Значение и использование

This test method is used to evaluate an automotive engine oil's control of engine deposits under operating conditions deliberately selected to accelerate deposit formation. This test method was correlated with field service data, determined from side-by-side comparisons of two or more oils in police, taxi fleets, and delivery van services. The same field service oils were then used in developing the operating conditions of this test procedure.

This test method, along with other test methods, defines the minimum performance level of the API Category SL (detailed information about this category is included in Specification D 4485). This test method is also incorporated in automobile manufacturers' factory-fill specifications.

The basic engine used in this test method is representative of many that are in modern automobiles. This factor, along with the accelerated operating conditions, should be considered when interpreting test results.

FIG. 1 Schematic of Engine Fuel System

Область применения

1.1 This test method covers and is commonly referred to as the Sequence VG test, and it has been correlated with vehicles used in stop-and-go service prior to 1996, particularly with regard to sludge and varnish formation. It is one of the test methods required to evaluate oils intended to satisfy the API SL performance category.

1.2 The values stated in SI units are to be regarded as the standard. The values in parentheses are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific hazard statements are given in 7.7, 7.10.2.2, 8.3.4.2, 8.4.4.3, 9.2.6, 9.3.4.5, 12.1.1.7, 12.2.1.4, and Annex A1.

1.4 A Table of Contents follows:

Section Scope1 Referenced Documents2 Terminology3 Summary of Test Method4 Significance and Use5 Apparatus (General Description)6 Apparatus (The Test Engine)7 Sequence VG Test Engine7.1 Required New Engine Parts7.2 Reusable Engine Parts7.3 Specially Fabricated Engine Parts7.4 Special Engine Measurement and Assembly   Equipment7.5 Miscellaneous Engine Components-Preparation7.6 Solvents and Cleaners Required7.7 Assembling the Test Engine-Preparations7.8 Assembling the Test Engine-Installations7.9 Engine Installation on the Test Stand7.10 Engine Fluids (Supply/Discharge Systems)8 Intake Air8.1 Fuel and Fuel   System8.2 Engine Oil and Engine Oil   System8.3 Coolants8.4 Measurement Instrumentation9 Temperatures9.1 Pressures9.2 Flow Rates9.3 Fuel   Consumption9.4 Speed and Load9.5 Exhaust Gas9.6 Humidity9.7 Miscellaneous Laboratory Equipment10 Test Stand Calibration11 Test Procedure12 Pre-Test Procedure12.1 Engine Operating Procedure12.2 Periodic Measurements and Functions12.3 Special Maintenance Procedures12.4 Diagnostic Data Review12.5 End of Test Procedure12.6 Interpretation of Test Results13 Parts Rating Area-Environment13.1 Sludge Ratings13.2 Varnish Ratings13.3 Clogging13.4 Sticking13.5 Used Oil Analyses13.6 Assessment of Test Validity14 General14.1 Used Oil Analyses-Interpretation14.2 Blowby Flow Rate14.3 Manifold Absolute Pressure14.4 Fuel   Consumption Rate14.5 Oil Consumption14.6 Engine Parts Replacement14.7 Quality Index and Deviation Percentage14.8 Final Test Report15 Report Forms15.1 Precision and Bias17 Keywords18 ANNEXES Safety HazardsAnnex A1 Control and Data Acquisition RequirementsAnnex A2 Detailed Specifications and Photographs of ApparatusAnnex A3 Special Service Tools for the Test EngineAnnex A4 Test Engine Part Number ListingAnnex A5 External Oil Heat Exchanger Cleaning TechniqueAnnex A6 Sequence VG Report Forms and Data DictionaryAnnex A7 Dipstick CalibrationAnnex A8 Critical Part Supplier ListAnnex A9 Operational Data Log-Engine OilAnnex A10 Rating WorksheetsAnnex A11 Fuel   Injector Flow MeasurementsAnnex A12 APPENDIXES Piston and Ring Measurements Record FormsAppendix X1 Sources of Materials and InformationAppendix X2 Description of Scott Quarterly Gas Audit ServiceAppendix X3