the EVAP system or other parts of the engine are affected. In addition, this practice is often considered improper use of the vehicle and can therefore void the manufacturer’s warranty In case of problem. It is therefore preferable to respect the maximum capacity indicated for your tank in order to avoid such inconveniences.

How do you avoid overfilling your tank?

To avoid filling your tank to the brim, just follow a few simple tips:

Gas up
Filling up with fuel the right way
  • Respect the maximum capacity indicated : each vehicle has a specific tank capacity and it is important not to exceed this limit. You can easily find this information in your car’s user manual or on specialized sites.
  • Let the pump stop automatically : When refueling, the pumps are designed to stop automatically once the tank is almost full. Don’t force the gun to add a few extra gallons, it won’t save you a lot of money and could damage your vehicle.
  • Avoid shaking the vehicle : Some motorists believe that by shaking their car, they can get more fuel into the tank. This practice is not recommended, as it can cause overflow and problems with the EVAP system.

A good gesture for the environment and your wallet

Finally, not filling your tank to the brim is also beneficial for the environment and your budget. Indeed, a fuel overflow leads to the emission of polluting gases and the loss of precious distillates. On the other hand, engine running problems and expensive repairs can strain your wallet.

Thus, to preserve your vehicle, the environment and your budget, you should respect the maximum capacity of your tank and not try to fill it to the last drop of petrol or diesel.

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About the author, Kate Williams
I always dreamed of becoming a journalist but life wanted it otherwise. As soon as I have some time to myself, I share here my discoveries and information that I find interesting.
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