Specialized Lubricant Evaluations
Concern over energy conservation and environmental pollution has led to leaner oil-to-fuel ratios, which, in turn, have affected lubricant requirements. Exhaust emission reduction could contribute to the two-stroke cycle engine's viability in the near future. The two-stroke cycle engine provides better power-to-weight ratio, higher specific power output, and less frictional loss than the four-stroke engine.
A. Buscher, Manager
Tony Hendrix, Research Technologist
Specialized Lubricant Evaluations Technical Strengths
Southwest Research Institute (SwRI) evaluates lubricants used in two-stroke cycle, air-cooled engines using the ASTM-TC test sequence and JASO standards, which evaluates the lubricant's ability to:
- Resist combustion chamber deposit-induced pre-ignition
- Prevent ring sticking
- Inhibit deposit formation
- Reduce scuffing
- Resist spark plug fouling
- Reduce exhaust smoke
SwRI also offers all engine and chemical tests required to evaluate lubricants for two-stroke, water-cooled engines, including the National Marine Manufacturers Association TC-W3TM specification tests. These requirements have led to improved lubricants that exhibit higher levels of resistance to ring sticking and loss of cylinder compression. In the future, biodegradability of lubricants may become a significant factor for lubricants formulated for the boating industry.
For two-stroke, air-cooled engines, the International Standards Organization (ISO) has recently adopted worldwide test procedures to evaluate lubricants for exhaust smoke, exhaust system deposits, lubricity, and piston cleanliness. These test methods, conducted by SwRI, have supplemented the ASTM-TC specification tests previously used by industry.
With trained personnel and modern laboratory facilities, SwRI helps the petroleum industry monitor future trends and develop lubricants that meet current requirements. In addition, SwRI engineering and technical staff members are available to develop and operate special two-stroke cycle laboratory tests or to design and coordinate custom field tests to meet unique requirements.