Modern marine Diesel engines, with their high operating pressures and temperatures, require, sophisticated crankcase oils, and to keep the performance levels of these oils close to the original levels and avoid operational problems, careful oil-maintenance procedures must be followed. In this paper, various aspects of Mobil's experience and views of the maintenance of modern crankcase oils are described under the headings:--1. Functions and Properties of Crankcase Oils related to Oil Maintenance. 2. Typical Bearing Failures Caused by Abnormally Contaminated Crankcase Oils (1--Bearing Corrosion by Sea Water Contamination. 2--Bearing Corrosion Caused by Acids. 3--Bearing Failure Caused by Solid Contaminants). 3. Crankcase Oil Contamination: Sources--Components--Effects (1--Contamination Sources. 2--Contamination Components and Effects: Combustion Products; Water; Fuel; Miscellaneous Contaminants; Catalytic Effect of Contaminants; Particle Size of Contaminants). 4. Crankcase Oil Treatment (1--Chemical Treatment. 2--Filtration. 3--Centrifuge Oil Treatment. 4--"Aquanul" System for Water Removal). 5. System Oil Volume. In a concluding section of the paper, it is mentioned that, for crankcase oil maintenance, the main builders of large crosshead engines have adopted 50-micron full-flow filters and by-pass centrifuges, with an additional coarse filter on the suction side of the pump. This is close to the optimum system if the centrifuge has adequate capacity, but full-flow filters of a finer size than 50 microns would be preferable. The main builders of medium-speed Diesels have adopted full-flow filters with pore sizes ranging from 10 to 40 microns, and in addition a finer filter and/or a centrifuge is installed in a by-pass. For these engines, the optimum system is considered to be a full-flow filter of 8-10 micron size, with a by-pass centrifuge of adequate capacity. The centrifuge is essential for the removal of water. Order from BSRA as No. 53,479.

  • Supplemental Notes:
    • From the Marine Diesel Engine Technology Symposium, 1978.
  • Corporate Authors:

    Mobil Oil Company Limited

    150 East 42nd Street
    New York, NY  United States  10017
  • Publication Date: 1978

Media Info

  • Pagination: 28 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00317471
  • Record Type: Publication
  • Source Agency: British Ship Research Association
  • Report/Paper Numbers: Conf Paper
  • Files: TRIS
  • Created Date: Oct 8 1980 12:00AM