ASTM D8279-25
Standard Test Method for Determination of Timing-Chain Wear in a Turbocharged, Direct-Injection, Spark-Ignition, Four-Cylinder Engine
| Označení normy: | ASTM D8279-25 |
| Vydáno: | 01.07.2025 |
| Status: | Active |
| Počet stran: | 64 |
| Sekce: | 05.05 |
| Označení: | blowby; chain elongation; chain wear; engine oil; ramp; timing chain; turbocharger; |
| ASTM označení: | ASTM D8279 |
| Nahrazuje: | D8279-24 |
1.1 Undesirable timing-chain wear has been observed with gasoline, turbocharged, direct-injection (GTDI) engines in field service, and data from correlating laboratory engine tests have shown that chain wear can be affected by appropriately formulated engine lubricating. A laboratory engine test has been developed to provide a means for screening lubricating oils for that specific purpose. The laboratory engine test is 216 h in length, conducted under varying conditions, and the increase in timing-chain length determined at the end of test is the primary result. This test method is commonly known as the Sequence X, Chain Wear (CW) Test.
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.
1.2.1 Exception—Where there is no direct SI equivalent such as screw threads, national pipe threads/diameters, tubing size, or specified single source equipment.
1.3 Table of Contents:
|
| Section |
| Scope | 1 |
| Referenced Documents | 2 |
| Terminology | 3 |
| Summary of Test Method | 4 |
| Significance and Use | 5 |
| Apparatus | 6 |
| Test Engine | 6.1 |
| Reagents and Materials | 7 |
| Preparation of Apparatus | 8 |
| Timing-chain Preparation, Installation, and Measurement | 8.20 |
| Test Stand Installation | 8.21 |
| Electronic Throttle Controller | 8.21.17 |
| Temperature Measurement | 8.23 |
| Pressure Measurement | 8.24 |
| Flowrate Measurement | 8.25 |
| Blowby Flowrate | 8.26 |
| Stand Calibration | 9 |
| Test Procedure | 10 |
| Pre-Test Procedure and Engine Break-In | 10.1 |
| Engine Start-up Procedures | 10.2 |
| Test Sequence | 10.3 |
| Engine Shutdown Procedures | 10.4 |
| Blowby Flowrate Measurement | 10.5 |
| Parameter Logging | 10.6 |
| Oil Consumption Calculation | 10.7 |
| General Maintenance | 10.8 |
| Special Maintenance Procedures | 10.9 |
| Blowby Flowrate Adjustment | 10.10 |
| Diagnostic Data Review | 11 |
| Test Results | 12 |
| Report | 13 |
| Precision and Bias | 14 |
| Keywords | 15 |
| ANNEXES |
|
| ASTM TMC Organization | Annex A1 |
| ASTM TMC: Calibration Procedures | Annex A2 |
| ASTM TMC: Maintenance Activities | Annex A3 |
| ASTM TMC: Related Information | Annex A4 |
| Engine and Stand Parts | Annex A5 |
| Safety Precautions | Annex A6 |
| Engine Rebuild Templates | Annex A7 |
| Engine Build Records | Annex A8 |
| Cylinder Head Build | A8.1 |
| Cylinder Bore Measurement | A8.2 |
| Bearing Journal Measurements | A8.3 |
| Engine Part Photographs, Schematics and Figures | Annex A9 |
| Control and Data Acquisition Requirements | Annex A10 |
| Dipstick Oil Level to Charge Conversions | Annex A11 |
| Sequence X Report Forms and Data Acquisition | Annex A12 |
| APPENDIXES |
|
| Sources of Materials and Information | Appendix X1 |
| Suggested Designs for Engine Fixing Brackets | Appendix X2 |
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.