when fuels act as lubricants
Fuel lubricity has always been an important part of diesel engine operation and more so now with the extremely tight operating tolerances of today ’ s diesel engine fuel pumps and injectors . A fuel with good lubricity provides protection to the fuel system by extending pump and injector life , reducing repair costs , and reducing downtime for the user . Lubricity enhancers are attracted to metal surfaces , causing the additive to form a thin surface film . The film acts as a boundary layer , preventing two metal surfaces from coming into contact . By coating the moving parts , lubricity enhancers reduce wear and help eliminate excessive heat .
Some fuel pump systems are more susceptible to damage from low lubricity fuel than others . As an example , a rotary type fuel pump looks to the fuel alone for lubricity protection , where some pumps also use a lubricating oil for a portion of the lubricity protection . This is not to say that one pump design is better than another , but to point out that lubricity properties are very important to engine performance and even more so in certain types of fuel pumps .
Load
In systems with close tolerances , anything that reduces the lubricating properties of the fuel can cause damage . Water in the fuel , alcohol from some fuel additives , # 1 diesel fuel , or gasoline mistakenly added to the tank can all cause decreases in a fuel ’ s lubricity , which can potentially result in damage . Using fuels with poor lubricity can increase fuel pump and injector wear and , in extreme cases , cause catastrophic failure .
Historically , the sulfur in diesel fuel acted as a natural lubricating agent . Now that sulfur levels must be no greater than 15 ppm , the lubricity properties of the fuel have diminished . Additives have had to make up much of the difference . Dieselex Gold has contained lubricity enhancers ( friction modifiers ) since the early 1950s . The performance benefits recognized for nearly 70 years are even more important today .
Strong lubrication properties extend pump and injector life , reduce repair costs , and ultimately reduce downtime for the user . In performance testing , Dieselex Gold has consistently outperformed the Engine Manufacturers Association ’ s recommended lubricity requirements . You can rest easy that Dieselex Gold provides the protection you need for your diesel engines .
Ball
Cylinder
Fuel on Test B . O . C . L . E .
Motion
The “ Scuffing Load Ball-on-Cylinder Lubricity Evaluator ” ( BOCLE ) test uses a ball pressed against a rotating cylinder , partly immersed in the test fuel , which continuously transfers a thin film of the fuel to the ball / cylinder interface . Fuel lubricity is measured by determining the maximum load ( measured in grams ) that can be applied without causing scuffing . The High Frequency Reciprocating Rig ( HFRR ) test is also used to measure fuel lubricity .