EFFECT OF ENGINE OIL ZINC DITHIOPHOSPHATE (ZDP) ADDITIVE TYPE ON CAM AND LIFTER WEAR IN TAXI SERVICE
The major phosphorus-containing compounds in engine oil are zinc dithiophosphates (ZDP's), which act both as antioxidants and antiwear agents. To reduce engine oil phosphorus concentrations without compromising engine durability, and thereby reduce phosphorus poisoning of emission control devices, an optimum ZDP mixture should be used. A 160,000-km taxi test was conducted to determine the relative camshaft and lifter wear protection provided by several ZDP's and ZDP mixtures. Wear protection was poorest with aryl ZDP's (which are thermally stable, as determined by differential scanning calorimetry (DSC)), intermediate with long-chain primary alkyl ZDP's (which are thermally unstable), and best with short-to-medium chain secondary or short-chain primary alkyl ZDP's (which are of intermediate thermal stability). Sequence IIID test results on analogs of the field test oils correlated fairly well with taxi test results; sequence V-D test results did not correlate as well.
- Find a library where document is available. Order URL: http://worldcat.org/issn/01487191
- Reprinted from SP-558 Lubricant and Additive Effects on Engine Wear. Fuels and Lubricants Meeting San Francisco, California, October 31-November 3, 1983.
Warrendale, PA United States 15096
- Smolenski, D J
- Kabel, R H
- Publication Date: 1983
- Features: Appendices; Figures; References; Tables;
- Pagination: 16 p.
- TRT Terms: Camshafts; Durability tests; Engine oils; Machine valves; Oil additives; Wear
- Old TRIS Terms: Valve train
- Subject Areas: Safety and Human Factors;
- Accession Number: 00387430
- Record Type: Publication
- Source Agency: National Highway Traffic Safety Administration
- Report/Paper Numbers: SAE 831760 Reprint, HS-036 787
- Files: HSL, USDOT
- Created Date: Aug 30 1984 12:00AM