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Field Trial to Investigate the Effect of Fuel Composition and Fuel-Lubricant Interaction on Sludge Formation in Gasoline Engines
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Abstract
Engine Sludge has reappeared in the last decade as a source of operation problems and in manufacturers warranty claims in Europe and the USA, due to engine malfunction and in some cases engine failure through oil starvation. This sludge has become known as ‘Black sludge’ or ‘Hot sludge’ in Europe. As a result of the problem, bench engine tests have been developed in Europe (CEC-L-41-T-88), and the USA (ASTM Sequence VE). Both these tests have been shown to be particularly sensitive to changes in the fuel composition, even between batches of the same gasoline.
A field trial has been conducted by Shell Research Ltd at Thornton Research Centre, to study the effect of fuel composition and fuel-lubricant interactions on the propensity to form sludge, using a mileage accumulation cycle designed to be severe with respect to sludge formation.
Fuel compositions were taken at the extremes of levels currently found commercially, and the effect of a gasoline detergent additive was also included in the study. Oils with performance meeting API SF and API SG levels were used. The test was designed using a statistical half replicate approach with sixteen vehicles. Four additional vehicles were included to provide a reference to the Sequence VE test.
The results show clear fuel and fuel-lubricant interaction effects on sludge formation and piston cleanliness. The controlling fuel parameters were found to be different for sludge formation in the rocker cover and sump areas. The use of a fuel detergent additive has been seen to have a beneficial effect on sludge control in these vehicles.
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Citation
Galliard, I. and Lillywhite, J., "Field Trial to Investigate the Effect of Fuel Composition and Fuel-Lubricant Interaction on Sludge Formation in Gasoline Engines," SAE Technical Paper 922218, 1992, https://doi.org/10.4271/922218.Also In
References
- Jaynes S.E. Salomon M.F. et.al “Investigations of Lubrication Sludge Formation in the Field: Development of an Effective New Fleet Test Technique” SAE Paper 910748 1991
- Erdman T.R. “The Fate of Ashless Dispersants in Gasoline Engines as Followed by Carbon-14 Radiolabeling” SAE Paper 810015 1981
- Hanson J.B. Harris S.W. West C.T. “Factors Influencing Lubricant Performance in the Sequence VE Test” SAE Paper 881581 1988
- Lillywhite J.R.F. Sant P. Saville S.B. “Investigation of Sludge Formation in Gasoline Engines” CEC Symposium Paris 1989
- Kawamura M. et.al. “Sludge Formation and Engine Oil Dispersancy Evaluation with a Laboratory Scale Sludge Simulator” SAE Paper 892105 1989
- Dimitroff E. Moffitt J.V. Quillian R.D. Jr. “Why, What and How: Engine Varnish” Journal of Lubrication Technology July 1969
- Moritani H. et.al. “Effects of Fuel Composition on Sludge Formation” JSAE Review 12 3 July 1991
- Murakami Y. Aihara H. “Effects of NOx and Unburned Gasoline on Low Temperature Sludge Formation in Engine Oil” SAE Paper 910747 1991
- Associated Octel Company ltd. “European Gasoline Survey 1990” April 1991