To a large extent, the longevity of diesel engines is a result of the lubricity of diesel fuel. Prior to the early 1990’s diesel fuel had adequate lubricity to ensure minimal wear on crucial, close-tolerance engine parts. Since about 1993, however, in order to clean up the sulfur and aromatic hydrocarbons in diesel emissions, many of the compounds responsible for diesel’s lubricating properties have been removed.
In March, 2000, Quality Management Systems Manager for Stanadyne Automotive Corporation, (Stanadyne makes diesel injection components for Detroit, International, John Deere, and other domestic companies) Paul Henderson stated the following to the Chairman of the Kansas House Environment Committee:
“There have been numerous examples from the field where lack of lubricity in the fuel has caused premature equipment breakdowns and in some cases, catastrophic failures. This problem will be more dramatic as EPA moves to further reduce the sulfur levels in petrodiesel fuel.” – NBB
Biodiesel has far superior lubricating properties to the diesel fuel that is in use today. Table 2, below, shows how a very small amount (1-2%) of biodiesel blended with conventional diesel fuel #1 and diesel fuel #2, is effective in significantly adding lubrication and reducing wear. The test performed is known as ‘HFRR’ which stands for ‘High Frequency Reciprocating Rig,’ and is the test used by fuel injection equipment manufacturers.
A lower number indicates less damage due to wear.
|HFFR Comparison HFRR Scar (microns)*|
|Percent Biodiesel||Diesel Fuel #2||Diesel Fuel #1|
* Results provided by Stanadyne Automotive Corporation – NBB