Fuel pumps also have a bad reputation as being brittle, because they need precision and materials that fold over on themselves at a few hundred horsepower. With parts such as carbon brushes, rubber seals, and metal gears made to high standards of performance and weight, the fuel pumps are constructed to deliver or inject fuel at the right volume and pressure. But these materials are sensitive to conditions outside of the optimal range, so the pumps can be easily damaged. There are studies that show that [fuel pumps got up to 30 percent shorter life in pumps exposed to contaminants] since even small debris can wear out fragile internal parts over time.
Heat is another form of abuse that weakens the fuel pump. Because fuel pumps work under high pressure they develop heat and, if not cooled accordingly, they will lose some of their efficiency. Most in-tank fuel pumps depend on the surrounding fuel to cool themselves and avoid overheating. Keeping fuel levels low removes this buffer creating higher temperatures at which the pump must operate. Industry professionals state that operating a gas tank with less than a quarter of a tank can shorten a pump's life by as much as 40 percent, as it runs hotter and experiences more wear on its internals.
Voltage swings are also a recession on diesel pumps. Pumps are generally made to work within a range of voltages — design voltage for an average automobile 12 volts. Most of the voltage drops or spikes are caused by weak battery or bad alternator, and cause the pump to either underperform or overheat. High-performance applications where a 5% drop in voltage may translate into a 15% loss in fuel flow rate, impacting the pump and engine with fuel starvation and subsequent high pump stress.
The stress placed on fuel pumps is exacerbated by the environmental temperature extremes. Fuel thickens in colder temperatures, forcing the pump to work harder to maintain flow rate, while in hotter climates, additional thermal/environmental stress can wear seals out faster. According to automotive companies like Bosch, a common reason pumps do not last as long in extreme climates is because the operational life of their pumps is as much as 20% shorter in such environments.
Rounding out pump fragility is contaminated fuel. Dirt or metal particles can enter the fuel system, contaminating the delivery mechanism of the pump and ruining those precision components. Some of this risk is managed by fuel filters, but naturally, contaminants can ruin pump efficiency over time and contribute to premature wear. Therefore, specialists suggest that filter changes be made regularly to minimize risk of contamination. Not changing filters, however, can shorten a pump life by as much as 25%.
Using a proper Fuel Pump according to your vehicle and avoiding running a low tank can reduce some of the delicacy. These factors include regular maintenance, stable voltage, and clean fuel that will help the pump work optimally, in turn supporting engine performance and service life.