Fuel as Lubricant - Fuel serves a dual function in the ability to copy fuel over parts, combining two steps into one. Gasoline or diesel fuels are pulled through the pump at flow rates of 30-120 liters per hour (LPH), providing necessary lubrication and cooling for internal components - rotors, gears, bushings. By allowing fuel to flow directly from the tank and using it as a means of lubrication, this greatly reduces friction for better efficiency while still remaining resilient at high pressure levels (as much as 60 PSI or even up towards 2000 on direct-injection setups).
Because diesel is basically a lubricant, the pump has an average service life of 7-10 years under ideal circumstances. This service life can be shortened if the flow of particles generated while fuel is burned are not effectively captured, tearing at different parts of your pump. To remove impurities, conventional wisdom amongst the likes of Delphi and Bosch is to swap out your fuel filter every 20K miles or at whatever frequency they suggest, which also cuts pump wear by about a third providing riper lube. Because these fuels often include cleaning agents, they will also help break down deposits and further improve lubrication flow.
For high-performance engines (engines that are working hard) proper lubrication is really critical because running under stress means your Ford 390 engine produces more heat and load. Fuels from other racing applications, like NASCAR or similar high performance sports require fuel pumps which feature materials that are able to withstand very high heat and friction. High-tech ceramic ball bearings are occasionally implemented to improve durability, however these can reduce friction by up 40 percent versus conventional metallic designs allowing fuel pumps smooth operation in extreme temperatures without added lubricants.
Diesel engines, which run much higher compression ratios than gassers and thus will often depend heavily on the inherent lubricity of diesel in order to preserve fuel pump parts. As diesel has a higher viscosity than gasoline, it can be used to lubricate high-pressure fuel pumps in trucks and industrial or agricultural machines. If not properly lubricated, these pumps will fail prematurely, resulting in significant replacement costs ($500 to $1000 for some engines).
As Henry Ford said, Quality means doing it right when no one is looking; a thought that comes to life in the fuel pump with engineering precision where every part has been developed for minimal friction. Manufacturers do this by adding an internal oiling system that allows the pump to be maintained on fuel only, further protecting against unlined fittings and dry jams all while ensuring a longer service life of their parts with less maintenance.
Visit Fuel Pump — To understand engineering of Fuel Pump and explore the best pump alternatives which makes fuel useful for both lubrication, as well as production.