Search Results

This paper summarizes the study of the effects of oil formulation on fuel consumption using Japanese diesel engines and vehicles. Several test techniques are described for screening fuel-efficient diesel engine oils. A diesel engine oil formulated with the optimized combination of detergent-inhibitor package and friction modifier (borate), and multigraded to 10W-30, proved to exhibit the maximum fuel economy and to pass requirements for CD quality. The improvements demonstrated in dynamometer engine tests have been confirmed in extensive field testing.

In Japan, turbocharged passenger cars have recently been introduced with increased improvements in fuel economy and engine performance. However, a turbocharger is driven by hot exhaust gas, so that an engine oil with superior thermal stability is required. After studying a turbocharged engine's thermal effects, two laboratory screening tests that correlate with dynamometer engine tests were established. These tests, termed the panel coking test and the high temperature panel corrosion test, enable one to evaluate base oils, additive components and viscosity index improvers for a given engine oil. Finally, a 10W-30 engine oil formulated by using these tests, showed superior deposit control and anticorrosion performance in the dynamometer engine test and actual driving conditions.

This paper relates the smoke reducing characteristics of two-cycle engine lubricants containing polybutene. Making use of these oils instead of conventional ones, not only smoke but also particulate emissions were reduced, while hydrocarbon concentrations were not affected at all. More than ninety percent of the particulates were unburned lubricant, which account for visible smoke. Diluents such as kerosene and leaner fuel/oil ratios also contributed to the reduction of both smoke and particulates.

This paper describes a study of the effects of oil composition on visible smoke, engine cleanliness, and piston anti-seizure performance. Two laboratory tests, termed the DSC (Differential Scanning Calorimeter) method, and the HTT (Hot Tube Test) are investigated as screening tests for two-cycle engine oils. Two types of oil were developed to comply with stringent Japanese oil requirements. Firstly, smokeless type oils formulated, with high concentrations of polybutenes were introduced to greatly reduce visible smoke from two-cycle engines of high specific output. Secondly, low-friction oils containing ester type synthetic base stocks were developed to achieve higher engine output in racing applications.