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A laboratory wear test is used to evaluate the wear protection properties of new and used engine oils formulated for FFV service. Laboratory-blended mixtures of these oils with methanol and water have also been tested. The test consists of a steel ball rotating against three polished cast iron discs. Oil samples are obtained at periodic intervals from a fleet of 3.0L Taurus vehicles operating under controlled go-stop conditions. To account for the effects of fuel dilution, some oils are tested before and after a stripping procedure to eliminate gasoline, methanol and other volatile components. In addition to TAN and TBN measurements, a capillary electrophoresis technique is used to evaluate the formate content in the oils. The results suggest that wear properties of used FFV lubricants change significantly with their degree of usage.

A short engine sequence test, based on the Sequence VD procedure, was used to screen FFV oil candidates more rapidly. Since only one engine is needed to compare the wear-protection performance of several lubricants, engine hardware variability is not a significant issue in this test procedure. Several lubricants, some specially formulated for FFV engines, were tested using standard Sequence VD engine hardware which includes molybdenum top piston-rings. Results showed clear discrimination of the performance of oil candidates. These lubricants were also tested using an engine with chromium-faced top rings and exhibited similar performance ranking.

A pressure transducer, closely mounted to the fuel rail pressure regulator of a production fuel system, captured transient waveforms in a bench experiment. Signals were processed to detect the reduction of fuel flow caused by injector clogging. Interference among wave patterns and the proximate action of the pressure regulator made quantitative correlation difficult. However, changes in wave amplitudes can be qualitative indicators of injector clogging problems. A modification was made that moved the regulator nearer the fuel pump outlet and deadheaded the rail. With these modifications, sequential transient pulses from a single operating injector showed good correlation between the pressure drop in the fuel rail during injection and the injector static fuel flow rate. To apply this behavior to multi-cylinder engine analysis, a waveform superposition method was developed to extract single injector information during multi-injector operation.

The variation of viscosity with temperature and shear rate plays an important role in the analysis of lubrication of automotive systems. In this paper, a method for predicting the viscosity of non-Newtonian fluids, such as multigrade engine oils, over a wide range of temperatures and shear rates is outlined. This expression determines viscosity parameters for shear thinning fluids in terms of easily measured viscosity values at some reference state. A comparison of predictions with experimental data suggests that viscosity for multigrade engine oils can be predicted to within experimental uncertainty. The proposed method can be used in assessing lubricant viscosity at shear rates greater than 106 s-1, which are beyond the capability of current laboratory instruments. A comparative study with multigrade oils shows that performance at very high shear rates cannot be accurately gauged from high temperature, high shear (HTHS) viscosity measurements.

Rheological measurements were performed on a series of lubricants for flexible fuel vehicles, and blends of water or methanol in these oils. A series of measurements, including kinematic viscosity, viscosity at low and high shear rates, low shear viscosity under borderline pumping conditions, and density were performed on all oils and blends. The effects of mixing conditions, such as mixing speed and temperature on these properties were also studied. Viscosity increases when water emulsifies in oils. Methanol exhibits limited solubility in all oils, but more so in synthetic base oils. Viscosity tests at 248 K (-25°C) do not indicate the onset of critical pumping conditions, even at high concentrations of water or methanol. Tests at high shear rates at 323 K (50°C) suggest that water-oil emulsions are quite stable, while methanol-oil blends lose their methanol content either due to evaporation or shear-induced separation.

A single cylinder indirect injection diesel engine was used to evaluate the emissions, fuel consumption, and ignition delay of non-petroleum liquid fuels derived from coal, shale, and tar sands. Correlations were made relating fuel properties with exhaust emissions, fuel consumption, and ignition delay. The results of the correlation study showed that the indicated fuel consumption, ignition delay, and CO emissions significantly correlated with the H/C ratio, specific gravity, heat of combustion, aromatics and saturates content, and cetane number, Multiple fuel properties were necessary to correlate the hydrocarbon emissions. The NOx emissions did not correlate well with any fuel property. Because these fuels from various resources were able to correlate succesfully with many of the fuel properties suggests that the degree of refinement or the chemical composition of the fuel is a better predictor of its performance than its resource.

A 98-hour sequence test has been developed to study the wear of Ford OHC 2.3L methanol fueled engines. This test requires only half the test time of an ASTM Sequence V-D test used by many researchers, and yet provides sufficient severity to generate measurable bore wear to discriminate engine hardware changes. A portable fixture was designed to provide rapid, convenient, and accurate measurement of radial bore wear at a prescribed depth in the cylinder. The fixture can measure radial bore wear with accuracies to 0.004 mm. Its portability allows on-site measurement of engines on dynamometer test stands, or in vehicles with minimal engine disassembly. The test procedure and measurement fixture were used to quantitatively document the ring and bore wear effects of numerous variables, such as fuels, fully formulated lubricants, top ring configurations, coolant temperatures and flow patterns, intake heat addition, and fuel contamination.