Keywords : lubricants consumption
DIYALA JOURNAL OF ENGINEERING SCIENCES,
2012, Volume 5, Issue 1, Pages 205-220
ABSTRACT: This paper presents the evaluation of Poly(Methyl Methacrylate) or PMMA additive used in Iraqi lubricating oils to improve the characteristics of gasoline engine lubricants. Primarily, the viscosity with viscosity index improvement, represent the indicators
for the evaluation of this type of additives under the influence of engine temperature. The lubricants used in this work, after manual addition of PMMA, were prepared by mixing the Iraqi base oils of grades 150H & 60H (equal amounts of each type) with percentages 100%, 90%, 80%, and 75%, respectively. These prepared mixtures of lubricating
oils – additives were operated 4 hrs in engine of type "air cooled, 4-stroke, single cylinder, gasoline engine 3kw". The tests, were conducted for lubricant temperature during engine running, oil viscosity, viscosity index, and weight of debris (not analytic), on each sample of prepared lubricants.
The results confirmed that the most suitable lubricating oil for gasoline engine; either in summer or winter; was the mixture of 25% PMMA with 75% mixed base oil, with difference percentage not exceeds more than 6% between these two seasons, since it has lower increment of viscosity and lower VI decrease, with the presence of low amount of the
debris (weight percent). This debris can indicate damages to the engine components, for long time engine operation. Finally, the benefits involved that the PMMA was low affected with the increase of engine temperature, according to its bounded properties.
Keywords: PMMA, Poly(Methyl Methacrylate), gasoline engine, engine temperature, oil mixtures-additives, lubricants consumption.