ASTM D6593 test method for evaluation of automotive engine oils
ASTM D6593 standard test method for Evaluation of Automotive Engine Oils for Inhibition of Deposit Formation in a Spark-Ignition Internal Combustion Engine Fueled with Gasoline and Operated Under Low-Temperature, Light-Duty Conditions
10. Miscellaneous Laboratory Equipment
10.1 STAR Tester - A STAR (self test automatic readout) tester will be necessary to diagnose the EEC system in case of a malfunction or operational abnormality. Instructions on the use of the STAR tester can be found in the service manual.
10.2 Beaker - A 5000 mL beaker is suitable for the initial oil fill. A 500 mL beaker is suitable for oil additions.
11. Test Stand Calibration
11.1 Verification:
11.1.1 Verify the calibration of test stands with reference oils supplied by the TMC. Stand calibration tests are normally conducted upon expiration of the 180-day calibration time period or 15 non-reference oil tests, or both. However, calibration time periods may be adjusted by the TMC. Any non-reference oil test started within 171 days of the completion date of the previous calibration test is considered within the calibration period, providing not more than 14 non-reference oil tests have been completed since the previous calibration test.
11.1.2 A 22.4-L (3.0-gal) sample of reference oil is provided by the TMC for each stand calibration test.
11.2 Unacceptable Calibration Results:
11.2.1 It is recognized that a certain percentage of calibration tests will fall outside the acceptance limits because of the application of statistics in the development of the acceptance limits. Failure of a reference oil test to meet Shewhart or EWMA precision control chart limits can be indicative of a false alarm or a stand, laboratory, or industry problem. When this occurs, the laboratory, in conjunction with the TMC shall attempt to determine the problem source. The TMC may solicit input from industry expertise (other testing laboratories, the test sponsor, ASTM Technical Guidance Committee, Sequence VG Surveillance Panel, Sequence VG Operation and Hardware Subpanel, and so on) to help determine the cause and extent of a problem. Industry problems shall be adjudicated by the Sequence VG Surveillance Panel.
11.2.2 If the TMC determines the problem is a false alarm and is stand-related, there is no impact on other non-reference tests running in other stands within the laboratory. If the TMC determines the problem is laboratory-related, non-reference tests run during the problem period shall be considered invalid, unless there is specific evidence to the contrary for each individual test.
11.2.3 The TMC will reschedule a calibration test once it is satisfied that no particular problem exists or the problem has been resolved. The laboratory shall provide adequate documentation to support conclusions reached during this process. Attach this documentation to the acceptable calibration test report. It shall provide sufficient information to show how the problem related to other tests operated during the same period.
11.3 Test Stand Modifications - Report modification of test stand control systems or completion of any nonstandard test on a calibrated stand to the TMC immediately. A nonstandard test includes any test completed under a modified procedure requiring hardware or controller modifications to the test stand. The TMC will determine whether another calibration test is necessary after the modifications have been completed.
11.4 Reference Oil Accountability:
11.4.1 Laboratories conducting calibration tests are required to provide a full accounting of the identification and quantities of all reference oils used.
11.4.2 With the exception of new oil analysis required in 13.6, perform no physical or chemical analysis of new reference oils without the permission of the TMC. Retain engine parts from reference oil tests for six months.
11.5 Test Numbering System:
11.5.1 Acceptable Tests - The test number shall follow the format AAA-BB-CCC. AAA represents the test stand number. BB represents the number of tests since last reference. CCC represents the total number of tests on the stand. As an example, 6-10-175 represents the 175 test on Stand 6 and the tenth test since the last reference. Consecutively number all tests on a given stand.
11.5.2 Unacceptable or Aborted Tests - If a calibration test is aborted or the results are outside the acceptance limits, the CCC portion of the test number for subsequent calibration test(s) shall include a letter suffix. Begin the suffix with the letter A and continue alphabetically until a calibration test is completed within the acceptance limits. For example, if three consecutive unacceptable calibration test are completed on the same test stand, and the test stand number of the first test is 6-0-175, the next two test numbers would be 6-0-175A and 6-0-175B. If the results of the next calibration test are acceptable, the test number 6-0-175C would permanently identify the test and appear on future correspondence. The completion of any amount of operational time on tests other than calibration tests will cause the test number to increase by one. Add no letter suffix to the test number of tests other than calibration tests.
