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Meeting Engine Manufacturer's Cleanliness Requirements

High quality, clean fuel is no longer an option. In the past, diesel engines could tolerate fuel that was dirty or slightly substandard. Not so today. Engine manufacturers require high quality fuel. Cleanliness mandates call for a higher level of filtration than ever before. Currently, the WWFC recommends an ISO cleanliness rating of 18/16/13 with no free or emulsified water (less than 200 ppm). What does this mean?

The International Standards Organization (ISO) identified a solid contamination code standard 4406:1999 for diesel fuel. Currently that standard is 18/16/13. According to ISO code, the amount of solid contamination in fluid is measured in 100 ml samples at specified size ranges. The ranges are 4µm, 6µm and 14µm. If you follow the chart to the right, a 100 ml sample of diesel with a rating of 18/16/13 would have 130,000-250,000 4µm particles, 32,000-64,000 6µm particles and 4,000-8,000 14µm particles.

Research shows that the typical diesel delivery ranges from ISO 22/20/18 to 21/19/17. At this level, the end user can expect to see engine performance problems and maintenance issues. The requirement for modern engine injectors is 11/08/06 due to a nozzle clearance of 2µm. The Tier 4 compliant engine requires ultra clean fuel be used. Tier 5 is expected to be in place by 2019 and discussions of a new ISO requirement of 12/09/06 will likely be necessary. That’s 64 times cleaner than 18/16/13.

High quality filtration is a reality and the need for a fuel quality management program is an absolute must. Additionally, the challenges with managing biodiesel amplify the need. Most tank systems are not designed to maintain Tier 4 or 5 level fuels. Constant particle and microbial contamination as well as water are a continual problem. The large majority of storage tank operators know nothing about fuel quality guidelines and requirements. The chart below offers a real challenge to fuel operators and diesel engine owners. Clean fuel does not just happen!