BETTER PREDICTION OF ENGINE OIL PUMPABILITY THROUGH A MORE EFFECTIVE MRV COOLING CYCLE

The Mini-Rotary Viscometer (MRV), adopted by SAE in 1980 to predict engine oil pumpability, was unable to fail certain commercial oils that caused engine problems in the winter of 1980-81. The latter oils did fail in the seven-day Federal Stable Pour, Cycle C, Test (FSPCCT). A special study of the FSPCCT temperature cycle in the MRV highlighted the importance of a slow cooldown rate in the temperature range of engine oil cloud points. Using this principle, a modified one-day MRV test was developed that fails 1980-81 problem oils. Further modification, however, was required to detect a newly discovered problem oil, PRO-29. Failure-prone oils discovered since 1980 are very sensitive to subtle changes in cooling rate and temperature regime. As the industry proceeds to develop a more effective MRV test, a better insight into the pumpability problems of 1980-81 has been gained.

  • Availability:
  • Supplemental Notes:
    • Fuels and Lubricants Meeting San Francisco, California, October 31-November 3, 1983.
  • Corporate Authors:

    Society of Automotive Engineers (SAE)

    400 Commonwealth Drive
    Warrendale, PA  United States  15096
  • Authors:
    • Smith Jr, M F
  • Publication Date: 1983

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 16 p.
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00390908
  • Record Type: Publication
  • Source Agency: National Highway Traffic Safety Administration
  • Report/Paper Numbers: SAE 831714, HS-036 830
  • Files: HSL, USDOT
  • Created Date: Nov 30 1984 12:00AM