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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 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.