In many cases there is no need for external lubrication, and fuel pumps keep at bay with the aid of only what fuel they deliver to the rest of the system. Modern vehicles commonly use in-tank fuel pumps, which rely on the gasoline purchased to lubricate internal components like her motor and impeller. The smoother operation and much longer lifespan result from lower friction between moving parts as fuel flows through the pump. It is very important that you keep the fuel level above 1/4 tank when using a high performance or inline fuel pump, which keeps them immersed and out of a possible dry start situation that can cause higher than normal heat and wear.
When lubricated, the gearbox and diesel fuel pumps depend primarily on fuel cells for this purpose (Diesel has better natural lubrication due to its higher viscosity). But polluted or poor quality diesel with impurities or water can prevent the lubricating properties, which leads worsening of parts-ceremony. Fuel filters should be changed at regular intervals — usually around every 30,000 miles or so — to ensure the performance of the pump by keeping contaminants away from it.
On older pumps or engines, this added step can be necessary (especially in diesel systems, where the pump components can wear) to address the use of additives for additional lubrication. Lubrication benefits, reduced friction, and ultimately preventing damage are a result of the specialized diesel additives. Diesel Knocking (Source: BP)quality diesel additives can increase the lifespan of a pump by 15%, particularly in older vehicles or pumps working under high-stress conditions.
Although gas is the primary lubricating agent, symptoms of a failing fuel pump – increased noise; rough starts; reduced fuel economy – can also be indicative that it’s not producing enough lube. Remember, the words of automotive expert Carroll Shelby, “The cleaner your machine, the longer it will run,” so with quality fuel and a clean tank (in which sediments could impair pump lubrication), circulation through the in-tank fuel pump is guaranteed. Supplying the Fuel Pump with uninterrupted fuel access also aids in its efficient operation without extra lubrication, promoting stable performance and overall longevity.