By June 2006 the US EPA is mandating that at least 80% of the diesel fuel produced must contain no more than 15 PPM of sulfur in road diesel fuel. Quoting from Transport Topics "Current EPA regulations allow for 500 PPM of sulfur. " Prior to 1993 sulfur content was not regulated and sulfur averaged 3,000 PPM.
Why is this important? In 1993 there was a rash of fuel pump failures in older commercial diesel trucks after low sulfur fuel was introduced. Mostly older pumps were affected which had rubber O ring seals that needed the sulfur to maintain thier integrity. Also, sulfur acts as a lubricant in diesel fuel helping to protect parts of the fuel system in direct contact with the fuel.
Sweden intoduced VLSF (very low sulfur fuel) in about 1995. A rash of fuel pump failures caused Bosch to investigate. What they found was that the fuel pump impellors were experiencing rapid wear due to the lack of sulfur's lubricating properties. In part the problem was solved through pump reengineering, and fuel reformulation.
What does this mean for us? While Cummins and others have been working to prepare thier future engines for VLSF, many of our older engines' fuel systems may suffer premature failure. While we hope that refiners will add lubricity enhancers to help prevent these problems, some engines may still be affected.
It may be a wise protective measure during the early stages of VLSF to add fuel additives containing lubricity additives until the full scope of the problem is seen. Hopefully it will not be wide spread, but treating fuel in the short term (perhaps a year) could be cheap insurance against pump failure.
Why is this important? In 1993 there was a rash of fuel pump failures in older commercial diesel trucks after low sulfur fuel was introduced. Mostly older pumps were affected which had rubber O ring seals that needed the sulfur to maintain thier integrity. Also, sulfur acts as a lubricant in diesel fuel helping to protect parts of the fuel system in direct contact with the fuel.
Sweden intoduced VLSF (very low sulfur fuel) in about 1995. A rash of fuel pump failures caused Bosch to investigate. What they found was that the fuel pump impellors were experiencing rapid wear due to the lack of sulfur's lubricating properties. In part the problem was solved through pump reengineering, and fuel reformulation.
What does this mean for us? While Cummins and others have been working to prepare thier future engines for VLSF, many of our older engines' fuel systems may suffer premature failure. While we hope that refiners will add lubricity enhancers to help prevent these problems, some engines may still be affected.
It may be a wise protective measure during the early stages of VLSF to add fuel additives containing lubricity additives until the full scope of the problem is seen. Hopefully it will not be wide spread, but treating fuel in the short term (perhaps a year) could be cheap insurance against pump failure.
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