Outboard & Small Engine Lubricant Evaluations
Office of Automotive Engineering

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Evaluation of lubricants for outboard marine engines are conducted in large water tanks specially designed for this purpose.

Southwest Research Institute (SwRI) evaluates lubricants used in a variety of two- and four-stroke cycle, air- and water-cooled engines used in outboard marine, and small utility engine applications. Over a dozen test methods based on ASTM-TC, National Marine Manufacturers Association (NMMA), International Standards Organization (ISO) and JASO standards are available to evaluate lubricants 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 cycle, water-cooled engines, including the NMMA TC-W3®, FC-W® and FC-W Catalyst Compatible® specification tests. For two-stroke cycle, air-cooled engines, the International Standards Organization (ISO) has adopted worldwide test procedures to evaluate lubricants for exhaust smoke, exhaust system deposits, lubricity, and piston cleanliness. These test methods, conducted by SwRI, supplement the ASTM-TC specification tests.

Test Methods for Marine and Small Air-cooled Engines

Detailed test specifications are available for each of the tests offered below.

Related Terminology

outboard  •  small engine lubricants  •  nmma  •  national marine manufacturers association  •  jaso  •  marine engine  •  outboard marine  •  tc-w3®  •  fc-w®  •  fc-w catalyst compatible®  •  astm-tc  •  two-stroke  •  small utility engine  •  air-cooled engines  •  lubricity  •  lubricants  •  detergency  •  exhaust system blocking  •  lubricant testing  •  combustion chamber deposits  •  deposits  •  exhaust blocking  •  general performance engine test  •  gpet  •  pre-ignition  •  y350m2  •  ce50s  •  m340-92  •  m341-92  •  m342-92  •  m343-92  •  af-27

Benefiting government, industry and the public through innovative science and technology
Southwest Research Institute® (SwRI®), headquartered in San Antonio, Texas, is a multidisciplinary, independent, nonprofit, applied engineering and physical sciences research and development organization with 9 technical divisions.