A Fuel Pump fails most times when the tank is low because the pump draws on fuel for cooling and lubrication. When fuel levels fall below 25%, the pump motor is then exposed to air, which makes it more prone to overheating and mechanical wear. Under such conditions, its lifespan is greatly shortened, reducing its efficiency and leading to failure.
Heat is one of the leading causes of pump failure in low-fuel situations. When there isn’t enough fuel to fully cover the pump, the motor runs at an extremely high temperature. Some sources show that continued running with low fuel can cut a pump’s life span by as much as 40%, because the absence of cooling accelerates internal wear. All very important seals, impellers, and electrical connections deteriorate after a long time of being subjected to high temperatures.
Sediment in the fuel tank is another common cause of the pump’s failure. After some time, dirt and debris tend to build up at the bottom of a tank. Running the tank low makes this sediment more likely to get sucked into the pump and hence clog the internal components and fuel filter. Mechanics say that 15-20% of failures actually occur because of debris-related damage, and that is why regular replacement of fuel filters is called for every 15,000 to 30,000 miles.
Another problem associated with an insufficient fuel level is the entry of air into the pump. Pumps that are designed for continuous fuel flow-the usual type-operate badly if air pockets disrupt that flow, causing cavitation. This condition destroys the motor and impellers of the pump, severely depressing efficiency and pressure output. The reason can be verified with a fuel pressure test, and readings below the typical 40-60 psi would signal pump malfunction.
Real-world examples show the risks of driving on an almost-empty tank. During one heatwave in Texas in 2021, mechanics witnessed a 30% increase in fuel pump failures due to low fuel. Some of these drivers described issues with stalling and loss of power that were directly related to overheating and contamination in their fuel systems.
Replacement with a good quality pump, such as Kemso Fuel Pumps, avoids these issues. These pumps are engineered to last, designed to operate under strenuous conditions, and optimized to maintain performance even in the most challenging scenarios.
For further information and quality replacement, refer to Fuel Pump. Keeping the tank adequately full and performing periodic maintenance will keep the pump operating efficiently and well away from premature failure.